Bio/Biochem Flashcards
(500 cards)
1
Q
im·mu·no·as·say
A
a procedure for detecting or measuring specific proteins or other substances through their properties as antigens or antibodies
2
Q
immunoassay
A
An immunoassay is a biochemical test that measures the presence or concentration of a macromolecule or a small molecule in a solution through the use of an antibody (usually) or an antigen (sometimes)
3
Q
what is ELISA?
A
enzyme-linked immunosorbent assay, an immunological assay technique making use of an enzyme bonded to a particular antibody or antigen
4
Q
Direct ELISA Assay
A
The surface of the plate is coated directly with the sample. An enzyme-tagged antibody enables its measurement
5
Q
Indirect ELISA Assay
A
Indirect ELISA is a two-step binding process involving the use of a primary antibody and a labeled secondary antibody
6
Q
Competitive ELISA
A
In competitive enzyme immunoassays, the antigen in a sample competes for limited antibody binding sites with antigen conjugated to a reporter enzyme. This produces an inverse relationship between antigen concentration and substrate turnover. Competitive ELISAs typically use a single antibody to a low molecular weight antigen
7
Q
capture assay
A
an enzyme immunoassay using two antibodies; the first binds the antigen to solid phase, and the second contains the enzyme label and acts as an indicator
8
Q
A low NAD+/NADH ratio drives what?
A
having more reduced NADH (NAD+) drives fatty acid synthesis because NAD+ is used to generate ATP which is required for fatty acid synthesis
9
Q
Tollen’s reagent
A
Tollen’s reagent is an oxidizing agent used to determine the presence of aldehydes and ketones *add functional groups to quizlet
10
Q
DNA stop codons
A
TAA, TAG, TGA
11
Q
RNA stop codons
A
UAA, UAG, UGA
12
Q
add amino acids
A
amino acids
13
Q
this amino acid can be used for gluconeogenesis
A
proline
14
Q
Where does the Krebs cycle (also TCA cycle and citric acid cycle) occur?
A
mitochondrial matrix (inside)
15
Q
Krebs Cycle (Citric Acid Cycle)
A
The Krebs Cycle, also known as the citric acid cycle, takes place in the matrix of the mitochondria. In the Krebs Cycle, each of the two acetyl coenzyme A molecules enter the cycle and combine with oxaloacetate to form citric acid, which then loses two carbons as carbon dioxide. The cycle is now ready to begin again with the second Acetyl CoA. For each Acetyl CoA, the Krebs Cycle produces 1 ATP, 3 NADH, and 1 FADH2.
16
Q
Krebs cycle
A
breaks down glucose following glycolysis (which occurs in the cytoplasm)
17
Q
Pyruvate
A
Three-carbon compound that forms as an end product of glycolysis. 2 pyruvate for each glucose
18
Q
pyruvate has to be actively transported
A
from cytoplasm to matrix for krebs cycle
19
Q
pyruvate dehydrogenase
A
converts pyruvate to acetyl-CoA (which then enters the krebbs cycle) - stimulated by insulin - inhibited by acetyl-CoA
20
Q
Acetyl CoA
A
is a precursor for fatty acid synthesis and is generated in the mitochondria but enzymes for FA synthesis are in the cytoplasm so acetyl coA has to be changed into citrate to be transported beck into cytoplsm transforming citrate back to acetyl coA generates acetyl coA and oaxaloacetate (which can be changed into pyruvate which can be used for glycolysis)
21
Q
NADPH
A
reducing agent to help with anabolic reactions
22
Q
anabolic
A
building up (uses ATP)
23
Q
cofactor
A
A nonprotein molecule or ion that is required for the proper functioning of an enzyme. Cofactors, mostly metal ions or coenzymes, are inorganic and organic chemicals that assist enzymes during the catalysis of reactions
24
Q
ATP hydrolysis
A
energy released, loses phosphate
25
fatty acid oxidation
Fatty acid oxidation is the mitochondrial aerobic process of breaking down a fatty acid into acetyl-CoA units
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add all orgo functional groups
orgo functional groups
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Isomer
Compounds with the same formula but different structures.
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amino acid residue
an amino acid in a polypeptide that is not the N or C terminal AA. This refers to every amino acid in a polypeptide chain.
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fructose has a
ketone (is a ketose)
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glucose, galactose, and ribose are all
aldoses
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aldehydes are more reactive to oxidation than
ketones
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Pyrimidines
Cytosine and Thymine
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visualization of an antigen of interest in an immunoassay requires labeling of antibodies with...
1. flourophores 2.enzymes 3. radioisotopes 4.biotin 5.small peptides NOT large proteins like Albumin
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transmembrane proteins
two hydrophilic portions and one hydrophobic portion, provide about 50% of the drug targets
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monotopic proteins
only on one side of the membrane
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globular proteins
these are compact, generally rounded, and soluble in water.
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fibrous proteins
long, insoluble, structural proteins.
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The reduced form
a gain of H bonds and a decrease in oxidation state
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tertiary structure of protein
Defined by the hydrophilic, ionic and hydrophobic interactions between R groups of amino acid chains.
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secondary structure of protein
alpha helix and beta pleated sheet, determined by H bonds
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primary structure of protein
the amino acid sequence of the polypeptide chain
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phosphate groups
negatively-charged groups that store the energy in ATP -found in ATP, ADP, and DNA/RNA backbone
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Testosterone
steroid hormone, not charged, can pass through the plasma membrane
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amine hormone
Amino acids with modified groups Ex. Norepinephrine
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peptide/protein hormones
-Chains of amino acids -short-acting -promote second-messenger cascades -soluble in water (polar) ex. oxytocin
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protein hormone
long chains of linked amino acids ex. human growth hormone
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steroid hormones
-derived from cholesterol, nonpolar -share cholesterol's fused-ring hydrocarbon structure -signaling molecules that bind to their receptors in the nucleus and impact transcription ex. testosterone, progesterone, estrogen
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Histone
protein molecule around which DNA is tightly coiled in chromatin histones are usually positively charged which attracts them to to the negative DNA backbone
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ATP hydrolysis
releases energy because the ATP structure is unstable because of the close phosphate groups
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insulin
A peptide/protein hormone (made of amino acids aka polar) produced and secreted by the Beta cells of the pancreas. Insulin targets cells in the body, especially the liver and muscle, and allows them to take glucose out of the blood (thus lowering blood glucose levels).
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memmorize all the
amino acids
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pyrimidines
can be metabolized into malonyl-coA by being fed into the citric acid cycle and used to generate NADH/FADH2
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ketogenic amino acids
leucine and lysine -meaning they do not produce intermediates that can be converted to glucose
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glucogenic amino acids
amino acids that can be used to form glucose They are: A, R, N, D, C, E, G, H, V, M, P, and S DARN CHEG VMPS
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formation of a disulfide bond occurs through
oxidation
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a carbonyl carbon is a classic ______________ due to the electron withdrawing effect of the double-bonded carbonyl oxygen
electrophile
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______ is the nucleophile that attacks during the peptide bond formation
the amino terminal nitrogen
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things used to denature proteins:
1. heat 2.pH 3.inorganic salt solution (an enzymatic inhibitor would not be used to denature a protein)
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look up gabriel synthesis
involves sn2 mechanism (look up diff between sn1 and sn2)
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SN1 and SN2 https://www.masterorganicchemistry.com/2012/08/08/comparing-the-sn1-and-sn2-reactions/
SN1 involves carbocation formation which is the rate-limiting step, nucleophile can attack on either plane of sp2 C, so both enantiomers can form SN2 involves backside attack, so inversion of configuration with pentavalent transition state unimolecular nucleophilic substitution (SN1), whereby the rate determining step is unimolecular and bimolecular nucleophilic substitution (SN2), whereby the rate determining step is bimolecular SN1 on 2/3 degree carbons only (carbocation stability!), SN2 on 0/1/2 degree carbons only SN1 considerations: 1. doesn't consider nucleophile size/conc. in rate law 2. *polar, protic solvent* 3. 2/3 degree carbons only SN2 like *polar, aprotic solvents*: acetone, DMF, DMSO alcohols and ethers undergo substitution only with an acid catalyst or conversion to a better leaving group (something resonance stabilized maybe) "Protic" Solvents Have O-H or N-H Bonds And Can Hydrogen-Bond With Themselves. "Aprotic" Solvents Cannot Be Hydrogen Bond Donors
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catalytic site
reduces chemical activation energy
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orthosteric regulation
regulator binds in active site
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allosteric regulation
regulator binds at non-active site
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oxidoreductases
catalyze oxidation-reduction reactions ex. alcohol dehydrogenase superoxide dismutase
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transferases
transfer functional groups between molecules ex. aspartate transaminase creatine kinase DNA polymerase
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hydrolases
catalyze hydrolysis ex. angiotensin-converting enzyme pancreatic lipase lactase
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lyases
cleave bonds through non-hydrolysis mechanisms ex. pyruvate decarboxylase aconitase
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isomerases
catalyze isomerization ex. ribose-5-phosphate isomerase
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ligases
join molecules together with covalent bonds ex. aminoacyl tRNA synthetase glutamine synthetase pyruvate carboxylase
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phosphatases _______ phosphate groups, while kinases_______ phopshate groups
remove, add
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cooperativity
It amplifies the response of enzymes to substrates, sigmoidal curve
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Hill coefficient
A measure of cooperative interaction between protein subunits if >1 then binding of each ligand is easier and positive cooperativity if <1 then binding of each successive ligand is harder and negative cooperativity (inhibition)
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Km constant in the Michaelis-Menten equation
the concentration of substrate that corresponds to half of vmax (max velocity of the reaction)
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michaelis-menton equation
V=Vmax[S]/Km+[S]
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Km is important because
it can be used as a measure of the affinity that an enzyme has for its substrate
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km is not affected by _______ but is affected by __________
not: the concentration of the substrate or enzyme Is: inhibitors
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competitive inhibitors
-compete with the substrate -do NOT affect Vmax because by adding more substrate you can minimize the effect of the competitive inhibitor -DO affect Km because their effects can be neutralized with extra substrate, but adding the extra substrate requires more substrate to reach half of Vmax, which by definition means increasing Km
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noncompetitive inhibitors
-interact with the enzyme allosterically -essentially prevent the enzyme from working -effect is similar to reducing the concentration of the enzyme that is present -DOES reduce Vmax -does NOT affect Km because the molecules of enzyme that are not affected by the noncompetitive inhibitor remain functional
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uncompetitive inhibitors
-interact with the enzyme-substrate complex at an allosteric site, essentially prevent an enzyme from letting go of a substrate that it has bound -Vmax decreases bc the overall rate of the catalyzed reaction is reduced -decrease in Km because the stabilization of the E-S complex effectively means that the enzyme seems to have a greater affinity for the substrate
80
mixed inhibition
-inhibitor can either -can bind the free enzyme at an allosteric site or can bind the E-S complex -Vmax is always decreased -its effect on Km depends on the binding preference of a given inhibitor if prefers binding to E-S complex: similar to an noncompetitive inhibitor so Km will be decreased if prefers binding to the free enzyme at an active site (allosteric I think)**??? then Km is increased tim said: The correct answer is that a mixed inhibitor may bind the active site of the free enzyme (like a competitive inhibitor) or to an allosteric site on the enzyme-substrate complex (like an uncompetitive inhibitor (note: not the same as a non-competitive inhibitor). Depending upon the inhibitor's "preference" for binding free E or E-S complex, you will get an effect that "mimics" a competitive or non-competitive inhibitor.
