Bio/Biochem Flashcards
(191 cards)
1
Q
Chirality of AAs
A
All AAs are chiral (L) except glycine and they all are S except cysteine.
2
Q
Nonpolar, nonaromatic AAs
A
glycine, alanine, valine, leucine, isoleucine, methionine, proline
3
Q
Aromatic AAs
A
Tyrosine, tryptophan, pheynylalanine
4
Q
Polar AAs
A
Serine, threonine, glutamine, asparagine, cysteine
5
Q
Negatively Charged AAs
A
Glutamate and aspartate
6
Q
Positively Charged AAs
A
Lysine, arginine, histadine
7
Q
pI determination of AAs
A
Average of pKa values for each H of the AA
8
Q
Peptide bond formation/breakdown
A
Condensation (dehydration) reaction to form with nucleophilic amino group attacking electrophilic carbonyl; hydrolysis to break
9
Q
Primary structure
A
The AA sequence
10
Q
Secondary Structure
A
local structure stabilized by H-bonding; includes a helices and beta pleated sheets
11
Q
Tertiary Structure
A
3D structure stabilized by hydrophobic interactions, acid base interactions (salt bridges), hydrogen bonding, and disulfide bonds
12
Q
Quaternary structure
A
Interactions between subunits.
13
Q
Denaturation
A
Caused by heating or solutes.
14
Q
Structural Proteins
A
Fibrous; include collagen, elastin, keratin, tubulin, actin
15
Q
Motor Proteins
A
Capable of force generation through conformational change; myosin, kynesin, dynein
16
Q
Binding Proteins
A
Bind a specific substrate, either to sequester it in the body or hold its concentration at a steady state
17
Q
Cell Adhesion Molecules (CAMs)
A
Bind cells to other cells or surfaces, include cadhedrins, integrins, and selectins
18
Q
Antibodies (immunoglobulins Ig)
A
Target a specific antigen which may be a protein in the surface of a pathogen or a toxin
19
Q
Ligases
A
Join two large biomolecules, often of the same type
20
Q
Isomerases
A
Catalyze the interconversion of isomers, including both constitutional and stereoisomers
21
Q
Lyases
A
Catalyze cleavage without the addition of water and without the transfer of electrons; the reverse reaction (synthesis) is usually more biologically important
22
Q
Hydrolases
A
Catalyze cleavage with the addition of water
23
Q
Oxidoreductases
A
Catalyze oxidation reduction reactions that involve electron transfer.
24
Q
Transferases
A
Transfer function groups between molecules
25
Enzyme Mechanisms
Enzymes lower the activation energy of the reaction, thereby increasing the rate (kinetics) without altering the thermodynamics (∆G, ∆H) or the equiibrium
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Competitive Inhibition
Binds to active site, raises Km, no change to Vmax
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Noncompetitive Inhibition
Binds to allosteric site (present regardless of substrate); no change to Km, Vmax lowered
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Mixed inhibtion
Binds to allosteric site, Km increases or decreases, Vmax lowered
29
Uncompetitive Inhibition
Binds to allosteric site (present only when substrate is bound); Km decreases, Vmax lowered
30
Michaelis-Menten Curve
Reaction velocity vs. Substrate concentration; Vmax is asymptote, Km is [S] when v = 1/2 Vmax
31
Lineweaver-Burk Plot
Y intercept is 1/vmax, X intercept i -1/Km; cooperative enzymes show a sigmoidal curve
32
3, 4, 5 carbons sugars
triose, tetrose, pentose
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Aldose
Sugars with aldehydes as their most oxidized group
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Ketose
Sugars with ketones as their most oxidized group
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Chirality of Sugars
If the highest numbered chiral carbon with an OH group is on the right --> D; if left --> L
36
Enantiomers
Differ at all chiral centers
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Diastereomers
Differ at at least one - but not all - chiral centers
38
Epimer
Differ at exactly one chiral center (type of diastereomer)
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Anomer
A type of epimer that differs at the anomeric carbon
40
Anomeric carbon
When a sugar cyclizes, this carbon takes on either alpha or beta conformation and is a new chiral center; the carbon containing the carbonyl in the straight chain form
41
Alpha vs Beta sugars
alpha anomers: have the -OH on the anomeric carbon trans to the free -CH2OH group
beta anomers: have the -OH on the anomeric carbon cis to the free -CH2OH group
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Mutarotation
Process by which one anomer shifts to another with the straight chain form as an intermediate
43
Reactions of monosaccharides
Redox; esterification; glycoside formation (basis for building complex carbohydrates and requires anomeric carbon to link to another sugar)
44
Deoxy sugars
