Biology/Biochem Flashcards
(132 cards)
1
Q
Competitive Inhibitor
A
Binds to active site. Creates less enzymes available to be activated.
Vmax stays the same, Km increases
2
Q
Noncompetitive Inhibitor
A
Binds to the allosteric site. The substrate can still bind to the active site. Can occur with or without enzyme-substrate complex.
Vmax decreases, Km stays the same
3
Q
Uncompetitive Inhibitor
A
The inhibitor binds to the allosteric site of enzyme-substrate complex.
Vmax decreases, Km decreases
4
Q
Vmax
A
When all available enzymes have become enzyme-substrate complex.
5
Q
Km
A
Substrate concentration at 1/2 Vmax
6
Q
Innate Immunity
A
A nonspecific defense mechanism that comes into play immediately or within hours of an antigen’s appearance.
Always active
7
Q
Components of the innate Immunity system
A
Anatomic Barriers
Leukocytes
Complement system
Cytokines/Interferons
Inflammation
8
Q
Neutrophils
A
Most abundant type of leukocyte. first responder to aninfection. Phagocytoses bacteria
9
Q
Natural killer cells
A
Responds to cells infected by viruses and tumors to kill them and prevent the spread of an infection
10
Q
Monocytes
A
Travel throughout the body to differentiate into dendritic cells or macrophages
11
Q
Dendritic cells
A
Serve as the bridge between adaptive and immune responses by presenting antigens to T cells
12
Q
Macrophages
A
Large cells that phagocytose many pathogens and particles that don’t belong. Is sometimes compared to a garbage truck
13
Q
Eosinophils
A
Target parasitic infections
14
Q
Basophils
A
Involved in allergic responses
15
Q
Adaptive Immunity
A
Adapts to the environment and learns to recognize and eliminate specific pathogens
16
Q
Maturation Process of B cells
A
- B cells are produced in the bone marrow. Considered naive B cells because they haven’t encountered antigens yet
- B cells migrate from bone marrow to lymphatic tissues
- Random recombination occurs. certain parts of B cell nucleic DNA are randomly altered and will cause a wide variety of antigen receptors to be expressed (Each B cell will only express one receptor)
- B cell with newly expressed antigen receptor never finds matching antigen. Gets destroyed
- B cell finds matching antigen and undergoes clonal selection
- Specific B cell with matching antigen proliferates through the process of clonal selection. Takes about a week to proliferate
- B cells become activated after clonal selection
- Specific B cells become plasma cells and secrete massive amounts of antibodies into the blood stream
- Become memory B cells which lie dormant in lymph nodes until antigens are present again.
17
Q
Humoral immunity (B cells)
A
Main function of B cells is to secrete antibodies in response to an antigen
18
Q
Cell-Mediated Immunity (T cells)
A
Activation of phagocytes, antigen-specific cytotoxic T lymphocytes
19
Q
Positive Selection of T cells
A
T cells fail to respond appropriately to antigens and are eliminated
20
Q
Negative Selection of T cells
A
T cells react too harshly against the healthy cells of the body and are elminated
21
Q
Helper T cells
A
Communicates with other cells of the immune system. Activates B cells and Killer T cells and others to increase the immune response. Also known as CD4+ cells
22
Q
Killer T cells
A
Responds to MHC 1. Injects target cell with substances that induce apoptosis. When this happens killer T cells become activated and proliferate. Also known as CD8+ cells
23
Q
Natural Killer cells
A
Responds similar to killer T cells but will destroy any cells missing MHC 1. Also known as NK cells
24
Q
MHC 1
A
Present on all nucleated cells. Presents proteins from inside the cell to the surface. Recognized by Killer T cells
25
MHC 2
Only presents on certain cells known as antigen-presenting cells. Antigen-presenting cells phagocytize particles and present fragments on their surface through the MHC 2. Antigens recognized by CD4+ cells
26
Calcitonin
Stimulates osteoblasts to build bone. This decreases blood calcium.
27
Parathyroid Hormone (PTH)
Secreted by the parathyroid glands. Stimulates osteoclasts to consume bone, which increases blood calcium.