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phosphorylation most commonly targets
serine, threonine, and tyrosine which all have -OH groups that the phosphate group can be attached to
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zymogens or proenzymes
are produced in their inactive form and can be activated by cleavage at a later time when they are needed
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cofactors or coenzymes (organic cofactors)
are required for the enzyme to be activated
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Kinetic efficiency
a measure of how efficiently an enzyme converts substrates into product Kcat/Km highest ratio=highest efficiency
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homogenate
a mixture of all of the components of the cell, but no intact cells.
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Warberg effect
cancer cells rely on anaerobic glycolysis instead of ox phos (more efficient) to generate energy
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primary active transport
Active transport that relies directly on the hydrolysis of ATP.
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secondary active transport
Form of active transport which does not use ATP as an energy source; rather, transport is coupled to ion diffusion down a concentration gradient established by primary active transport.
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Microfilaments
Long, thin fibers that function in the movement and support of the cell
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Microtubules
Spiral strands of protein molecules that form a tubelike structure
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intermediate filaments
A component of the cytoskeleton that includes filaments intermediate in size between microtubules and microfilaments.
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antibody IgA
-present in mucosal areas such as the gut, respiratory tract, saliva, tears, breast milk, and the urogenital tract, -it helps prevent colonization by pathogens
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antibody IgD
-principally acts as an antigen receptor on B cells that have not been exposed to antigens -it is involved in the activation of mast cells and basophils
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antibody IgE
-involved in allergies and anti-parasitic responses -IgE binds to allergens, causing histamine release from activated mast cells and basophils
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antibody IgG
-four forms of IgG provide most of the humoral immune response -it is the only antibody type capable of crossing the placenta and conferring passive immunity to a developing fetus
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antibody IgM
-the first antibody secreted upon exposure to an antigen -responsible for mounting an immune response and eliminating pathogens in the early stages of the humoral response, before IgG levels increase -it is expressed on the surface of B cells as a monomer and is secreted by plasma cells as a pentamer
97
CAMs
cell adhesion molecules
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Cytokines
-Chemicals released by the immune system communicate with the brain. -signaling molecules of the immune system
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motor protein: Kinesins
move towards the (+) end of microtubules (towards the periphery), transport vessicles and organelles by travelling along microtubules, which requires the hydrolysis of ATP
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motor protein: dyneins
carry cargo xtowards the (-) end of microtubules (towards center)
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motor protein: myosin
involved in muscle contractions, use ATP to carry out power stroke
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antibodies
-glycoproteins that recognize antigens (characteristic regions, usually of foreign objects/substances) -composed of at least one immunoglobulin (Ig) unit, each of which has two heavy chains and two light chains, forming a Y shape -several types exist; most important are IgM antibodies, which respond to acute infections, and IgG antibodies, which help confer lasting immunity
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cell adhesion
proteins involved include selectins, cadherins, and integrins
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cell adhesion: anchoring junctions
involve cadherins, help keep cells/tissues in place
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cell adhesion: gap junctions
formed by connexin proteins, connect cells in a way such that diffusion/communication can take place between them
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cell adhesion: tight junctions
involve several types of proeteins, are found in epithelial cells, and prevent solutes from being able to move freely from one tissue into another classic example: blood-brain barrier
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ion channel-linked receptors:
-also known as ligand-gated ion channels -change shape in response to binding with a ligand to open and let ions through
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enzyme-linked receptors
-either enzymes themselves, or are directly associated with the enzymes that they activate -majority are protein kinases, and regulate many normal cellular processes
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G protein-coupled receptors
-composed of three distinct alpha, beta, and gamma subunits -they become activated by binding with GTP -the alpha subunit together with the bound GTP dissociates from the beta and gamma subunits, which interact with other signaling processes in the cell (secondary pathways)
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nuclear receptors
-found within the cell (either on the nucleus or in the cytosol before travelling to the nucleus) and regulate gene transcription in response to binding with a signaling molecule (often a steroid hormone)
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specificity constant of the interaction between two molecules
kcat/km
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Kcat
turnover number (molecules catalyzed per second in optimal conditions) Vmax / [E]
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actin filaments
can be assembled in a branched pattern (while microtubules cannot)
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Goldberg-Hogness box (TATA box)
A short nucleotide sequence 20-30 bp upstream from the initiation site of eukaryotic genes to which RNA polymerase II binds. The consensus sequence is TATAAAA. Also known as a TATA box. promoter for transcription
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kinetochore
-protein complex assembled at each centromere -serves as an attachment site for spindle microtubules and the site at which motors generate forces to power chromosome movement
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spindle poles
ends of spindles (specialized microtubules that captures and separates chromosomes)
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centriole
Made of bundles of long filaments called microtubules that help in organizing cell division, radiate in star-shaped clusters known as asters which help align chromosomes during cell division
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Centromere
Area where the chromatids of a chromosome are attached
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Immunoglobulin M (IgM) contains
two heavy chains and two light chains
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cadherins
cell adhesion molecules that comprise adherens junctions and serve to connect cells to eachother (transmembrane proteins)
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dyneins
require ATP, involved in retrograde transport of cargo (movement towards center of the cell)
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G proteins
activated by substitution of GDP for GTP, but deactivated when GTP is hydrolyzed to GDP by GTPase
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look up a video on titration
each half equivalence point signifies a functional group
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look up cation exchange chromatography
In cation-exchange chromatography, positively charged molecules are selectively purified via binding to an anionic solid phase. Thus, for this amino acid to be purified in this manner, it must have a net positive charge. adding more base means the unknown amino acids will be less positive, just as a concept
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linking of amino acids
Polypeptides are formed via dehydration synthesis reactions that link amino acids with peptide bonds. The incoming amino group acts as a nucleophile and attacks the carbonyl carbon, and the labeled hydrogen molecule (along with the O to which it is directly bound) is released as water.
126
ion exchange chromatography
Ion-exchange chromatography separates compounds based on net charge. In this case, the stationary phase is negative, meaning that positive compounds will be retained in the column. In other words, these species will elute more slowly because they will interact more with the stationary phase. Therefore, we would expect the polypeptide that elutes first to contain fewer positively-charged residues than the one that elutes second. Arginine (R) is positively charged at physiological pH, so it is unlikely to be common in the polypeptide referenced.
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protein tertiary structure
Tertiary structure is driven by the tendency of hydrophobic residues to bury themselves inside the protein, away from aqueous environments, as well as side chain interactions such as hydrogen bonding and disulfide bridges. We can therefore expect that a substitution between amino acids that vary in polarity, charge, or sulfur content might change this level of structure. Of all the replacements listed, exchanging glycine (a nonpolar, neutral residue that lacks sulfur) with cysteine (a polar AA with the ability to participate in disulfide bridges) is most likely to cause a change in tertiary structure.
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the only amino acid that can for disulfide bonds is... because it has...
cystein, a free -SH group
129
look up what makes something aromatic
Aromatic compounds are those that contain planar, conjugated rings and follow Hückel's rule, which stipulates that the system must possess 4n + 2 π electrons. (To simplify this rule, remember that "n" denotes any integer, meaning that aromatic systems may contain 6, 10, or 14 π electrons, and so on.) Tyrosine, a classic example of an aromatic amino acid, fits all of these qualifications.
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enzymes affect the ______ not the _______ of a reaction
kinetics, thermodynamics
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spontaneous v non spontaneous reactions
As a rule of thumb, remember that exergonic reactions (ΔG < 0) are spontaneous, while endergonic processes (ΔG > 0) are nonspontaneous
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energy-rich compunds
ATP, creatine phosphate, and acetyl-CoA are all similar in that they contain high-energy phosphate or thioester bonds. used to couple to and drive nonspontaneous reactions
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second law of thermodynamics
he second law of thermodynamics states that a spontaneous reaction or cyclic process must yield a net entropy increase.
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first law of thermodynamics
Energy can be transferred and transformed, but it cannot be created or destroyed.
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Third Law of Thermodynamics
The entropy of a perfect crystal is zero when the temperature of the crystal is equal to absolute zero (0 K).
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Gibbs free energy
ΔG = ΔH - TΔS, where ΔH represents the change in enthalpy, T denotes Kelvin temperature, and ΔS denotes the change in entropy.
137
ATP equivalents of NADH and FADH2
NADH=2.5ATP FADH2=1.5ATP (because FADH2 enters the ETC one complex later than NADH)
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Enantiomers
isomers that are mirror images of each other, but not superimposable
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which enantiomer is present in the human body
L
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Anion exchange chromatography
Negative proteins stick to positive beads, only positive proteins go through (name describes what it captures/what elutes last)
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pI
net charge of a protein will be zero
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SDS-PAGE
Type of chromatography used to separate proteins based on mass.
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Beer-Lambert Law relationship between absorbance, extinction coefficient, concentration, and path length
absorbance = εCL. Here, ε represents the extinction coefficient, C denotes the concentration of the solution, and L stands for the path length in centimeters
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SDS-PAGE
breaks up proteins into its subunits
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critical pont
the the concentration where the length of the polymer is sable (no net polymerization or depolarization occurs)
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the ___ ends of actin molecules display stronger intermolecular interactions than the ______ ends
#ERROR!
