Biochemical Foundations Flashcards
(98 cards)
1
Q
What is the Michaelis Menten Equation?
A
V0 = (Vmax[S])/(Km + [S])
2
Q
What is Km equal to?
A
Km = [S] when V0 = 1/2 Vmax
3
Q
What is Kcat?
A
Kcat = Vmax/[E]t
4
Q
What is Catalytic Efficiency?
A
Cat. Eff. = Kcat/Km
5
Q
What are the Positively and Negatively charged Amino Acids? (List their abbreviations as well)
A
Positive: Arginine (Arg, R), Lysine (Lys, K), Histidine (His, H)
Negative: Aspartic Acid (Asp, D), Glutamic Acid (Glu, E)
6
Q
What are the Polar Uncharged Amino Acids and their abbreviations?
A
Serine (Ser, S), Threonine (Thr, T), Asparagine (Asn, N), Glutamine (Gln, Q), Cysteine (Cys, C)
7
Q
What are the Hydrophobic Amino Acids and abbreviations?
A
Proline (Pro, P), Glycine (Gly, G), Alanine (Ala, A), Valine (Val, V), Methionine (Met, M), Isoleucine (Ile, I), Leucine (Leu, L)
8
Q
What are the Aromatic AAs and their abbreviations?
A
Phenylalanine (Phe, F), Tyrosine (Tyr, Y), Tryptophan (Trp, W)
9
Q
Which two DNA base pairs are Pyrimidines?
A
Thymine and Cytosine
10
Q
What is a Competitive Inhibitor
A
A molecule that binds to the active site of an enzyme inhibiting enzyme activity
11
Q
What is a Noncompetitive Inhibitor
A
A molecule that binds to the enzyme at a site separate from the active site and does not inhibit enzyme-substrate binding but does inhibit enzyme activity
12
Q
What is an Uncompetitive Inhibitor
A
A molecule that binds to the Enzyme-Substrate complex and inhibits the formation of the product
13
Q
How does Competitive Inhibition affect MM kinetics?
A
Unchanged Vmax, increased Km
14
Q
How does Noncompetitve Inhibition affect MM kinetics?
A
Reduced Vmax, unchanged Km
15
Q
How does Uncompetitve Inhibition affect MM kinetics?
A
Reduced Vmax, reduced Km
16
Q
On a Lineweaver-Burk plot, what are the key things to remember?
A
-1/Km = x-intercept
1/Vmax = y-intercept
Km/Vmax = slope
17
Q
What is the difference between SDS-Page electrophoresis and Native electrophoresis?
A
SDS: Proteins are covered in SDS and separated by their molecular weight.
Native: Proteins are separated by their conformation and charge.
18
Q
What do reducing agents do to proteins?
A
They break disulfide bonds to ensure fully denatured and subunit-separated proteins.
19
Q
On a Thin Layer Chromatography (TLC), which compounds move the farthest up the stationary phase?
A
The less polar the substance, the farther it travels up the stationary phase.
20
Q
What changes the shape of the enzyme in the induced-fit model?
A
The substrate
21
Q
What are the organizational levels of DNA?
A
Chromosomes, Chromatin, Nucleosomes
22
Q
How do you activate or repress Chromatin?
A
Histone acetylation uncoils the Chromatin and is called Euchromatin. Deacetylated Chromatin condenses and is called Heterochromatin.
23
Q
What does Methylation do to gene expression?
A
Methylation silences the genes
24
Q
What do inducers and repressors do to gene expression?
A
Repressors inhibit gene expression and Inducers inhibit repressors
25
Which two sections for gene expression can be located far away from the gene itself?
Enhancers and Silencers
26
What kind of mechanisms can introns have?
Introns can act as transcription promoters, enhance gene expression, and allow the production of mRNA variants.
Introns by nature also have incision sites.
27
What is the basic structure of a steroid?
4 rings. 3 are 6-carbon rings and one is 5 carbon.
28
What is the function of the proximal convoluted tubule in the kidney?
To reabsorb water and solutes like sodium
29
What is the function of the distal convoluted tubule in the kidney?
To reabsorb sodium and chloride
30
What is the function of the cortical portion of the collecting duct in the kidney?
Regulates water and electrolyte balance by secreting sodium and responding to antidiuretic hormone
31
What is the function of the medullary portion of the collecting duct?
Reabsorb water and urea, influencing the composition of urine
32
What is the resting concentrations of Na and K in nerve cells?
Sodium is higher outside the cell and Potassium is higher inside
33
What do transcription factors bind to?
Promoters or enhancers on the DNA
34
What kind of molecules can directly pass through cell membranes?
Hydrophobic molecules
35
What is the function and how of the glomerulus of the mammalian kidney?
It filters the blood using blood osmotic pressure, blood pressure, and capsular pressure
36
What are the steps of the Krebs Cycle?