28
Hardy-Weinberg Equilibirum Criteria
1. No mutation (change) in the DNA sequence
2. No migration (moving into or out of a population)
3. A very large population size
4. Random mating
5. No natural selection
29
Cell cycle Phases
30
G1 Phase
Considered the growing phase. The cell grows and accumulates the building blocks of chromosomal DNA and the associated proteins as well as sufficient energy to complete the task of replicating each chromosome in the nucleus. Cells also increase in size and produce organelles.
31
S phase
Called the synthesis phase, the process takes the longest because of the complexity of the duplicated genetic material. This is where DNA replication occurs.
32
G2 phase
Cells replenish their energy stores and synthesize proteins necessary for chromosome manipulation. The cell has double the DNA and again increases in size. Some cell organelles are duplicated and the cytoskeleton is dismantled to provide resources for the mitotic phase.
33
M phase
The phase where cell enters mitotic phase.
34
G0 phase
Cells that are in G0 phase are not actively preparing to divide. Basically in an inactive stage. Cells that are usually in this stage are mature cardiac muscle and nerve cells.
35
Promoter
The sequence of DNA that defines where transcription of a gene by RNA polymerase begins. It also defines the direction of transcription and indicates which DNA strand will be transcribed
36
Transcription Factor
Protein that controls the rate of transcription of genetic information from DNA to messenger RNA by binding to a specific DNA sequence (Promotor)
37
Spliceosome
Complex of proteins along with tertiary RNAs that are responsible for the cleavage of the primary RNA transcript during the splicing reaction
38
Mast cells
Immune cells in lungs covered with antibodies. Release inflammatory chemicals upon antigen binding to promote immune response. Responsible for respiratory allergic reactions due to reactions with things like pollen and molds.
39
Lysozyme
Enzyme able to attack petidoglycan walls of gram positive bacteria. Found in nasal cavity, tears, and saliva
40
Bicarbonate Buffer System
Mechanism where respiratory system controls blood pH via controlling carbondioxide concentrations. Less CO2 in blood = More Basic = Body responds with slower breathing to retain CO2. More CO2 in blood = More Acidic = Body increases breathing rate to remove CO2. Hyperventilation decreases CO2 levels in blood, making blood more basic. Body responds with trying to slow breathing rate.
41
Surfactant
Detergeny covering alveoli to reduce surface tension and prevent alveolus from collapsing on itself. Premature babies do not have surfactant.
42
Portal Systems
Transport systems where blood traveling through these systems goes through two capillary beds in series before returning to the heart. The three portal systems are the Hepatic (Gut -\> liver), hypophyseal (Hyopthalamus -\> anterior pituitary), and renal (glomerulus -\> vasa recta).
43
Bohr Effect
Shifting of oxyhemoglobin curve to the right. Can be due to decreased pH and increasing the H+ concentration in the blood. H+ binds to hemoglobin allosterically and reduces affinity for oxygen. This allows more oxygen to be delivered to tissues. Decreased pH can be caused by increased CO2 and lactic acid in blood. Right shift of curve can also be caused by increased temperature, and 2,3-bisphosphoglycerate (2,3-BPG) in
44
Fetal Hemoglobin
(HbF) has higher affinity for oxygen than adult hemoglobin (HbA) in order to pull oxygen from mother's hemoglobin and onto fetal hemoglobin. Results in left shifted oxyhemoglobin dissociation curve
45
Islets of Langerhans
Pancreatic bundles of cells that release hormones. Include alpha, beta, and delta cells, which release glucagon, insulin, and somatostatin respectively.
46
Lipase
Enzyle in saliva that catalyzes the hydrolysis of lipids.
47
Gastric Glands
Dominant glands in the Fundus and Body. Stimulated by the Vagus Nerve of the Parasympathetic Nervous System. Contain three main cell types: Mucous Cells, Chief Cells, and Parietal Cells.
48
Stomach Anatomy
Consists of the Fundus (top), Body (middle), Pylorus (bottom), and Antrum (exit). Lesser curvature is the inside curve, Greater Curvature is the outside curve. Rugae is the internal, folded lining of the stomach.
49
Mucous Cells
Produce bicarbonate-rich mucous that protects the muscular walls of the stomach from the harshly acidic and proteolytic environment.