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microtubules originate from
microtubule-organizing centers, or MTOCs, these structures anchor the minus end of the microtubule to prevent depolymerization, they aslo form the origin of the spindle aparatus during cell division
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variable region of antibody
-antigen binding site, is specific to the antigen -includes the ends of the light and heavy chains
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constant region of an antibody
the constant region determines the mechanism used to destroy antigen, this region can be recognized by other immune components to further stimulate the response to a pathogen
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dynein transport
-travel toward the center of the cell -move toward the minus ends of the associated microtubules -are involved in retrograde transport
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vitamin E
antioxidant. Essential for protection of cell structure, especially of red blood cells
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vitamin A
regulator of tissue growth
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Vitamin B
The B vitamins are the largest group of vitamins and function in the production of multiple cofactors. Biotin is a B vitamin that acts as an important coenzyme, while riboflavin serves as a structural part of the cofactors FMN and FAD
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Vitamin D
influence over bone growth and calcium regulation
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NAD is a
Coenzyme Coenzymes are a subset of cofactors that tend to bind loosely to their associated enzymes. This type of molecule is also known for transferring functional groups between species. NAD serves this function by donating its hydrogen to Complex I, which is one of the four protein complexes responsible for generating the proton gradient during aerobic cellular respiration.
156
prosthetic groups
small molecules permanently attached to the enzyme, tightly bound
157
Km
is simply the substrate concentration at which reaction rate is equal to one-half of the Vmax
158
disulfide linkages are cleaved exclusively via
oxidation/reduction reactions
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SDS (of SDS-PAGE)
disrupts secondary and tertiary protein structure and applies a uniform negative charge across the protein
160
immunoaffinity
uses antibody-protein affinity to retain the desired substrate on the solid phase matrix
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salting in
-refers to the addition of salt to a solution that does not yet contain very high salt concentrations -the salt interacts with charged amino acid side chains, reducing the protein's ability to aggregate with other proteins -the net result is increased protein solubility
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the presence of _______ amino acids in a protein cause the protein to absorb ultraviolet light whose wavelength range is: the aromatic amino acids are:
aromatic, 200-400nm Tyr, Trp, Phe
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in cation exchange chromatography, ______ will elute first
anions -the stationary phase is designed to attract cations (so it is comprised of anions)
164
transition state
it is always is a higher energy state than the reactants or products. Thus any time the transition state is stabilized, activation energy (which by definition is the energy required to reach the transition state) is reduced. The more stable a transition state is, the less energy is required to reach it which makes it easier to go from the reactants to the final product.
165
Angiotensinogen
- zymogen precursor to angiotensisn, a peptide hormone that leads to vasoconstriction -produced in the liver
166
make flashcards for these:
FLAG TOP, PAVO, PIGS, ACAC, and THC. FLAG TOP for things coming from anterior pituitary (Fsh, Lh, Acth, Growth Hormone, Tsh, MelOncyte stimulating hormone, prolactin) for posterior pituitary I remember PAVO (Posterior, Adh/Vasopressin, Oxytocin) for the pancreas I remember PIGS (Pancreas, Insulin, Glycogen, Somatostatin) for the thyroid I remember THC like in marijuana (Thyroid Hormone, Calcitonin) and for adrenal cortex I remember ACAC (Adrenal Cortex, Aldosterone, Cortisol)
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make flashcards for these hormones
These are all the hormones that must be memorized for the MCAT. Learn the 5 steroid and know the rest are protein, know where there are secreted from (in the case of oxytocin and vasopressin (or antidiuretic hormone) know they are made in the hypothalamus and secreted to the posterior pituitary where they are stored and later secreted.Steroid:Testosterone (Androgen): TestesProgesterone: Ovary specifically corpus luteumEstrogen: ovary specifically follicleAldosterone: adrenal cortexCortisol: adrenal cortexProtein:Follicle stimulating hormone: anterior pituitaryLeutinizing hormoneACTHThyroid stimulating hormone (TSH)ProlactinGrowth hormoneOxytocin: posterior pituitaryVasopressinInsulin: pancreasGlucagonParathyroid hormone: parathyroidCalcitonin: thyroidThyroxineEpinephrine: Adrenal MedullaNorepinephrine
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hypophyseal portal system
blood leaving capillary beds in hypothalamus travels to a capillary bed in anterior pituitary to allow for paracrine secretion of releasing hormones
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-dioic acid
2 carboxylic acids
170
epimers
are carbohydrates which differ in their configuration of a single chirla center
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memorize carbohydrates on pg16 of bio
there is a chart
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Tollen's reagent, like Benedict's reagent, is used to
test for reducing sugars (it oxidizes an aldehyde into a carboxylic acid) Reducing sugars have free aldehyde groups that can be oxidized to caroxylic acids, which reduces the tollens reagent to elemental silver
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Anomers
specific category of epimers, which are stereoisomers that differ in only one chiral center (ex. in solution glucose readily undergoes mutarotation between its alpha and beta anomers)
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specific rotation
-an experimental value -generally, the specific rotation of a particular compound does not relate in any predictable way to that of another compound except enantiomers have equal but opposite specific rotation values and racemic solutions have a specific rotation of 0 degrees
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Fisher Projection
horizontal=out of the paper vertical= into the paper
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enzymes have chiral active sites so
if D-glucose is normally acted on by an enzyme, that enzyme could not work on L-glucose
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hemiacetal
A functional group that contains a carbon atom bonded to one -OR group, one -OH group, an alkyl chain, and a hydrogen atom.
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pyranose v furanose
six-membered rings=pyranoses five-membered rings=furanoses
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anomer
A sugar diastereomer differing only in the position of the hydroxyl at the anomeric carbon (the one attached to the OH)
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glycosidic bond
A glycosidic bond is a covalent bond in which a carbohydrate binds to another group, which could also be a carbohydrate. A glycosidic bond is found between the two glucose molecules in maltose.
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peptidoglycan
A protein-carbohydrate compound that makes the cell walls of bacteria rigid, consists of carbohydrates that have been modified with amino acids
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Chitin
Polysaccharide found in arthropod exoskeletons and fungal cell walls.
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optical rotation of light
d/l or +/-
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absolute configuration
-R/S -determined by the 3D arrangement of the groups attached to the chiral carbon
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comparing longer-chain carbohydrates to the three-carbon substance glyceraldehyde
D/L (different than the d/l system and does not have anything to do with how light is rotated)
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D/L
-any carbohydrate in which the bottom most -OH in the Fisher projection is pointing right is D and pointing left is L -most carbohydrates in living organisms are D isomers
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the alpha helical structure of a protein is held together by which of the following?
hydrogen bonding between carbonyl oxygen and amino hydrogen atoms
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Squalene
-is a terpene, or a compound composed of isoprene (C5H8) units -do not contain oxtgens -precursor to cholesterol
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family of receptors that allow glucose into the cells
GLUT receptors
190
GLUT 1
receptor that allows glucose into the cell -is expressed throughout the body and is responsible for constant low-level baseline glucose intake
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GLUT 2
receptor that allows glucose into the cell -expressed by liver, pancreatic beta, and kidney cells -bidirectional transporter (both in and out of the cell)
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Bacterial cells ______ carry out post-transcriptional modification of mRNA.
cannot
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cDNA
Complementary DNA. DNA produced synthetically by reverse trascribing mRNA. Because of eukaryotic mRNA splicing, cDNA contains no inrons.
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dsDNA
double stranded DNA
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ssDNA
single stranded DNA
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all of these are true about the major groove
I. The major groove offers more space for the enzymes to access the sides of the bases. II. In the minor groove, the enzymes would be unable to tell the difference between an A-T and a T-A pair. III. The enzymes cannot bind to phosphate groups in the DNA backbone in a sequence-specific way
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What is the principle contributor to DNA helix stability?
hydrophobic effect
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Western Blotting
Western blotting is a technique in which proteins are run on a gel using electrophoresis, transferred to a nitrocellulose or similar membrane, and finally washed with an antibody marker. It is typically used to determine the identity of particular proteins present in a sample and can sort these proteins by molecular weight.
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Northern blots
detect the presence of mRNA, not protein.
200
Southern blots
identify particular DNA sequences. The question asked about the detection of protein.
201
PCR, or a polymerase chain reaction
is used to amplify DNA sequences of interest. It is not a detection method.
202
Embryonic cells are
pluripotent, meaning that they can give rise to virtually any cell type found in the human body. In contrast, adult stem cells are multipotent, so their development is much more restricted. Multipotent cells can still develop into more than one cell type (for example, a variety of blood cells), but embryonic cells are still more widely useful.
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Immunohistochemistry
uses antibodies that are specific to proteins in an attempt to determine which antigens are expressed in a particular region of tissue. This technique has particular applications to cancer research.
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Flow cytometry
measures physical and chemical characteristics of cells
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restriction fragment length polymorphism (RFLP) analysis
providing a detailed and visual report on the protein expression within a tissue
206
SDS-PAGE procedure assure that the difference in running distance on the gel is due to the length of the peptide and not its shape?
SDS is a detergent, meaning that it has both a hydrophobic and a hydrophilic end, like soap. This substance coats the protein and destroys hydrophobic interactions, largely denaturing all but primary structure. As a result, the protein can move through the gel in a linear fashion, removing its shape as a potential confounding variable.
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In a western blotting procedure
the proteins in the original mixture are first separated on an SDS-PAGE gel. Typically, in addition to SDS, a reducing agent is used to break disulfide bonds that may be present between cysteine residues. Next, antibodies are used to detect particular species.
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double check- what tim says about effector v inducer
There's a subtle distinction between the two terms: from what I understand, effectors are molecules that bind to the protein and regulate its activity (aka post-translational regulation). Inducers are molecules that bind to the DNA sequence at activator or repressor sequences (aka transcriptional regulation).