Sugars with an -H replacing and -OH
45
Sucrose
glucose-alpha-1,2-fructose
46
Lactose
galactose-beta-1-4-glucose
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Maltose
glucose-alpha-1,4-glucose
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Cellulose
Main structural component of plant cell walls; main source of fiber in the human diet
49
Starches (amylose and amylopectin)
Main energy storage forms for plants
50
Glycogen
A major energy storage form for animals
51
Nucleoside
Five carbon sugar bound to a nitrogenous base
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Nucleotide
A nucleoside with 1-3 phosphate groups added
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Purines
Adenine and guanine; double-ringed
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Pyrimadines
Cytosine, uracil, and thiamine; single-ringed
55
Differences between Euk/Prok replication
Euk: Nucleotides added by DNA polymerases alpha and delta, RNA primers removed by RNase H, primers replaced by DNA polymerase delta; has telomeres synth by telomerase
Prok: Nucleotides added by DNA polymerase III, RNA primers removed and replaced by DNA polymerase I
56
Nucleosome
When DNA is wound around histones
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Heterochromatin
Dense, transcriptionally silent, DNA
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Euchromatin
Less dense, transcriptionally active DNA
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Genomic Library
Contains large fragments of DNA, including introns; cannot be used to make recombinant proteins or for gene therapy
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cDNA library
Contains smaller fragments of DNA only including the exons of genes expressed by the sample tissue; can be used to make recombinant proteins or for gene therapy
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Start codon
AUG
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Stop codons
UAA, UGA, UAG
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What helps prevent mutations from affecting codons?
Redundancy and wobble
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Nonsense mutations
Premature stop codon
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Missense mutations
Produces a codon that codes for a different AA
66
Frameshift mutations
Result from nucleotide addition or deletion and change the reading frame of the subsequent codons
67
RNA is structurally similar to DNA except:
Ribose instead of deoxyribose, uracil for thiamine, single stranded instead of double stranded
68
Steps in transcription
1) DNA helicase and topoisomerase unwind the double helix
2) RNA pol II binds to the TATA box in the promoter region of the gene (25 bp upstream of first transcribed base)
3) hnRNA is synthesized from antisense strand of DNA
4) 5' cap and poly-A tail added
5) Spliceosome removes introns and ligates exons together
69
Transation Stages
1) initiation
2) elongation
3) termination
4) posttranslational modifications including: folding by chaperones, formation of quaternary structure, cleavage of proteins or signal sequences, and covalent addition of other biomolecules
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Difference between promoters and enhancers (eukaryotes)
Promoters are within 25 bp of the first transcription site, enhancers are farther upstream than 25 bp
71
Osmotic Pressure
The pressure applied to a pure solvent to prevent osmosis; π = iMRT where i is the van't hoff factor
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Passive Transport
Movement of molecules down concentration gradient w/o ATP
1) simple diffusion - small nonpolar molecules do not req. transporters
2) osmosis - the movement of water across selectively permeable membrane
3) facilitated diffusion - uses transport proteins to move impermeable solutes across the cell membrane
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Active Transport
Requires energy in the form of ATP (primary) or an existing favorable gradient (secondary) --> secondary can be symport or antiport
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Endocytosis and Exocytosis
Both methods of engulfing material into cells or releasing material to the exterior of cells, both via the cell membrane
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Pinocytosis and Phagocytosis
The ingestion of liquid and solid, respectively, into the cell from vesicles formed from the cell membrane
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Glycolysis location and yield
Cytoplasm of all cells; 2 ATP per glucose
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Glycolysis key enzymes - describe and star irreversible.