(Parenthesis indicate enzymes)
Acetyl CoA (Citrate synthase) to Citrate (Aconitase)to Isocitrate (Isocitrate dehydrogenase) to a-Ketoglutarate (a-ketoglutarate dehydrogenase) to Succinyl CoA (Succinyl-CoA synthase) to Succinate (succinate dehydrogenase)
to Fumarate (Fumarase) to Malate (Malate dehydrogenase) to Oxaloacetate.
37
What are the products of the Krebs cycle?
3 NADH, 1 FADH2, 1 ATP, 2 CO2
38
What does insulin do in the liver?
Increases the uptake of glucose, decreasing gluconeogenesis and promotes glycogen synthesis
39
What are the hormones released by the pituitary gland and what do they do?
Growth hormone- regulates growth
Thyroid stimulating hormone (TSH)- activates thyroid
Prolactin- controls breastmilk production
Adrenocorticotrophic hormone (ACTH)- tells adrenal gland to make hormones
Follicle stimulating hormone (FSH)- involved in reproductive system
Luteinizing hormone- involved in reproduction system.
40
How does semiconservative DNA replication work?
DNA replication in which the parent strands are separated and each receive a new strand added to them.
41
What important hormones does the Hypothalamus release?
Dopamine: Feel good/pituitary stop prolactin
Oxytocin: Birthing/lactation assistance and feel good
Vasopressin: ADH; water/urine controller and blood pressure
Somatostatin: Inhibits release of pituitary hormones
42
What does the parathyroid gland do?
Releases Parathyroid hormone which increases blood calcium levels.
43
What hormones does the Thyroid make?
Thyroid hormones (t3, t4): increases metabolism
Calcitonin: reduces blood calcium levels (opposes parathyroid hormone)
44
What hormones does the parathyroid do?
Secrets parathyroid hormone which increases blood calcium levels (opposes calcitonin)
45
What hormones does the adrenal cortex release?
Cortisol: Stress, waking cycle
Aldosterone: ADH; regulates blood pressure and sodium content
46
What hormones does the adrenal medulla release?
Epinephrine: panic response (smooth muscle contractions, metabolism speed up, airway and eyeball stimulation)
Norepinephrine: Focuses on blood pressure and is released at low levels constantly
47
What organelle contains hydrolytic enzymes used to break down things?
Lysosomes and Peroxisomes
48
What does Ubiquitination do?
It marks a protein for breakdown
49
What is Western Blotting and what is it used for?
It combines protein electrophoresis and antibody binding to identify proteins. This is done after SDS-PAGE
50
What is Southern Blotting and what is it used for?
It is used to detect specific DNA sequences. This is done after agarose gel electrophoresis by transferring DNA to a membrane with a radioactive DNA probe.
51
What is Northern Blotting and what is it used for?
It is used to detect specific RNA sequences. This is done after gel electrophoresis by transferring RNA to a membrane with a radioactive probe
52
What does Vasopressin do in the kidneys?
It regulates the insertion of aquaporins into the apical membranes of the epithelial cells in the Collecting duct
53
What is the difference between Schwann cells and Oligodendrocytes?
Schwann cells: Primary myelin-producing cells in the peripheral nervous system
Oligodendrocytes: Primary myelin-producing cells in the central nervous system
54
What do Microglia do?
Mediate the immune response within the CNS
55
What is the Endoplasmic Reticulum?
Branch off of the nucleus. Rough ER has ribosomes and makes proteins for secretion, plasma membrane, or remains in ER, Golgi, or Lysosomes. Smooth ER synthesizes lipids, steroids, Carbs, and aids in detox.
56
What does the Golgi Apparatus do?
Modifies, sorts, sends proteins and synthesizes macromolecules for secretion
57
How much ATP is made in aerobic/anaerobic respiration?
Aerobic: 32
Anaerobic: 2
58
What tissues are made from the Endoderm, Mesoderm, and Ectoderm?
Endoderm: GI tract, Lungs, Liver, Pancreas
Mesoderm: Muscles, Bones, Kidneys, Reproductive organs
Ectoderm: Skin, Nervous system
59
What is a centrosome?
Organelle that serves as the primary microtubule organizing center
60
What is a Kinetochore?
Proteins positioned at the centromere of a chromosome
61
What are the 2 common receptor types with hormones?
Primary Messengers: Hormone binding directly affects transcription/translation. (Can cross cell membrane)
Secondary Messengers: Hormone binding sets off chain reactions of secondary messengers within the cell(s)
62
What does Angiotensin 2 do?
Vasoconstriction, Sodium reabsorption, Stimulates ADH and Aldosterone
63
What is Glycolysis and the Citric Acid Cycle?