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https://www.youtube.com/watch?v=vRBOv4RR7y8 shows an enhancer at work. Enhancers are DNA sequence that interact with the transcription complex to increase transcription.
look at video
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Glycolysis net reaction
Glucose + 2Pi + 2ADP + 2NAD+ -> 2pyruvate + 2ATP + 2NADH + 2H+ + 2H2O
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homolactic fermentation
produces lactic acid only, occurs in skeletal muscle
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heterolactic fermentation
produces a mixture of lactic acid, ethanol, and/or acetic acid and CO2 because the bacteria uses the branched pentose phosphate pathway instead of the standard pathway for glycolysis
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most common products of fermentation are
lactic acid, ethanol, methane gas, and hydrogen gas pyruvic acid is a key intermediate that is a reactant in fermentation and not a product
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Angiogenesis
formation of new blood vessels
215
human fermentation uses:
lactate dehydrogenase
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alcoholic fermentation uses:
pyruvate decarboxylase and alcoholic dehydrogenase, produce carbon dioxide and ethanol
217
aerobic respiration cannot take place if:
-the cell lacks sufficient final electron acceptor -the cell lacks genes to make appropriate complexes and electron carriers in the electron transport system -the cell lacks DNA to make one or more enxymes needed in the aerobic pathway (ex. citrate synthase)
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Erythrocytes
or red blood cells, do not contain a nucleus or mitochondria. Therefore, they cannot use the Krebs cycle or electron transport chain to create ATP
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mast cells
found in the connective tissue of the dermis; respond to injury, infection, or allergy by producing and releasing substances, including heparin and histamine
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In glycolysis, what is the net yield of ATP per molecule of pyruvate produced?
1 ATP In its entirety, one "round" of glycolysis requires two ATP molecules and produces a total of four. In other words, glycolysis forms a net quantity of two ATP molecules per original molecule of glucose. However, glucose is split into two molecules of pyruvate, the end product of the glycolytic pathway. For this reason, only one ATP molecule is made per unit of pyruvate.
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net reaction of glycolysis
Glucose + 2 NAD+ + 2 ADP → 2 pyruvate + 2 NADH + 2 ATP so ADP is essential for glycolysis to occur
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One hour after a meal, what is the expected saturation status of hexokinase and glucokinase with glucose?
Hexokinase has a much higher affinity for glucose than its isozyme, glucokinase. However, at high glucose concentrations, both enzymes should be saturated with glucose.
223
Glycolysis includes three irreversible steps
these are catalyzed by hexokinase, phosphofructokinase, and pyruvate kinase Note that the first irreversible reaction (promoted by phosphofructokinase) is often termed the committed step, though some sources call all three steps "committed."
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sugars that can enter glycolysis
glucose and fructose
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During the synthesis of malate...
fumarate experiences the addition of water across its double bond. This results in the replacement of this bond with an -OH group on one carbon and a hydrogen atom on the other. Such a process represents a classic hydration reaction.
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Decarboxylation
The complete loss of a carboxyl group as carbon dioxide
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during the krebs cycle how many NADH and FADH 2 are produced?
During the Krebs cycle, each unit of acetyl-CoA forms three molecules of NADH and one molecule of FADH2. In other words, the NADH-to-FADH2 ratio is 3:1.
228
Throughout both the Krebs cycle and oxidative phosphorylation, how many molecules of ATP are formed per molecule of acetyl-CoA?
10 Acetyl-CoA is fed into the Krebs cycle to produce three NADH, one FADH2, and one GTP molecule, the last of which is immediately converted to ATP. Each NADH is later used to form 2.5 ATP molecules, while the single FADH2 unit is utilized to synthesize 1.5. In total, 12 molecules of ATP are created (counting GTP as an ATP equivalent).
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Subunits of ATP Synthase-which one rotates
gamma subunit rotates
230
NADH enters at complex
I
231
FADH2 enters ETC at complex
2
232
NADH produces
2.5 ATP
233
FADH2 produces
1.5 ATP
234
Gluconeogenesis occurs in the
liver (mainly) and kidneys
235
primary function of the pentose phosphate pathway
The primary function of the pentose phosphate pathway is to generate large quantities of NADPH for use in anabolic reactions. Without NADPH, numerous critical pathways would be hindered, including nucleic acid and fatty acid synthesis. This would directly impact the viability of the cell.
236
The pentose phosphate pathway is likely most active in the
liver One of the primary functions of the pentose phosphate pathway is to produce NADPH, which is used in fatty acid synthesis. Fatty acid formation from carbohydrates occurs predominately in the liver
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What would be the expected effect on the pentose phosphate pathway during times of starvation
The starting molecule for the pentose phosphate pathway is glucose 6-phosphate. Most glucose that is ingested will be phosphorylated to form this species. During periods of starvation, glucose (both that acquired externally and that synthesized internally) is relatively unavailable. Thus, the pentose phosphate pathway should occur less frequently due to lower levels of glucose 6-phosphate.
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for MCAT a high ADP to ATP ratio or high NAD+/NADH ratio is the same as
needs more energy so glycolysis, citric acid cycle, and eETC are upregulated
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citric acid cycle
-pyruvate dehydrogenase complex (PDC) convertspyruvate to Acetyl-CoA before entering citric acid cycle (produces 1 NADH) -net producs of the citric acid cycle per turn: 1 GTP, 3NADH, 1 FADH, 2 CO2 -first step is Acetyl-CoA combining with oxaloacetate to form citrate
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ETC
Unlike coenzyme Q, which carries two electrons, cytochrome c carries only one electron.
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Which key intermediate of the citric acid cycle connects it with gluconeogenic pathways?
malate during gluconeogenesis, oxaloacetate in the mitochondria is convertes to malate for export from the mitochondria, cytosolic malate is then re-oxidized to oxaloacetate and converted to phosphophenyl pyruvate (this step is almost always rate limiting in gluconeogenesis) malate is also a citric acid cycle intermediate
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Each turn of the Krebs cycle produces
1 GTP ; 3 NADH ; 1 FADH2 ; two CO2 are lost as waste [it turns once for each pyruvate produced by glycolysis]
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what is the irreversible, rate-limiting step of the citric acid cycle?
the generation of the five-carbon molecule alpha-ketoglutarate, this step is catalyzed by the enzyme isocitrate dehydrogenase
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of protons transferred in each complex in the ETC
complex 1 -4 complex 2 -0 complex 3 -4 complex 4 -4 separate, but still remember: coenzyme Q- carries 2 electron cytochrome c-carries 1 electron
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What metal ion is found in cytochrome c?
Fe, just like in Hemoglobin
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Eicosanoids
lipids derived from arachidonic acid include: prostaglandins-modulate inflammation thromboxanes-involved in clotting
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LDL and HDL are not different types of cholesterol, but are rather...
are lipoproteins that are cholesterol transporters ldl=bad hdl=good
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Chylomicrons
the class of lipoproteins that transport lipids from the intestinal cells to the rest of the body
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carnitine shuttle
mechanism for moving fatty acids from the cytosol to the mitochondrial matrix as fatty esters of carnitine takes acyl-coA and replaces the acyl to carnitine, then restores one in matrix
250
energy output of beta oxidation=
a little less than 7n n- number of carbons in the fatty acid chain
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fatty acid synthesis takes place in the
cytosol
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Fatty acid synthesis
ACC makes malony coA which binds to the acyl carrier protein (ACP) where the acetyl coA and malonyl coA condense to form the 4C cabone chain (this step releases CO2) then more acetyl coA parts are added and reduced, this requires NADPH (NADPH is generated by the pentose phosphate pathway)
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this enzyme catalyzes the committed step in fatty acid synthesis: the production of malonyl CoA
acetyl coA Carboxylase (ACC)
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Pentose Phosphate Pathway
A metabolic process that produces NADPH and ribose 5-phosphate for nucleotide synthesis.
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Cholesterol
mainly derived from diet, but can also be made de novo in the liver cholesterol synthesis is similar to fatty acid synthesis, in the first step the 6 carbon compound called mevalonate is formed from acetyl-coA molecules joining and a reduction cooupled with NADPH, this is the rate-limiting step of cholesterol synthesis summary of cholesterol synthesis: mevalonate->repeating isoprene units->squalene->cholesterol *mevalonate is the rate limiting step
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Pyruvate
Three-carbon compound that forms as an end product of glycolysis.
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Acetyl CoA
Acetyl coenzyme A; the entry compound for the citric acid cycle in cellular respiration, formed from a fragment of pyruvate attached to a coenzyme.
258
Where does fatty acid oxidation occur?
mitochondria (oxidation is the breakdown)
259
How do ketone bodies become ATP in the brain?
they are converted into acetyl-CoA which enters the TCA cycle directly
260
What are the molecules in the plasma membrane made of?
phospholipids are made of a glycerol backbone covalently bound to two fatty acids and a phosphate group
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Where do HDL and LDL bring cholesterol?
LDL-transports to body tissues HDL-transports to liver
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What is sedimentation analysis?
sucrose and the molecule in question are centrifuged ina tube , lighter molecules move less quickly than denser molecules, each molecular type will form a discrete band at its isopycnic point, where its density equals that of the sucrose gradient
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what is the production pathways for a plasma membrane bound protein?
nucleus->cytoplasm->ribosome-RER-golgi
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change in G at equilibrium is...
0
265
What is the average molecular weight of an amino acid residue?
110 Da a Dalton is equivalent to 1 atomic mass unit (amu)
266
Which modes of transport does CO2 use in the body?
I. Binding hemoglobin II. Dissolving in the plasma
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What is the formula for turnover number?
turnover number (aka kcat) is defined as the maximum number of chemical conversions of substrate molecules per second that a single catalytic site will execute for a given enzyme concentration (ET). Turnover number can be calculated from the maximum reaction rate (Vmax) and enzyme concentration as follows: kcat = Vmax/ET
268
What is homotropic regulation?
Homotropic regulation is when a molecule serves as a substrate for its target enzyme, as well as a regulatory molecule of the enzyme's activity. O2 is a homotropic allosteric modulator of hemoglobin. The four subunits of hemoglobin actually bind to oxygen cooperatively, meaning the binding of oxygen to one of the four subunits will increase the likelihood that the remaining sites will bind with oxygen as well. causes a sigmoidal curve
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What does the hemoglobin binding curve look like and what does shifting right and left mean?
sigmoidal The higher the partial pressure of oxygen, the higher the oxygen saturation tends to be. Interestingly, under certain conditions, the binding curve can shift toward the right along the x-axis; this decreases the hemoglobin-oxygen binding affinity, allowing oxygen to be more easily dropped off in the tissues. These conditions include low (acidic) plasma pH and increased levels of carbon dioxide - both of which can indicate a shortage of oxygen. This rightward shift of the hemoglobin-oxygen binding curve is termed the Bohr effect. A compound known as 2,3-bisphosphoglyceric acid (2,3-BPG) can enhance these effects, further promoting the release of oxygen from hemoglobin.