Gluco/hexokinase* - traps glucose
PFK-1* - rate limiting step
PFK-2 - produces F2,6BP which activates PFK-1
G3PDH - produces NADH
3-phosphoglycerate kinase and pyruvate kinase* - perform substrate level phosphorylation
78
What is the fate of the NADH produced in glycolysis?
Oxidized aerobically by the ETC or anaerobically by cytoplasmic lactate dehydrogenase
79
What is the function of pyruvate dehydrogenase? How is it regulated?
Converts pyruvate to acetyl-CoA for Krebs cycle, producing 2 NADH per glucose (one per pyruvate). Stimulated by insulin and inhibited by acetyl CoA.
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Where is the Citric Acid Cycle and what is its purpose?`
Mitochondrial matrix; to oxidize acetyl-CoA to CO2 and generate high-energy electron carriers (NADH and FADH2) and GTP
81
What is the net yield of citric acid cycle per glucose?
6 NADH, 2 FADH2, 2 GTP
82
Where is the ETC and how does it function?
Matrix-facing surface of the inner mitochondrial membrane; NADH donates electrons to the chain, which are passed from one complex to the next via increasing reduction potentials --> O2 is the final acceptor and has the highest reduction potential
83
How does NADH transfer it's electrons to the ETC inside of the inner mitochondrial membrane?
Glycerol-3-phosphate shuttle and malate-aspartate shuttle
84
What is the proton-motive force?
The electrochemical gradient generated by the electron transport chain across the inner mitochondrial membrane; intermembrane space has more protons than the matrix
85
What is chemiosmotic coupling?
How ATP synthase uses energy from the proton gradient to power the unfavorable synthesis of ATP from ADP and Pi.
86
How many ATP per NADH and FADH2
NADH - 2.5
| FADH2 - 1.5
87
Net yield of aerobic metabolism per glucose?
2 (glycolysis) + 2 (citric acid cycle - from GTP) + 25 (NADH) + 3 (FADH2) = 32 if optimal conditions
88
What is glycogenesis?
Glycogen synthesis
89
What two enzymes complete glycogenesis?
Glycogen synthase - created alpha-1,4 glycosidic links between glucose molecules; activated by insulin in the liver and muscles
Branching enzyme - moves a block of oligoglucose from one chain and connects it as a branch using an alpha-1,6 glycosidic link
90
What is glycogenolysis?
The breakdown of glycogen
91
What two enzymes complete glycogenolysis?
Glycogen phosphorylase - removed single glucose 1-phosphate molecules by breaking alpha-1,4 glycosidic links; in liver, activated by glucagon to prevent low blood sugar, in skeletal muscles, activated by epinephrine and AMP to provide glucose for the muscle
Debranching enzyme - moves a block of oligoglucose from one branch and moves it to the chain with an alpha-1,4 glycosidic link
92
What is gluconeogenesis? How are the irreversible reactions bypassed?
De novo synthesis of glucose in the liver (cytoplasm and mitochondria); uses same enzymes as glycolysis in reverse
1) pyruvate kinase bypassed by pyruvate carboxylase and PEP carboxykinase
2) F1,6Bphosphase bypasses PFK-1
3) gluco/hexokinase bypassed by G6phosphatase
93
What is the Pentose Phosphate pathway and where does it occur?
Generates NADPH to rereduce antioxidants and ribose as a base for nucleotides; occurs in the cytoplasm
94
What characterizes the postprandial (fed) state?
Insulin secretion is high and anabolic (synthesis) metabolism prevails
95
What characterizes the postabsorptive (fasting) state?
insulin secretion decreases while glucagon and catecholamine secretion increase
96
What characterizes the starvation state?