50
Chief Cells
Secrete pepsinogen in the stomach, the inactivated form of pepsin.
51
Parietal Cells
Secrete hydrochloric acid into the stomach to lower the pH and cleave pepsinogen into pepsin. Low pH also helps kill most harmful bacteria and denature proteins and break down some intramolecular bonds that hold food together. Parietal cells also secrete intrinsic factor.
52
Pepsin
Enzyme produced from pepsinogen being cleaved by hydrogen ions in the stomach. Cleaves peptide bonds near aromatic amino acids, resulting in short, peptide fragments. Uniquely most active at low pH.
53
Pyloric Glands
Dominant glands in the Antrum and Pylorus sections of the stomach. Contain G-cells that secrete gastrin.
54
G-Cells
Cells in the pyloric glands of the stomach that secrete Gastrin
55
Gastrin
Peptide Hormone that induces the parietal cells in the stomach to secrete more HCl and also signals the stomach to contract. Secreted by G-cells
56
Brush Border Enzymes
Enzymes present on the inside surface of cells lining the duodenum that are released in the presence of chyme. These enymes break down dimers and trimers of biomolecules into absorbable monomers. Include disaccharidases and peptidases
57
Lack of Digestive Enzyme
Intestines can't cleave disaccharaide for digestion. This increases osmolarity and pulls water into the intestines to form diarrhea. Bacteria in the small intestine are able to break down disaccharides, but result in methane gas as a biproduct, resulting in farts.
58
Pancreatic Enzymes
Secreated by Acinar Cells. Pancreatic Amylase: Digests carbohydrates. Trypsinogen: Activated by Enteropeptidase (produced in Duodenum) to form trypsin, which then activates chymotrypsinogen. Procarboxypeptidases A and B to protein digestion. Pacreatic Lipase: Breaks down fats into free fatty acids and glycerol
59
Liver
- Regulates blood sugar via glyogenesis, glycogenolysis, gluconeogenesis, and the storage and release of fats. - Converts Ammonia (waste product of amino acid metabolism) into Urea - Detoxifies chemicals such as drugs and alcohol - Produces Bile - Synthesizes albumin and clotting factors
60
Gallbladder
Stores and concentrates bile. CCK stimulates the gallbladder to contract and push bile into the billiary tree, which merges with the pancreatic duct before entering the duodenum via the duodenal papillae. Gallbladder stones made of cholesterol or bilirubin can cause inflammation of the gallbladder and blockage of both the biliary tree and pancreatic ducts.
61
Dump the HUNK
Major waste products excreted in urine are H+, Urea, NH3, and K+.
62
Langerhans cells
Special macrophages that reside within the stratum spinosum of the epidermis. Capable of presenting antigens to T-cells to activate the immune system.
63
Renal Bicarbonate Buffer System
When pH is too high, kidneys can selectively excrete more bicarbonate and reabsorb more H+. When pH is too low, kidneys exctrete more H+ and reabsorb more bicarbonate.
64
SDS page
Denatures proteins and gives them a negative uniform charge. Separated based on size alone. Small move further than large. Positively charged anode. SDS is a strong detergent making the overall charge of polypeptides neglible.
65
Native page
Analyzes folded proteins based on their charge, mass and shape
66
Isoelectric focusing
Electrophoresis technique that separates proteins based on their isoelectric point. The isoelectric point is when a protein has a 0 net charge at certain pH.
67
Pk values to know
* C-terminus = 3.5
* Asp = 3.9
* Glu = 4.1
* His = 6.0
* Cys = 8.4
* N- terminus = 9.0
* Tyr = 10.5
* Lys = 10.5
* Arg = 12.5
Nitrogen will be (+) when protonated, (0) otherwise
Oxygen will be (-) when deprotonated, (0) otherwise
Nitrogen is always positive _unless_ the pH is higher than it's pka. Oxygen is always negative if the pH is higher than it's pka.
Don't Express Hate. Create Your Kindness Right.
68
Michaelis Menten equation
69
Lineweaver burke equation
70
Heterochromatin
Tightly packed form of DNA.