Glycolysis processes Glucose down to Pyruvate in the cytosol
CA Cycle processes Acetyl-CoA in a cycle in the mitochondria. This produces NADH and FADH2 to drive the Oxidative Phosphorylation
64
What is a defining characteristic of Restriction Sites?
They are palindromic and specifically recognized
65
What are the names of the 4 complexes and the coenzyme in the Electron Transport Chain?
I: Ubiquinone Oxidoreductase
II: Succinate Dehydrogenase
Coenzyme Q is known as Ubiquinone is in between and carries electrons
III: Cytochrome C Reductase
IV: Cytochrome C Oxidase
66
What is Complex V in the ETC?
ATP synthase
67
What does Reverse Transcriptase do?
A protein that turns RNA into double-stranded DNA
68
What makes a double bond in the Z or E configuration?
Z places the highest priority bonds on the same side, E places them on opposite sides
69
What is a Hz?
Hz = 1/s
70
What is a buffer's buffering capacity?
+- 1 pH unit
71
What is an Amp?
Flow of charge per unit time
A = C/S
72
Where does fatty acid oxidation take place?
The mitochondria
73
What is the order of sites the Amino Acids go through in a ribosome?
A - Amino acid
P- Peptide
E- Exit
74
What does PCR measure?
It measures levels of DNA
75
Which Amino Acids can be phosphorylated in Eukaryotes?
Serine
Threonine
Tyrosine
76
What does adding phosphate groups do to the isoelectric points of molecules?
Decreases them due to Phosphate being negatively charged
77
What do Tight junctions do?
They are intercellular junctions that prevent the movement of solutes within the space between adjacent cells.
78
What kind of intercellular connection between endothelial cells forms the blood brain barrier?
Tight Junctions
79
What is the difference between Desmosomes and Gap junctions?
Desmosome: intercellular junctions that function as anchors to form strong sheets of cells.
Gap Junctions: intercellular junctions that provide cytoplasmic channels between adjacent cells.
80
What polarity does membrane potential have?
Negative
81
What is the difference between extrinsic and external motivation?
Extrinsic: Extrinsic motivation refers to any motivation that results from incentives to perform a behavior that are not inherent to the behavior itself.
External: External motivation is described as social pressure, which is an example of extrinsic motivation.
82
What is the "Glass Escalator"?
The idea that men who pursue occupations that have high proportions of women (such as teaching or nursing) will quickly ascend the career ladder with promotions.
83
What do Cytochrome P450 enzymes do?
They are membrane-bound hemoproteins that detoxicate xenobiotics, cellular metabolism, and homeostasis.
84
How do transcription factors work?
They bind to specific regions of DNA and either activate or repress RNA polymerase
85
What is a carboxyl group?
R-COOH
86
What are the sizes of Human and Bacterial ribosomes?
Human: 40s + 60s to a total 80s
Bacterial: 30s + 50s to a total 70s
87
What is the Carnitine Shuttle?
A pathway that takes long-chain fatty acids and transports them across the mitochondrial membranes by attaching CoA groups to them
88
What is the range of charge in a nerve cell?
-40 to -90 mV
89
What are the steps in an action potential?
1- Depolarization: + charged ions flow into cell bringing charge closer to 0 and eventually + charged.
2- Repolarization: the cell goes back towards being negatively charged
3- Hyperpolarization: The cell becomes more negative than its resting membrane potential.
90
What are the differences between B cells, Cytotoxic T cells, and Helper T cells? (Lymphocytes)
Helper T cells: recruits Cyt. T cells and B cells and macrophages
Cyt. T cells: Kill infected cells and tumor cells
B cells: produces antibodies
91
What is an Oncogene and what is a Tumor suppressor gene?
Oncogene: promotes progression through cell cycle and/or decreases apoptosis.
TSG: promotes cell cycle arrest, apoptosis, and autophagy
92
What is Lyonization?
The inactivation of one of the female X chromosomes
93
What is Flow Cytometry?
The labelling of cells with fluorescent antibodies that specifically bind to a receptor. The cells pass through a laser that fluoresce the cells.
94
What is Anterograde and Retrograde trafficking?
Anterograde: Moving to the cell surface
Retrograde: Moving to the inside of the cell
95
What are some characteristics of peptide and steroid hormones?
Peptide: binds to surface receptors that triggers a signaling cascade. Generally don't enter cell.
Steroid: Diffuses through cell walls, binds to receptors, then enters the nucleus and influences gene expression
96
What order does the blood filter in a nephron?
Glomerulus - Bowman's Capsule - Proximal conv. tubule - Loop of Henle - Distal conv. tubule - collecting duct
97
What is a portal blood vessel?
A vessel that originates from a capillary bed and leads to Another capillary bed without going through the heart
98
What is Ghrelin?
Hunger hormone made in the enteroendocrine cells of the GI tract. It increases when hungry and lowers after mealtimes.