Dramatic increases of glucagon and catecholamines; tissues rely on fatty acids
97
How are lipids transported in the blood?
Chylomicrons, VLDL, IDL, LDL, HDL
98
How is cholesterol obtained?
Dietary sources or biosynthesis in the liver by HMG-CoA reductase
99
What fatty acid can humans synthesize?
Palmitic Acid; produced in cytoplasm from acetyl CoA transported out of the mitochondria
100
Where does FA metabolism occur and how is transport achieved?
FAs are oxidized in the mitochondria via beta-oxidation following transport by the carnitine shuttle
101
Why do ketone bodies form during starvation?
Excess acetyl-CoA in the liver
102
What is Ketolysis?
Regenerates acetyl-CoA for use in the liver
103
Where are proteins digested and how are the raw materials used?
In the small intestine by pepsin; carbon skeletons of AAs are used for energy via gluconeogenesis or ketone body formation; amino groups are fed into the urea cycle for secretion
104
What is the liver's function in metabolism?
Maintains blood glucose through glycogenolysis and gluconeogenesis; processes lipids, cholesterol, bile, urea, and toxins
105
What is the adipose tissue's function in metabolism?
stores and releases lipids
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What is resting muscle's use of metabolism?
Conserves carbohydrates as glycogen and uses free fatty acids as fuel
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What is active muscle's use of metabolism?
May use anaerobic metabolism, ox phos, direct phos (creatine phosphate), or fatty acid oxidation
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What is cardiac muscles's use of metabolism?
uses fatty acid oxidation
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What is the brain's use of metabolism?
uses glucose except in prolonged starvation when it can use ketolysis
110
Nucleus
contains genetic material necessary for cell replication
111
Mitochondrion
site of many metabolic processes including pyruvate dehydrogenase, the citric acid cycle, electron transport chain, beta oxidation, gluconeogenesis, urea cycle, and ATP synthesis
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Lysosomes
Membrane-bound structures containing hydrolytic enzymes capable of breaking down many different substrates
113
Rough ER
interconnected membranous structure that contains ribosomes responsible for translation of new proteins destined for insertion into membranes or secretions
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Smooth ER
interconnected membranous structure where lipid synthesis and detoxification occurs
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Golgi apparatus
Membrane-bound sacs where post-translational modification of proteins occurs
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Peroxisomes
Hydrogen peroxide containing organelle responsible for beta oxidation of very long fatty acids
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Fluid Mosaic model
phospholipid bilayer with cholesterol and embedded proteins
exterior - hydrophilic phosphate head groups
interior - hydrophobic fatty acid carbon chains
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Cell Theory
1) all living things composed of cells
2) cells are the most basic unit of living things
3) cells pass info via DNA
4) cells only arise from other cells
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Bacteria by shape
cocci - spherical
bactilli - rod
spirilli - spiral
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Gram + vs Gram - bacteria?
Based on cell wall composition; gram + have peptidoglycan while gram - have smaller amounts of peptidoglycan with lipopolysaccharides
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Binary fission
How prokaryotes divide/reproduce
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Stages of cell cycle
G1 - cell increases in organelles and cytoplasm
S - DNA replication
G2 - same as G1
M - mitosis/division
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Acronym for Mitosis
PMAT
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Meiosis important steps
P1 - two pairs of sister chromatids form tetrads *crossing over can occur
M1 - homologous chromosomes separate
PMAT2 - identical to mitosis except no replication
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When does meiosis occur?