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What is a suicide inhibitor?
an inhibitor that covalently bonds to an enzyme and then never unbinds a suicide inhibitor acts as an irreversible enzyme inhibitor. Suicide inhibition occurs when an enzyme binds the inhibitor (structurally a substrate analogue) and forms an irreversible complex with it, usually through a covalent bond. This can involve the inhibitor being chemically modified by the enzyme during the normal course of catalysis to produce a reactive group that is specifically responsible for the formation of the irreversible inhibitor-enzyme complex.
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uncompetitive inhibition
inhibitor binds only to enzyme-substrate complex locks substrate in enzyme preventing its release (increasing affinity b/w enzyme and substrate so it lowers Km) Lower Km and vmax Uncompetitive inhibition is when the inhibitor binds to only the enzyme-substrate complex, and inactivates it. This causes the number of active enzyme-substrate complexes to decrease, thereby decreasing Vmax. Km also decreases to exactly the same degree as Vmax. Since both kinetic factors decrease to the same extent, the slope of the Lineweaver-Burk plot of enzyme activity will be the same as for the uninhibited enzyme. The effects of an uncompetitive inhibitor cannot be overcome by increasing substrate concentration. Most commonly, the kinetic parameters Vmax and Km are reported via Michaelis-Menten plots. However, Lineweaver-Burk plots may also be used. When the experimental data are examined in the form of double reciprocal Lineweaver-Burk plots, the x- and y-axes are 1/[S] and 1/V, respectively. Since these plots are a straight line, the slope of each line is Km/Vmax. The y-intercept on a Lineweaver-Burk plot represents 1/Vmax, while the x-intercept is −1/Km. These double-reciprocal plots are especially useful for distinguishing between competitive and noncompetitive inhibitors.
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non-competitive inhibitor
a molecule that binds to an enzyme at a location outside the active site and inhibits the enzyme's function. Noncompetitive inhibition is when the inhibitor does not compete with the substrate for the active site, but reduces enzyme activity by binding to another site (the allosteric site) on the enzyme. In noncompetitive inhibition, the inhibitor can combine with either the enzyme or the enzyme-substrate complex. In pure noncompetitive inhibition, the value of Vmax is decreased. Since these inhibitors do not compete with the substrate, their activity is unaffected by substrate concentration. Since the inhibitor always affects a consistent proportion of the available enzyme, Vmax is reduced. However, Km remains the same since if Vmax, is reduced, Vmax/2 is reduced proportionally, and the amount of substrate required to reach this new, reduced Vmax/2 is the same as the original Km.
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Remember, pKas correspond to ___________, not equivalence points!
half-equivalence points (as shown in pic)
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hyperventilation results in?
excess CO2 being expelled from the blood, causing the pH to rise. In response, the buffer needs to release more H+ to lower the pH back to physiological norms.
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Coenzyme Q vs cytochrome C
Unlike coenzyme Q, which carries two electrons, cytochrome c carries only one electron
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Conversion of pyruvate into glucose requires enzymes present in?
both the mitochondria and the cytosol Conversion of pyruvate to glucose requires its initial conversion into oxaloacetate, in a reaction catalyzed by pyruvate carboxylase in the mitochondria. Oxaloacetate (OAA) is then decarboxylated and phosphorylated by cytosolic or mitochondrial forms of phosophoenolpyruvate carboxykinase (PEPCK). After transport of either OAA in the form of malate or PEP directly from the mitochondria, the remainder of gluconeogenesis takes place in the cytosol.
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Where does gluconeogenesis occur?
liver and kidney It is upregulated by glucagon and by the presence of surplus pyruvate/acetyl-CoA.
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How does gluconeogenesis bypass the irreversible/exergonic steps of glycolysis?
gluconeogenesis bypasses these steps using enzymes that catalyze a simple hydrolysis reaction, splitting off a Pi from the carbohydrate
279
what is the difference between kinase, phosphorylase, and phosphatase?
Adds P- kinase and phosphorylase Removes p- phosphatase
280
The formula for a straight-chain alkane is:
CnH2n+2
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aromatic compound
Aromatic compounds are conjugated cyclic molecules with a planar structure that also satisfy an additional criterion known as Hückel's rule: having (4n + 2) π-electrons, where n is an integer.
Saturated hydrocarbon formula can be confusing bc its similar CnH2n+2
282
What is the linweaver-burke plot for Competitive inhibition?
Competitive inhibition is when the inhibitor directly competes with the substrate for the active site on the enzyme. This increases Km since it now takes more substrate to ensure half of the active sites are occupied. If enough substrate is supplied, it will outcompete the inhibitor; therefore, Vmax does not change, although more substrate is needed to reach it.
283
What is the linweaver-burke plot for noncompetitive inhibiton?
Noncompetitive inhibition is when the inhibitor does not compete with the substrate for the active site, but reduces enzyme activity by binding to another site (the allosteric site) on the enzyme. In noncompetitive inhibition, the inhibitor can combine with either the enzyme or the enzyme-substrate complex. In pure noncompetitive inhibition, the value of Vmax is decreased. Since these inhibitors do not compete with the substrate, their activity is unaffected by substrate concentration. Since the inhibitor always affects a consistent proportion of the available enzyme, Vmax is reduced. However, Km remains the same since if Vmax, is reduced, Vmax/2 is reduced proportionally, and the amount of substrate required to reach this new, reduced Vmax/2 is the same as the original Km.
284
What is the linweaver-burke plot for uncompetitive inhibition?
Uncompetitive inhibition is when the inhibitor binds to only the enzyme-substrate complex, and inactivates it. This causes the number of active enzyme-substrate complexes to decrease, thereby decreasing Vmax. Km also decreases to exactly the same degree as Vmax. Since both kinetic factors decrease to the same extent, the slope of the Lineweaver-Burk plot of enzyme activity will be the same as for the uninhibited enzyme. The effects of an uncompetitive inhibitor cannot be overcome by increasing substrate concentration. Most commonly, the kinetic parameters Vmax and Km are reported via Michaelis-Menten plots. However, Lineweaver-Burk plots may also be used. When the experimental data are examined in the form of double reciprocal Lineweaver-Burk plots, the x- and y-axes are 1/[S] and 1/V, respectively. Since these plots are a straight line, the slope of each line is Km/Vmax. The y-intercept on a Lineweaver-Burk plot represents 1/Vmax, while the x-intercept is −1/Km. These double-reciprocal plots are especially useful for distinguishing between competitive and noncompetitive inhibitors.
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Microtubules are used
-in the transport of vesicles and the positioning of organelles within the cell. -microtubules form the spindle apparatus that is an essential part of both mitosis and meiosis. -they are composed of dimers of the protein tubulin
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Endoplasmic Reticulum
A system of membranes that is found in a cell's cytoplasm and that assists in the production, processing, and transport of proteins and in the production of lipids (lipids made in smooth ER).
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Golgi apparatus
A system of membranes that modifies and packages proteins for export by the cell
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Peroxisomes
Produce hydrogen peroxide; detoxify harmful substances such as ethanol and break down long fatty acids to medium length fatty acids
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microfilaments
-composed of two strands of actin polymers -play a role in cell motility -play a role in endocytosis and exocytosis -help with cell cleavage
290
Microtubules
-slightly wider than microfilaments -composed of polymeric dimers of polymers known as alpha-tubulin and beta-tubulin -maintain cell strucutre and make up cilia and flagella -facilitate intracellular transport and make up mitotic spindles
291
intermediate filaments
-structural support and cellular adhesion (ex. keratin)
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centrioles
-cylindrical structures made up of tubulin and help organize the mitotic spindle -important constituent of the centrosome (microtubule organizing center)
293
prokaryotic flagella vs eukaryotic flagella
powered by ATP in eukaryotes and bacteria powered by a rotary motion powered by a proton gradient
294
G0 phase
resting phase of cell cycle
295
interphase
broken up into G1, S, and G2 cell grows during G1 and G2 and replicates during S
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G1 checkpoint
restriction point, when a cell commits to division G2 checkpoint checks for DNA damage
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Prophase
Chromosomes become visable, nuclear envelop dissolves, spindle forms
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kinetochore
A specialized region on the centromere that links each sister chromatid to the mitotic spindle.
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telophase
opposite of prophase -new nuclear envelope, nucleolus reappears with nucleus
300
Prokaryotic translation relies on the presence of several release factors.
In contrast, eukaryotes need only one such factor: eukaryotic translation termination factor 1 (eRF1).
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histones in human nucleosomes:
H1, H2A, H2B, H3, H4,
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In a negative inducible operon, transcription is inhibited by a
repressor; this results in a basal transcription rate near zero. However, transcription can be "switched on" by the addition of an inducer protein, which blocks the repressor from binding to the operon.
303
Activators bind to DNA sequences and help "recruit" promoters to start transcription.
They are known to upregulate transcription in positive operons, and in the negative lac operon, the cAMP activator protein (CAP) helps promote the transcription of the genes needed for lactose metabolism. However, for CAP to work, the repressor must have also been removed by an inducer (allolactose in the case of the lac operon).
304
Enhancers are
regulatory DNA sequences found only in eukaryotes. In prokaryotes, the operator serves as the regulatory DNA region instead.
305
Oncogenes
are genes that are involved in cell growth and have the potential to cause cancer. Duplication of oncogenes would result in the upregulation of cell growth cell division, potentially leading to uncontrollable mitosis.
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Cell cycle checkpoint genes are a type of
tumor suppressor gene. They prevent premature cells from undergoing mitosis. For this reason, their amplification would make the cell more resistant to uncontrollable division.
307
Tumor suppressor genes
also known as antioncogenes, regulate cell division. Increased transcription of these genes would reduce the risk of cancer.