71
Euchromatin
Loose chromatin structure and active for transcription
72
DNA Methylation
the biological process by which methyl groups are added to the DNA molecule. Can change the activity of DNA segment without changing the sequence. When located in a gene promoter, DNA methylation typically acts to repress gene transcription.
73
Microglia
Immune cells found in the nervous system. Glial cells that function as macrophages in the CNS
74
Astrocytes
Star-shaped glial cells that have a number of functions including support of the blood-brain barrier, provision of nutrients to neurons, repair to nervous tissue following injury and facilitation of neurotransmission
75
Satellite Cells
Also known as muscle stem cells. Precursors to skeletal muscle cells.
76
Glial Cells
Cells in the CNS and the PNS that do not produce electrical impulses. They maintain hemostasis, form myelin in the PNS and provide support and protection for neurons.
77
Steroid Hormone
nonpolar and can pass through cell membranes. Enter the nucleus and directly affect the cell at the transcription level
78
Peptide hormones
Polar, which makes it difficult for them to pass through cell membranes. They attach to a receptor on the outside of the membrane.
79
Action potential
80
Antibody structure
81
Ribosome subunit differences
List out multiples of ten 30 - 80 so you get 30,40,50,60,70,80
First two numbers are small subunits, middle two are the large, and last two are the totals. Remember that eukaryotes have the bigger subunit in each category. Then circle the biggest or smallest in each pair to get the corresponding parts of the eukaryotic or prokaryotic ribosomes.
82
Where is glucose broken down?
Liver. Liver also regulates the breakdown of glucose.
83
Muscles
84
Breathing information to know
85
Muscle structure
86
Follicle-Stimulating Hormone (FSH)
Promotes sperm production, stimulates ovaries to produce estrogen
87
Luteinizing Hormone (LH)
Stimulates ovulation in women and testosterone production in men
88
Adrenocorticotrophic hormone (ACTH)
Stimulates the production of cortisol a stress hormone. Helps maintain blood pressure and blood sugar levels.
89
Thyroid-stimulating Hormone (TSH)
Stimulates the thyroid gland which regulates metabolism, energy and the nervous system
90
Prolactin
Causes breast milk to be produced after childbirth. Also affects hormones that control the ovaries and testes, which can affect menstrual periods, sexual functions and fertility
91
Growth Hormone (GH)
Helps maintain healthy muscles and bones and manage fat distribution.
92
Antidiuretic Hormone (ADH)
Increased water permeability of the kidney’s collecting duct and distal convoluted tubule by inducing translocation of aquaporin water channels in the kidney nephron collecting duct plasma membrane. This increases water reabsorption in distal convoluted tubules and collecting ducts of the nephron, producing concentrated urine.
Also called vasopressin
93
Aldosterone
Water and sodium reabsorption in distal convoluted tubules and collecting ducts of the nephron, producing concentrated urine.
94
Female ovulation cycle
95
Histone Acetylation
Acetyl group is transferred from Acetal CoA. Increases gene expression by making the histones looser.
96
Methylation
Acts to silence gene expression
97
Ploidy
How many copies of each chromosome a cell has
98
Lipid-Soluble Vitamins
Vitamins A, D, E and K
99
Water-Soluble Vitamins
Vitamins B and C
100
Single Crossover vs double crossover
A double-crossover event is one in which chromosomal arms of homologous chromosomes cross over in two different places along the arm. This results in a section in the middle of each chromosome being exchanged.
Crossover events occur only during meiosis, not during mitosis.
101
Analogous Structures
Analogous structures are those structures that evolved independently to carry out the same function.
Examples would be, wring of a bee and wing of a bird
102
Homologous structure
have a similar evolutionary history, arising from the same source, even if they now have different functions.
An example would include, human arm vs batwing
103
Pshosphodiester bond
The linkage between the 3' carbon atom of one sugar molecule and the 5' carbon atom of another.
nucleotide monomers in a DNA polymer are connected by strong electromagnetic attractions called phosphodiester bonds.
104
Disulfide bonds
Aid on the connection of proteins alongside peptide bonds. this happens between Cysteine R groups.
105
Nucleotides
106
Nuclear localization Sequence
The sequence of amino acids on proteins that allow them to pass through the nuclear membrane into the nucleus.