Spermatogenesis and oogenesis
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Four stages of early embryonic development
cleavage - mitotic divisions
implantation - embryo implants during blastula stage
gastrulation - ectoderm, endoderm, and mesoderm form
neurulation - germ layers develop a nervous system
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Ectoderm
Top germ layer and "attract" oderm
| Hair, skin, nails, brain, lens of eye, inner ear
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Mesoderm
Middle germ layer and "muscle"derm
| Muscles, skeleton, circulatory system, gonads, kidneys
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Endoderm
Lower germ layer and "endernal organs"
| Lining of the digestive tract, lungs, liver and pancreas
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Components of osmoreglation
Filtration - at the glomerulus, filtrate passes through
Secretion - of acids, bases, and ions from interstitial fluid to filtrate; maintains pH, [K+], and [waste]
Reabsorption - essential substances and water flow from filtrate to blood; enabled by osmolarity gradient and selective permeability of the walls
131
Action of aldosterone
Stimulated Na+ reabsorption and K+ and H+ secretion, increasing water reabsorption, blood volume, and blood pressure
Secreted from adrenal cortex, regulated by renin-angiotensin-aldosterone system
132
Action of ADH
Increases collecting ducts permeability to water to increase water absorption
Secreted from posterior pituitary with when high [solute] in blood
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Livers roles in homeostasis
1) gluconeogenesis
2) processing of nitrogenous wastes (urea)
3) detoxification of wastes/chemicals/drugs
4) storage of iron and vitamin A
5) synthesis of bile and blood proteins
6) beta oxidation of fatty acids to ketones
7) interconversion of carbohydrates, fats, and amino acids
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Anterior Pituitary Hormones
FSH - stimulates follicle maturation, spermatogenesis
LH - stimulates ovulation; testosterone synthesis
ACTH - stimulates adrenal cortex to make and secrete glucocorticoids
TH - stimulates thyroid to produce thyroid hormones
Prolactin - stimulates milk production and secretion
Endorphins - inhibits perception of pain
GH - stimulates bone and muscle groups/lipolysis
135
Posterior Pituitary Hormones
*produced in hypothalamus, stored in posterior pituitary
Oxytocin - stimulates uterine contractions during labor, milk secretion during lactation
ADH - increases blood volume/pressure by stimulating insertion of aquaporins in the collecting duct of the nephron
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Thyroid Hormones
T3, T4 - stimulates metabolic activity
| Calcitonin - decreases blood calcium
137
Parathyroid Hormone
Increases blood calcium
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Adrenal Cortex Hormones
Glucocorticoids - increase blood glucose level and decrease protein synthesis; anti-inflammatory
Mineralcorticoids - increase water reabsorption in the kidney
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Adrenal Medulla Hormones
Epinephrine, Norepinephrine - Increase blood glucose level and heart rate
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Pancreatic Hormones
Glucagon - Stimulates conversion of glycogen to glucose in the liver, increasing blood glucose
Insulin - Stimulates conversion of glucose to glycogen, lowering blood glucose and increasing glycogen stores
Somatostatin - Suppresses secretion of glucagon and insulin
141
Testosterone
Released from the testes; maintains male secondary sex characteristics
142
Hormones from Ovary/Placenta
Estrogen - Maintains female secondary sex characteristics
| Progesterone - Promotes growth/maintenance of the endometrium
143
Melatonin
Released from the pineal gland; regulates sleep-wake cycles
144
Atrial natriuretic peptide
Released from the heart; involved in osmoregulation and vasodilation
145
Thymosin
Released from the thymus; stimulates T-cell development
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Menstrual Cycle Stages
1) Follicular - FSH causes growth of the follicle
2) Ovulation - LH causes follicle to release egg
3) Luteal - Corpus luteum forms
4) Menstruation - endometrial lining sheds
147
How is the RMP of neurons maintained?
Na/K ATPase pumps 3 Na+ out for 2 K+ in
148
Action Potential
Stimulus acts on the neuron, depolarizing the membrane of the cell body
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Impulse propogation
Depolarization (Na+ rushes into the cell) followed by repolarization (K+ rushes out of the cell) along the axon
150
Action at the synapse
1) At the synaptic terminal, voltage-gated Ca++ channels open sending Ca++ into the cell
2) Vesicles fuse with the synaptic membrane, releasing NTs into the synaptic cleft
3) NTs bind to receptors on the post synaptic membrane, triggering depolarization
151
Neuron channel statuses at different stages of AP
Rest - All gates closed
Depolarization - Na+ gates open
Repolarization - Na+ gates inactivated, K+ gates open
Hyperpolarization - All gates closed
152
What is the sarcomere?