308
Inhibitors disable
activators
309
Repressors bind to
operators to reduce transcription
310
Nucleases are enzymes that
cleave nucleic acids. The addition of such enzymes would break down the DNA
311
Proto-oncogene
a gene that regulates normal cell division but that can become a cancer-causing oncogene as a result of mutation or recombination Proto-oncogenes do not necessarily exhibit either a greater or lesser rate of transcription in cancer patients.
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Acetylation __________ gene expression, while methylation __________ it.
promotes, discourages
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Methylation of a gene _______ its proclivity to undergo transcription.
lowers
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Small nucleolar RNAs (or snoRNAs)
are involved in the modification of rRNA. As such, they would be located in the nucleolus, where ribosomes are assembled.
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snRNA, or small nuclear RNA
is found in the nucleus. These molecules aid in the splicing of pre-mRNA.
316
hnRNA is simply an alternative name for
pre-mRNA. As such, not only is this type of nucleic acid found in the nucleus, it also (at least partially, in its exons) codes for peptide products.
317
tRNA molecules are most likely to be found in the
cytoplasm
318
a test cross
a mating between the unknown individual and an individual known to be homozygous recessive (rrll) for the traits in question
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Southern Blot
What blotting technique uses the following for analysis? • DNA
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Northern Blot
Similar technique [to Southern], except that Northern blotting involves radioactive DNA probe binding to sample RNA .
321
Western blot
protein
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eastern blotting
analyze post-translational modification of peptides
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wild type
the traits an animal typically possesses when found in nature. This usually refers to a dominant trait, but not always. If nearly all of the coyotes now have spotted fur, then spotted fur is the wild type.
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In humans, females have two of the same sex chromosome (XX), while males have only one X and one Y. However, the X chromosome is much larger and carries significantly more genes than the Y version. To balance their genetic load with that of males...
one of each female's X chromosomes is inactivated.
325
Virtually all of the cellular machinery and organelles are maternally inherited. Paternal organelles are destroyed during fertilization.
including the mitochondria, golgi apparatus, and lysosomes
326
Mitochondria divide and segregate to daughter cells...
randomly, so it is possible for some gametes to have more mutated mitochondria than others.
327
At the end of meiosis I, cells are already haploid, though they are still paired with their identical sister chromatids.
For this reason, the 46 chromosomes present in a typical somatic cell have already been reduced to 23 by the time that prophase II is reached.
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The nuclear membrane temporarily disintegrates in both
prophase II and mitotic prophase.
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Sister chromatids are pulled apart in
anaphase
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look up mitosis and meiosis vids
khan academy
331
Genes that are sufficiently close together on a chromosome will tend to
stick together, and the versions (alleles) of those genes that are together on a chromosome will tend to be inherited as a pair more often than not. This phenomenon is called genetic linkage. When genes are linked, genetic crosses involving those genes will lead to ratios of gametes (egg and sperm) and offspring types that are not what we'd predict from Mendel's law of independent assortment.
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recombination frequency
So, we can say that a pair of genes with a larger recombination frequency are likely farther apart, while a pair with a smaller recombination frequency are likely closer together. Importantly, recombination frequency "maxes out" at 50\%50%50, percent (which corresponds to genes being unlinked, or assorting independently). That is, 50\%50%50, percent is the largest recombination frequency we'll ever directly measure between genes.
333
Remember the difference between homologous chromosomes and sister chromatids!
Homologous chromosomes are the pairs of non-identical chromosomes that are present in every somatic cell. (For example, you inherit one version of chromosome 2 from your father and one from your mother; these structures are homologous.) These pairings separate during meiosis I, causing the daughter cells generated by this process to be haploid before the start of meiosis II.
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In which of these stages do homologous chromosomes separate into distinct cells?
Anaphase of meiosis I
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synaptonemal complex is a
protein-based linkage that appears during meiosis and connects homologous chromosomes. As these chromosomes must be closely situated to facilitate crossing over, issues could arise involving genetic recombination or synapsis. The synaptonemal complex does not function during mitosis.
336
Genetic drift
is simply the change in allele frequencies due to random processes. Specifically, random chance plays a role in determining which alleles are inherited by offspring from their parents. This can cause some alleles not to be passed down at all, leaving others "fixed" as the only alleles present for that locus. However, genetic drift does not relate to the introduction of new alleles (as mutation does), and cannot increase a population's genetic diversity.
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Sympatric speciation
is that which occurs without a physical barrier. A population that diverges into two separate species in a single cave falls under this form of speciation.
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Parapatric speciation
speciation pattern in which populations speciate while in contact along a common border occurs when segments of two distinct populations overlap. Due to environmental differences, these segments may develop into two species, but individuals in the overlapping areas can typically still interbreed.
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Allopatric speciation
occurs when populations, or parts of the same population, are separated by a physical barrier. Peripatric speciation is a subtype of this concept that occurs specifically when one of the two populations is much smaller than the other.
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Convergent evolution
occurs when entirely separate lineages gradually appear more similar over time. Here, bats, birds, and butterflies are very distantly related, but all evolve to possess wings through different mechanisms. In the end, these species resemble each other despite their genetic differences.
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Parallel evolution
happens when closely related species evolve in a similar way over time. This differs from the question stem, where the three types of organism did not previously resemble each other as strongly.
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Coevolution
requires that two species evolve in response to each other. The question gives no indication that bats evolved in part "because" birds did so, for example.
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Divergent evolution
In this phenomenon, two closely related lineages gradually become more dissimilar.
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Mutualism
is a symbiotic relationship in which both parties benefit. Ex. the ants feed the fungus and the fungus feeds the ants.
345
Commensalism
involves a benefit to only one participating species; the other species is unaffected.
346
Parasitism
occurs when one organism benefits from the relationship at the expense of the other
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Ectosymbiosis
is a specific phenomenon in which one species lives on the surface of another.
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cells walls contain
peptidoglycan
349
Gram-negative bacteria
Bacteria that have a thin peptidoglycan cell wall covered by an outer plasma membrane. They stain very lightly (pink) in Gram stain. Gram-negative bacteria are typically more resistant to antibiotics than Gram-positive bacteria.
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Gram-positive bacteria
Bacteria that have a thick peptido glycan cell wall, and no outer membrane. They stain very darkly (purple) in Gram stain.
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Bacteria replicate by
binary fission
352
transformation
process in which one strain of bacteria is changed by a gene or genes from another strain of bacteria
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viruses with envelopes are ____ sensitive to outside factors
more
354
Virion
a fully formed virus that is able to establish an infection in a host cell
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Prion
misfolded proteins that causes other proteins to become misfolded
356
Viriods
infectious particles found in plants that can silence gene expression by binding to specific RNA sequences
357
lytic pathway
Bacteriophage replication pathway in which a virus immediately replicates in its host and then causes it to lyse, releasing progeny phages (so no integration into host genome)
358
lysogenic pathway
Bacteriophage replication path in which viral DNA becomes integrated into the host's chromosome and then it replicates and lyses releasing progeny phages
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double membrane bound organelles in eukaryotic cells
mitochondria, ER, Golgi body, and nucleus
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anterograde vesicles
vessicles leaving ER with newly formed protein cargo, go to golgi after
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cholesterol in plasma membrane
stabilizes the structure of the plasma membrane when the temperature changes, this reduces fluidity
362
lysosomes
digest proteins (while proteosomes perform functions related to the pentose phosphate pathway and the neutralization of active oxygen species)
363
the inside of the rough ER lumen is similar to...
the extracellular space because proteins are synthesized in the rough ER lumen , and for these proteins to function they must be folded under conditions similar to those in the extracellular environment
364
gap junctions
only allow small molecules through
365
Topoisomerase
Enzyme that functions in DNA replication, helping to relieve strain in the double helix ahead of the replication fork.
366
fluid mosaic model
The mentioned model involves two main aspects: "fluid" and "mosaic." The "fluid" aspect refers to the ability of component molecules to travel laterally within their leaflet of the bilayer, while the word "mosaic" denotes the presence of proteins and other molecules that are scattered in a mosaic within its structure.
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fluidity of a membrane
We are looking for characteristics of a membrane that increase fluidity, especially in cold environments. Unsaturated fatty acids increase fluidity in general, due to the presence of "kinks" in their structure. Cholesterol and similar molecules, which act as a type of buffer system for membrane fluidity, are slightly more complex. Large amounts of cholesterol decrease fluidity at high temperatures but increase it at low temperatures.
368
sodium potassium pump, how many in/out
The Na+/K+ pump helps the cell maintain its membrane potential and creates a concentration gradient. It does this by moving sodium out of the cell and transporting potassium inward. It pumps 3 Na+ ions out of the cell and 2 K+ ions into the cell.
369
the Na+/Ca2+ exchanger must
move calcium ions out of the cell.
370
After a molecule has been engulfed via endocytosis, in what order does it progress through membrane-bound compartments before it is degraded?
Early endosome, late endosome, lysosome
371
Goldi apparatus
The Golgi apparatus functions like a cellular "post office." It receives proteins from the endoplasmic reticulum and packages them into vesicles; these membrane-bound sacs can then travel to specific locations within the cell or to the plasma membrane for excretion. Additionally, lysosomes are formed from vesicles that bud off the Golgi's larger structure. However, note that choice D references enzyme production. Since nearly all enzymes are protein-based, it is the ribosomes - whether free-floating or attached to the rough ER - that synthesize them.
372
Rough ER
synthesis of transmembrane proteins
373
Nucleolus
rRNA production and ribosome assembly
374
lysosomes
facilitate the enzymatic catabolism of protein
375
Peroxisomes
are small membrane-bound organelles that function mainly to break down lipids
376
removal of the ER
Removal of the ER might disrupt the outer leaflet of the nuclear envelope, potentially releasing the contents of the nucleus into the cell and triggering apoptosis.
377
Macrophages must undergo ____ during phagocytosis. If a macrophage cannot engulf bacteria in this
rapid actin reorganization If a macrophage cannot engulf bacteria in this manner, its overall function would be considered very impaired.
378
collagen
is not a cytoskeletal polymer; it is an extracellular fiber that is secreted by certain cell types.
379
Microtubule linking proteins
as their name implies, are used to bind bundles of microtubules together. This is most notably observed in eukaryotic flagella. If these proteins cannot be synthesized, flagella will not work properly, and the function of cells that rely on these structures will be diminished. Of the listed cells, only spermatozoa (sperm cells) possess flagella.