107
Signal Sequence
Sequence of amino acids that allows proteins to enter the rough ER and secretory pathway
108
Ubiquitination
Targets a protein for degradation by a proteasome
109
Centrosome
Microtubule - organizing centers. Provides structure for the cell. Also regulates cell cycle progression
110
Kinetochore
The complex of proteins associated with the centromere of a chromosome during cell division, to which the microtubules of the spindle attach
111
Oligodendrocytes
type of large glial cell found in the _central nervous system._ Oligodendrocytes produce the myelin sheath insulating neuronal axons
112
Schwann Cells
are the main glial cells of the _peripheral nervous system_ which wrap around axons of motor and sensory neurons to form the myelin sheath.
113
DNA helicase
works at the replication fork to unwind the helix (unzips DNA)
114
Topoisomerase (includes DNA gyrase)
bind to the separated strands of DNA to keep them from reannealing
115
Primase
creates short RNA primer that is temporarily attached for DNA polymerase to extend from
116
DNA polymerase
follows the replication fork, working to add new nucleotides in 5′ → 3′ direction; proofreads and removes incorrect nucleotides
117
DNA ligase
helps to anneal strands; joins Okazaki fragments
118
Telomerase
lengthens telomeres of linear eukaryotic DNA
119
Secondary Active transport
Secondary active transport uses the energy stored in these gradients to move other substances against their own gradients. Requires cotransporters.
When they move in the same direction, the protein that transports them is called a symporter, while if they move in opposite directions, the protein is called an antiporter.
120
Primary Active transport
Moves things against it's gradient by utilizing ATP.
121
Palindromic sequence
meaning that both strands of DNA will have the same sequence when read 5′ to 3′
Only recognized by four base and eight base sequences.
122
Imprinted Gene
imprinted genes is basically you express one allele in a parent specific way. Meaning that before development, you get 2 alleles from parents for 1 gene. Now one of these allele is methylated, so it is off before you even develop. Hence every cell in your body will express the nonmethylated allele for that gene, hence parent specific.
Example:
Gene X has 2 alelles A and B. So you get allele A from mom, and allele B from dad. But Dad's is methylated to turned off it will never transcribe. So the only allele that is expressed is allele A which is maternal. So you will have paternal imprinting and maternal expressivity. becuz any cell in your body will only express 1 allele.
123
Operon
Genetic regulatory system. Allows protein synthesis to be controlled coordinately in response to the needs of the cell. Typically consists of a group of structural genes that code for enzymes involved in a metabolic pathway. These genes are located contiguously on a stretch of DNA and are under the control of **ONE** promotor. A **single** unit of mRNA is transcribed from the operon and is subsequently translated into separate proteins
124
How does the role of calcium in skeletal and cardiac muscle contraction differ from its function in smooth muscle?
Skeletal and cardiac muscle require calcium to bind to troponin, exposing the myosin binding site.
Smooth muscle contains no troponin, but still relies on calcium for a signaling cascade that promotes contraction.
125
Sarcomere structure
Thin filaments are composed of actin, tropomyosin, and troponin.
Thick filaments are composed of myosin.
126
Briefly describe the process that triggers calcium release from the sarcoplasmic reticulum.
1. Acetylcholine is released from an adjacent motor neuron and binds to receptors on the muscle cell membrane.
2. Ion channels open, causing a large influx of sodium ions and a depolarization of the cell.
3. Calcium release channels in the SR membrane are activated and open; Ca2+ flows down its gradient into the sarcoplasm.
127
How do Ca2+ ions facilitate actin-myosin binding?
Each calcium ion binds to troponin, causing tropomyosin to change its shape. This frees the myosin binding site on the relevant actin molecule.
When calcium is not present, tropomyosin is bound to actin in a position that blocks the myosin binding site. For contraction to occur, this site must be open for the head of a myosin molecule to attach.
128
Sarcomere contraction
129
Henry's Law
Concentration of a dissolved gas = Henry's law constant x Partial pressure of the gas
C=kP
130
Two aspects to consider for vaccine production
Immunogenicity and toxicity.
131
Lineweaver burke plots of inhibitors
Last graph is only for noncompetitive, not mixed.
132
difference between Mixed vs noncompetiive lineweaver burke plot