The contractile unit of the fibers in skeletal muscle
| Spans z-line to z-line (mid point of thin actin fibers on either side of myosin fibers)
153
Steps of skeletal muscle contraction
1) Depolarization of neuron leads to action potential
2) Sarcoplasmic reticulum releases Ca++
3) Ca++ binds to troponin on the actin filament
4) Tropomyosin shifts, exposing myosin binding sites
5) Myosin binds, ATPase activity allows myosin to pull thin filaments towards the center of the H zone, and then ATP causes dissociation
6) Ca++ is pumped back into the sarcoplamic reticulum
154
Osteoblast vs Osteoclast
Builds vs. Breaks down bone
155
Reformation (bone)
Inorganic ions are absorbed from the blood for use in bone
156
Degradation (bone)
Inorganic ions are released into the blood
157
Circulatory pathway through the heart
Superior + inferior vena cavae --> right atrium --> tricuspid valve --> right ventricle --> pulmonary artery --> lungs --> pulmonary vein --> left atrium --> bicuspid valve --> left ventricle --> aorta
158
Three portal systems
Blood travels through an additional capillary bed before returning to the heart
Hepatic, Hypophyseal, Renal
159
Fetal Circulation (different parts)
Foramen Ovale - connects right and left atria
Ductus arteriosus - connects pulmonary artery to aorta; shunts blood away from the lungs (along w FO)
Ductus venosus - connects umbilical vein to inferior vena cava, connecting umbilical circulation to central circulation
160
Blood components
Plasma - aqueous mixture of nutrients, gases, wastes, hormones, blood proteins, and salts
RBCs - carry oxygen via hemoglobin
Leukocytes - immune function
Platelets - clotting
161
Oxygen-hemoglobin dissociation + what causes rightward shift
Sigmoidal curve indicative of cooperative binding
- incrs temp
- bohr effect (dcrs pH, incrs PCO2): bc H+ binds allosterically to Hb enhancing release to the tissues and incrs PCO2 leads to incs H+
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Blood buffer equation
CO2 + H2O --> (carbonic anhydrase) --> H2CO3 --> H+ + HCO3-
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Blood clotting
1) Platelets release thromboplastin, which (along with cofactors and vitamin K) converts prothrombin to active thrombin
2) thrombin converts fibrinogen to fibrin, which surrounds blood cells to form a clot
164
Blood Types
A - A antigen, anti-B antibodies
B - B antigen, anti-A antibodies
AB - A, B antigens, no antibodies; universal receiver
O - no antigens, all antibodies; universal donor
+ = yes Rh antigen, no anti-Rh antibody and vice versa
165
Gas exchange in the lungs
1) Deoxy blood enters the pulmonary capillaries that surround the alveoli
2) O2 from inhaled air diffuses down gradient into the capillaries, where it binds to Hb and returns to the heart
3) CO2 from the tissues diffuses from the capillaries to the alveoli and is exhaled
166
Fetal Respiration
Fetal Hb has higher affinity to O2; gas and nutrient exchange occurs across placenta
167
Lipid digestion
1) when chyme is present, duodenum secretes CCK into the blood
2) CCK stimulates secretion of pancreatic enzymes into the bile, and promotes satiety
- bile is made in the liver and emulsifies fat in the small intestine (NOT an enzyme)
- Lipase is an enzyme made in the pancreas that hydrolyzes lipids in the small intestine
168
Carbohydrate Digestion
Salivary amylase - produced by salivary glands in mouth; starch --> maltose
Pancreatic amylase - produced by pancreas, acts in small intestine; starch --> maltose
Maltase - produced by intestinal glands, acts in small intestine; maltose --> 2 glucose
Sucrase - produced by intestinal glands, acts in small intestine; sucrose --> glucose, fructose
Lactase - produced by intestinal glands, acts in small intestine; lactose --> glucose, galactose
169
Protein Digestion