380
Keratin fibers extend across epithelial cells (in the skin, for example) to link adjacent cells via structures called desmosomes.
As a type of intermediate filament, keratin possesses high tensile strength; as such, it can form a network of fibers that distribute mechanical stress among the cells of an epithelial layer. Keratin is therefore the cytoskeletal protein that contributes most to the skin's stretching ability.
381
Collagen contributes heavily to the tensile strength of connective tissue in the skin.
However, it is a fiber in the extracellular matrix, not a component of the cytoskeleton.
382
As some of the longest cells in the body, neurons rely on___to transport neurotransmitter-containing vesicles and macromolecules along their axons.
Type c polymers Therefore, one can expect to find the longest type C polymers in neural cells like those in the cerebral cortex.
383
Cytokinesis involves
a contracting ring of actin microfilaments that pinches the two daughter cells apart. Preventing actin monomers from polymerizing will inhibit the filament reorganization necessary for cytokinesis to occur.
384
Centrosome polarization involves
microtubules Specifically, microtubule extension pushes the centrioles to opposite sides of the cell during mitosis.
385
The formation of the mitotic spindle involves
microtubules, which organize themselves around the centriole.
386
Gram-negative bacteria have
a thinner cell wall, which allows the crystal violet stain to exit the cell. Gram staining first involves exposure to crystal violet stain, which is then fixed with iodine. Gram-positive organisms possess a thick peptidoglycan wall which attaches to crystal violet particles, preventing them from leaving the cell when it is subsequently washed. As a result, these cells stain purple. Gram-negative bacteria, in contrast, possess a thin cell wall that does not fix to the crystal violet stain. Instead, these cells are later stained pink with a counterstain.
387
Gram-positive
thick cell wall - outer membrane absent
388
Which organisms are dependent on the electron transport chain to create ATP?
All obligate aerobes
389
One characteristic of prokaryotic, but not eukaryotic, transcription is that:
mRNA does not undergo post-transcriptional modification.
390
Transduction
a bacteriophage transfers genetic material from one bacterial cell to another during infection.
391
Transformation
occurs when bacteria pick up genetic material from their surroundings.
392
F, or fertility, factor
is a piece of genetic material that codes for the construction of a sex pilus. This bridge allows a bacterium to transfer the factor to another cell, promoting genetic diversity. However, only bacteria with the factor can initiate this transfer, and only to cells that lack it. Typically, the F factor is held outside the main genome in the form of a small plasmid. However, Hfr bacteria represent an interesting phenomenon; in these cells, the F plasmid has become incorporated into the organism's circular chromosome. As these cells do contain the F factor, they can initiate conjugation to F- cells, but they often transfer genomic material along with part or all of the factor.
393
Class I transposons
are known as "copy-and-paste" transposons, as they involve the creation of a new copy of the transposable element. These elements first undergo transcription into RNA using RNA polymerase; as their name implies, they are then reverse transcribed back into DNA and placed in a distinct location elsewhere in the genome.
394
(-)RNA
Negative-sense RNA
395
Prions
tend to induce misfolding and aggregation of endogenous cellular proteins, forming highly stable amyloid fibers. The natural cellular response to the presence of misfolded proteins is the production of heat shock proteins, which help to properly fold the defective protein molecules. The absence of heat shock activity suggests that the cell is not experiencing any problems with protein aggregation, which is one of the hallmarks of prion disease pathology.
396
initiatior tRNA is bound to ____ in eukaryotes and _____ in prokaryotes
methionine-eukaryotes and N-formylmethionine-prokaryotes
397
Conditions of Hardy-Weinberg Equilibrium
1. No mutations 2. Random mating 3. No natural selection 4. Extremely large population size 5. No gene flow 6. no migration in or out of the population
398
Hardy-Weinberg equilibrium equation
p^2 + 2pq + q^2 = 1 p+q=1 p= frequency of dominant allele
399
incomplete penetrance
Clinical symptoms are not always present in individuals who have the disease-causing mutation
400
Expresivity
variations in a phenotype among individuals carrying a particular genotype
401
ANOVA test
-Test of statistical significance when >2 groups.
402
genetic linkage
tendency for genes located close together on the same chromosome to be inherited together, and ones father apart are less likely, but not proportionately so, happens bc crossing over
403
bacteria are
haploid organisms
404
negative control
a repressor prevents transcription by binding to operator ( a sequence upstream of the first protein-coding region) both lac operon and trp operon function based on negative control
405
positive control
an activator stimulates transcription
406
negative inducible operon
the repressor is normally present and the genes are not expressed except under certain conditions
407
negative repressible operon
the genes are usually transcribed,but transcription can be halted by binding of the repressor in appropriate conditions
408
lac operon
-produces genes that use lactose for energy -when high lactose, allolactose get formed from lactose (an isomer) and binds to the repressor, detaching it -if glucose levels low, then cAMP active and binds to CAP which binds to CAP binding sequence and promotes transcription -lac operon is under positive and negative control
409
trp operon
-repressible operon -produces genes necessary to synthesize tryptophan -when tryptophan is absent the repressor does not bind to the operator, and tryptophan synthesis proceeds -when tryptophan is present it binds to the repressor protein and causes it to bind to the operator, thereby inhibiting synthesis -transcription is not repressed by default, but can be induced by environmental conditions, thus is considered a repressible negative operon -
410
endonuclease v exonuclease
Endo-nuclease directly cuts the polynucleotide chain results into two or more fragments whereas exonuclease cuts the nucleotide bases one by one from 3' or 5' end. Endo-nuclease creates single-stranded nick within a chain whereas exonuclease removes the single nucleotides from the end.
411
dideoxy nucleotides are missing which -OH?
3'
412
S phase is
not part of mitosis
413
G2-M checkpoint checks?
that the recently-replicated DNA was copied accurately; if not, mitosis will not occur.
414
Cyclin and Cdks are
crucial cell cycle regulators
415
2 checkpoint in cell cycle
The G1 phase is responsible for protein and organelle production in addition to cell growth. Two major checkpoints mark the cell cycle: one during G1 and the other in G2. In order to pass the G1 checkpoint, the cell must have reached a sufficient size and synthesized enough organelles to move into the S phase. The checkpoint between G2 and mitosis ensures that DNA replication has proceeded accurately.
416
Ectoderm
outermost germ layer; produces sense organs, nerves, and outer layer of skin
417
Endoderm
the inner germ layer that develops into the lining of the digestive and respiratory systems
418
Mesoderm
middle germ layer; develops into muscles, and much of the circulatory, reproductive, and excretory systems
419
in deuterosomes the blastopore becomes the
anus
420
morula
a spherical collection of sixteen cells that is the same size as the original zygote. Further division results in the blastula, a hollow ball of cells. The blastula then develops into the gastrula, which is an invaginated structure containing three germ layers.
421
fibroblasts
cells that produce the fibers comprising connective tissues such as collagen
422
Fibronectin
glycoprotein of the extracellular matrix that binds to membrane-spanning receptor proteins called integrins
423
Cloudin and occludin
proteins that form tight junctions between epithelial cells
424
sympathetic nervous system
stimulates the heart rate and excites the body into activity
425
parasympathetic nervous system
rest and digest, calms you down
426
positioning of neurons in spinal cord
Sensory, or afferent, tracts lie toward the rear (dorsal) side of the spinal cord. In contrast, motor, or efferent, tracts are positioned near the front (ventral) and lateral sides.
427
Depolarization refers to
any phase in which the cell becomes more positive (or less polarized) than its resting value) resting membrane potential for a typical neuron is -70 mV
428
During most of the duration of an action potential, another stimulus, regardless of its strength, cannot cause the neuron to fire again. This is termed the absolute refractory period, and it can be attributed to:
the fact that sodium channels are inactivated.
429
EPSP
Excitatory postsynaptic potential; a slight depolarization of a postsynaptic cell, bringing the membrane potential of that cell closer to the threshold for an action potential.
430
IPSP
Inhibitory postsynaptic potential; a slight hyperpolarization of the postysynaptic cell, moving the membrane potential of that cell further from threshold.
431
inhibitory neurotransmitters
hyperpolarizes (makes more negative) which takes it further from the threshold needed to execute an action potential
432
The adrenal gland can be subdivided into two parts, the adrenal cortex and adrenal medulla, they each produce:
-cortex produces aldosterone and cortisol -medulla secretes epinephrine and norepinephrine.
433
anterior pituitary produces
FSH, LH, ACTH, TSH, prolactin, and growth hormone (GH)
434
the ___________ pituitary does not produce the hormones it secretes
posterior
435
parathyroid glands produce and secrete parathyroid hormone (PTH), which opposes
calcitonin to regulate calcium levels. PTH increases plasma calcium by increasing Ca2+ absorption in the small intestine and extraction of the ion from bone. In other words, high PTH results in high plasma calcium and low bone density. Thus, we can expect that lowered PTH levels would decrease blood calcium levels.
436
the adrenal medulla releases
epinephrine and norepinephrine
437
The adrenal cortex synthesizes and releases
aldosterone and cortisol
438
Oncotic (osmotic) pressure
a force that attempts to pull fluid from the interstitial and intracellular spaces into the capillary, other vessels (arteries etc) are too thick for this to happen
439
myocyte
muscle cell
440
cardiac muscle v smooth muscle
The tissue of the heart itself is composed of cardiac muscle, but blood vessels are coated in smooth muscle
441
speed of blood flowing through capillaries v through other types of blood vessels
The continuity equation is often written as A1v1 = A2v2. This shows us that fluids travel slower through vessels with larger areas. However, we cannot compare the area of a single capillary to that of a single artery or vein, since one artery branches off into many arterioles, which then each branch to form countless capillaries. Thus, it is the combined area of all capillaries - a huge value - that helps us realize that capillaries experience the slowest blood flow of all circulatory vessels. Alternatively, we could simply remember that blood must travel slowly through capillaries to maximize gas and nutrient exchange.
442
Albumin
protein in blood; maintains the proper amount of water in the blood, is the heaviest layer when blood is centrifuged
443
myoglobin v hemoglobin
Myoglobin is found in the muscle, while hemoglobin is found only in the blood. Both molecules use a heme cofactor with an iron center. Myoglobin has a higher oxygen affinity, allowing it to draw oxygen out of the blood effectively. Myoglobin has only one oxygen-binding site. Consequently, it does not bind oxygen cooperatively. Hemoglobin, in contrast, utilizes cooperative binding.
444
2,3-BPG
binds hemoglobin and causes a decrease in oxygen affinity. In adults, this aids in oxygen delivery to the peripheral tissues. Fetal insensitivity to 2,3-BPG permits heightened saturation of fetal hemoglobin. The plasma concentration of 2,3-BPG increases at high altitudes to enables more oxygen to be delivered to the tissues. In other words, 2,3-BPG actually assists oxygen delivery
445
Hemoglobin Binding Curve
4 subunits present in hemoglobin that can be either T or R -state. Cooperative binding leads to a sigmoidal curve.
446
Carbonic anhydrase catalyzes the conversion of water and carbon dioxide to carbonic acid. This process is a crucial part of the maintenance of a buffered blood pH. Which metal cofactor is necessary for carbonic anhydrase to function?
Zinc
447
Hemoglobin's oxygen binding affinity is affected by the pH of its environment and the concentration of carbon dioxide. This relationship is described as the Bohr effect. Which of these conditions would increase the affinity between hemoglobin and oxygen?
The Bohr effect characterizes the inverse relationship between binding affinity and plasma carbon dioxide concentration. An increase in [CO2] generally correlates to an oxygen deficiency, as when an individual exercises. In such conditions, hemoglobin must be able to release oxygen when it reaches the tissues. As a result, when the concentration of carbon dioxide increases, hemoglobin decreases its affinity for oxygen. In contrast, low CO2 concentrations facilitate an increase in binding affinity. Since CO2 in the plasma directly leads to the formation of carbonic acid, low [CO2] correlates to alkaline, or basic, blood.
448
Neutrophils
A type of white blood cell that engulfs invading microbes and contributes to the nonspecific defenses of the body against disease.
449
basophils
A circulating leukocyte that produces histamine.
450
Helper T cells
Helper T cells are critical for activation of the humoral immune response (B cells) and the cellular immune response (T cells). Helper T cells also produce cytokines that fully activate macrophages, allowing them to establish a more acidic phagosomal pH and kill pathogens more effectively.
451
The major histocompatibility complex (MHC)
a set of genes that code for cell surface proteins essential for the acquired immune system to recognize foreign molecules in vertebrates, which in turn determines histocompatibility
452
dendritic cells
specialized white blood cells that patrol the body searching for antigens that produce infections Their main function is to process antigen material and present it on the cell surface to the T cells of the immune system. They act as messengers between the innate and the adaptive immune systems.
453
innate immunity
Immunity that is present before exposure and effective from birth. Responds to a broad range of pathogens.
454
adaptive immunity
the ability to recognize and remember specific antigens and mount an attack on them
455
Nernst equation
Ecell= (RT/nF) (lnQ) used to calculate equilibrium potential, used with neurons
456
hypothalamus vs thalamus
hypothalamus- links the nervous system to the endocrine system via the pituitary gland thalamus-relays sense and motor signals, regulates sleep and alertness
457
1, 6 branching bonds in glycogen are broken by
glycogen debranching enzyme
458
1,4 straight chains of glycogen are broken by
glycogen phosphorylase
459
rate limiting and committed step of glycolysis
Phosphofructokinase-1
460
_______ transports glucose into the cell and is inhibited by high levels of _______
hexokinase, its own produce-G6P
461
Glucokinase
present in the pancreatic beta cells as part of the glucose sensor and is responsive to insulin in the liver, its activity is positively correlated with blood sugar
462
at the peak of action potential
sodium ions are not flowing potassium is flowing out
463
electrical synapses, which operate through gap junctions, are composed of which protein subunit
connexin
464
efferent nerves
motor nerves responsible for reflexes
465
viruses are not
diploid
466
Goal of PCR
make many copies of a DNA sequence
467
genetic bottleneck
temporary dramatic reduction in size of a population or species
468
penetrance vs. expressivity
penetrance- probability of gene being expressed if present, it's either expressed or not expressivity- how much genotype is expressed as phenotype, incomplete dominance, the extent to which penetrance happens
469
peptide hormones are associated with
rapid, short term changes in physiological function
470
Are steroid hormones soluble in the blood stream?
no they require transport hormones to reach their targets (ex. sex-hormone-binding globulin, albumin) -once in the cell they bind with nuclear receptors, the nuclear receptor-hormone complex undergoes conformational change and is translocated to the nucleus where the complex binds to DNA and affects gene transcription
471
peptide v steroid hormones
Peptide: -amino acids are the biochemical precursor -usually large -polar -synthesis: Rough ER->Golgi->vesicles->exocytosis -has intermediate stages (preprohormones, prohormones, hormones) -soluble in blood -membrane-bound receptor -uses secondary messenger signal cascade -fast-onset, short-term -functions as a short term response and as a regulator of other hormones -ex: TSH, oxytocin, insulin, calcitonin Steroid: -cholesterol is the biochemical precursor -small -nonpolar -made in smooth ER -no intermediate stages -insoluble in blood, require a transport protein -uses a nuclear receptor -diffuses through membranes -effects DNA transcription in nucleus -slow onset with longer term effects -regulate 3 S's: Salt, Sugar, and Sex ex. estrogen, testosterone, cortisol, aldosterone
472
Tropic Hormones of Anterior Pituitary
TSH, FSH, LH, ACTH affect the release of other hormones
473
Aldosterone
-"salt-retaining hormone" which promotes the retention of Na+ by the kidneys. na+ retention promotes water retention, which promotes a higher blood volume and pressure -also secretes potassium -adrenal cortex
474
Atrial natriuretic peptide (ANP)
oppostie of aldosterone, is released in response to high blood volume and decreases sodium reabsorption
475
Tyrosine Hormones
All derived from the amino acid tyrosine: can act either like steroid or protein hormones so are their own class dopamine catecholamines (act like proteins): norepinephrine, epinephrine, thyroid hormones (act like steroid hormones): T3, T4
476
Hormones that regulate blood glucose
-insulin-lowers glucose levels -glucagon-increases glucose levels -cortisol-increases glucose levels -epinephrine- increases glucose levels -growth hormone-increases glucose levels
477
hormones that regulate calcium levels
-parathyroid hormone (PTH)-increases calcium levels -calcitonin-decreases calcium levels
478
hormones that have to do with fluid regulation
-aldosterone-increases Na+ reabsorption in DCT, increases fluid levels -ADH/vasopressin (same thing)-increases H2O absorption in collecting duct -Atrial natriuric peptide (ANP)-decreases Na+ reabsorption in DCT, decreases fluid levels
479
hormones having to do with stress
-cortisol-increases glucose, decreases inflammation -epinephrine and norepinephrine-increases glucose, regulates sympathetic nervous system and the fight or flight response
480
hormones that regulate metabolic rate
T3 and T4-increase the basal metabolic rate
481
hormones that regulate reproduction and development
-estrogen-female secondary sex characteristics, menstrual cycle regulation -testosterone-male secondary sex characteristics -progesterone-prepares and maintains uterus for pregnancy -LH-increases estrogen or testosterone -FSH-follicle development, spermatogenesis -hCG-increases progesterone levels -prolactin-milk production -oxytocin-smooth muscle contraction (uterine contractions in labor, milk release in breastfeeding)
482
tropic hormones
-TSH-increases thyroid hormones -adrenocorticotropic hormone (ACTH)-increases adrenal cortex activity and thus corticosteroids -LH-increases estrogen and testosterone levels -FSH-follicle development, spermatogenesis -hCG-increases progesterone levels -GnRH-increases LH and FSH levels -Thyrotropin-releasing hormone (TRH)-increases TSH -Corticotropin-releasing factor (CRF)-increases ACTH levels -Growth hormone-releasing hormone (GHRH)-increases growth hormone levels
483
Hypothalamus hormones
GnRH, GHRH, TRH, CRF, PIF
484
anterior pituitary hormones
FSH, LH, TSH, STH, ACTH, GH, and prolactin Anterior Pituitary Hormones"FLAGTOP" F: Follicle Stimulating Hormone L: Luteinizing Hormone A: ACTH G: Growth Hormone T: Thyroid Stimulating Hormone O: MSH - melanOcyte stimulating hormone P: Prolactin
485
posterior pituitary hormones
ADH (vasopressin) and oxytocin
486
only parathyroid hormone is: parathyroid hormone
A hormone of the parathyroid gland that regulates the metabolism of calcium and phosphorus in the body.
487
thyroid hormones
T3, T4, calcitonin
488
adrenal cortex hormones
aldosterone and cortisol
489
adrenal medulla hormones
catecholamines (epinephrine and norepinephrine)
490
Pancreas hormones
insulin, glucagon, somatostatin (inhibits digestive hormones, slows digestion)
491
reproductive organ hormones
estrogen, testosterone, progesterone, human chorionic gonadotropin (hCG)-Human chorionic gonadotropin (hCG) is a hormone produced by the placenta after implantation.
492
keratin is
an intermediate filament
493
actin and ______ are the same thing
microfilaments
494
negatively charged forms of asparagine and glutamine
asparatate and glutamate
495
a mother's breastmilk transfers this immune protection to the infant:
igG antibodies
496
Gastrulation
the process in which a gastrula develops from a blastula by the inward migration of cells aka the process whereby the inner cell mass is converted into the trilaminar embryonic disk comprised of the three primary germ layers (ectoderm, mesoderm, and endoderm)
497
Ectoderm
outermost germ layer; produces sense organs, nerves, and outer layer of skin
498
Endoderm
innermost germ layer; develops into the linings of the digestive tract and much of the respiratory system
499
Mesoderm
middle germ layer; develops into muscles, and much of the circulatory, reproductive, and excretory systems
500
the normal maturation pathway of ova is...
oogonia (2n)->Primary oocyte (occurs via mitosis, 2n) ->secondary oocyte (completion of meiosis 1, n) -> mature ovum (completion of meiosis 2, this process requires sperm (n)) each month one primary oocyte comes out of its arrest (in prophase 1) and develops into a secondary oocyte, which ruptures from the follicle and is released into the fallopian tube