Pepsin - produced by chief cells, acts in stomach; hydrolyzes peptide bonds
Trypsin - produced in pancreas, acts in small intestine; hydrolyzes specific peptide bonds, converts chymotrypsinogen to chymotrypsin
Chymotrypsin - produced in pancreas, acts in small intestine; hydrolyzes specific peptide bonds
Carboxypeptidases A and B - produced in pancreas, acts in small intestine; hydrolyzes terminal peptide bonds at C-terminus
Aminopeptidase - produced in intestinal glands, acts in small intestine; hydrolyzes terminal peptide bonds at N-terminus
Dipeptidase - produced in intestinal glands, acts in small intestine; hydrolyzes pairs of AAs
Enteropeptidase - produced in intestinal glands, acts in small intestine; converts trypsinogen to trypsin
170
Nonspecific Immune Response
Skin, passages lined w cilia, macrophages, inflammatory response, and interferons (proteins that prevent spread of virus)
171
Humoral Immunity
B-lymphocytes - memory cells (remember antigen, speed up secondary response) and plasma cells (make and release antibodies which induce antigen phagocytosis)
172
Cell-Mediated Immunity
T-lymphocytes - cytotoxic T-cells (destroy cells directly), helper T-cells (activate B and T cells and macrophages by secreting lymphokines), and suppressor T-cells (regulate B and T cells to decrease anti-antigen activity)
173
Organization of lymphatic system
1) Lymph vessels meet at the thoracic duct in the upper chest and neck, draining into the left subclavian vein
2) vessels carry lymph (excess interstitial fluid) and lacteals collect fats by absorbing chylomicrons in the small intestine
3) lymph nodes are swellings along the vessels with phagocytic cells (leukocytes); remove foreign particles from the lymph
174
Law of Segregation
Homologous alleles (chromosomes) separate so that each gamete has one copy of each gene
175
Law of Independent Assortment
Alleles of unlinked genes assort independently in meiosis
*for two traits: AaBb parents will produce AB, Ab, aB, and ab gametes and the phenotypic ratio for this cross is 9:3:3:1
176
Probability of genotype that requires multiple events to occur
Product of probability of each event
177
Probability of genotype that can be the result of multiple different events
Sum of probability of each event
178
How can genes be unlinked?
Crossing over during prophase of meiosis I.
179
Determine recombinant frequencies?
How many map units apart are the two genes
180
Autosomal recessive
skips generations
181
Autosomal dominant
appears in every generation
182
X-linked
no male-to-male transmission and more males are affected
183
Hardy Weinberg equilibrium
When populations are stable: no mutations, large population, random mating, no migration, and equal reproductive success
p^2 + 2pq +q^2 = 1; p + q = 1
184
Operon Genes
structural - contains DNA that codes for a protein
promoter - binding site of RNA polymerase
operator - binding site for repressor
185
Inducible vs Repressible Systems
Inducible systems need an inducer for transcription to occur, repressible systems need a corepressor for transcription to stop
186
Virus
Acellular structure of double- or single- stranded DNA or RNA in a protein coat
187
Lytic vs Lysogenic Cycles
Lytic - virus kills host cell
| Lysogenic - virus enters host genome
188
Plasmids
Extragenomic material found in most bacteria; if can be integrated into the genome = episomes
189
Transformation (bacteria)
When bacteria incorporates genetic material from the environment into host cell genome; antibiotic resistance
190
Conjugation
Bacterial mating - two cells form a cytoplasmic bridge (made from sex pili, only on donor males with sex factors) between them allowing for transfer of genetic material (one way from male to female)
191
Transduction
Transfer of genetic information from bacterium to bacterium via infection with bacteriophages
