Biology and Biochemistry Flashcards
1
Q
competitive inhibition
A
binding site: active site
impact on Km: increases
impact on Vmax: none
*can be overcome by increasing the substrate concentration, so Km will increase (more substrate needed to reach 1/2 Vmax)
2
Q
noncompetitive inhibition
A
binding site: allosteric site
impact on Km: no change
*active enzyme still has same affinity for substrate
impact on Vmax: decreases
*less enzyme available to react due to allosteric site
3
Q
mixed inhibition
A
binding site: allosteric site
impact on Km: increases or decreases
impact on Vmax: decreases
4
Q
uncompetitive enzyme
A
binding site: enzyme-substrate complex
impact on Km: decreases
impact on Vmax: decreases
5
Q
catalytic efficiency
A
kcat/Km
6
Q
lower Km means
A
higher enzyme affinity for a substrate
7
Q
order of circulation
A
superior and inferior vena cava right atrium (tricuspid valve) right ventricle pulmonary arteries lungs pulmonary veins left atrium (bicuspid/mitral valve) left ventricle aorta body
8
Q
blood buffer equation
A
CO2 + H2O ⇌ H2CO3 ⇌ H+ + HCO3-
9
Q
veins
A
carry blood low in oxygen to the heart
10
Q
arteries
A
carry oxygen rich blood to body
11
Q
Vmax is limited
A
if all active sites of enzyme are occupied, adding more substrate does not increase the reaction rate
12
Q
prokaryote cell wall (gram positive or gram negative)
A
gram positive –> purple : thick layer of peptidoglycan
gram negative –> pink/red : thin, less peptidoglycan
13
Q
plasmids
A
carry DNA that is no necessary for the survival of prokaryote
14
Q
binary fission
A
asexual reproduction in prokaryotes
15
Q
genetic recombination
A
transformation, transduction, and conjugation
integration DNA into genome
-antibiotic resistance
-virulence factors
16
Q
transformation
A
integration of foreign genetic material into the host genome
gram negative rods
17
Q
conjugation
A
2 cells form a conjugation bridge to transfer genetic material donor male (+) and recipient female (-)
18
Q
transduction
A
virus transfers genetic material from one bacterium to another
ex: bacteriophages
19
Q
viruses
A
DNA or RNA
do not have the ribosomes
must express and replication genetic info within the host cell
20
Q
bacteriophages
A
viruses that target bacteria by injecting their genetic material
21
Q
positive sense
A
genome may be directly translated to functional proteins by ribosomes of host cell (like mRNA)
22
Q
negative sense
A
template
*carry RNA replicase so complementary strand can be synthesized
23
Q
retroviruses
A
single stranded RNA viruses
reverse transcriptase –> synthesizes DNA from SS RNA –> integrated into host genome –> replicated and transcribed
24
Q
lytic life cycle
A
virulent
maximize cell’s functions, no regard for host cell survival
25
lysogenic cycle
viral genes integrated into host genome
26
prion
infectious protein
| causes misfolding of protein
27
viroids
small pathogens with short circular SS RNA
| no protein
28
glucogenic amino acid
all but leucine and lysine
| can be converted into glucose through gluconeogenesis
29
ketogenic amino acids
leucine, lysine, isoleucine, phenylalanine, threonine, tryptophan, tyrosine
converted into acetyl CoA and ketone bodies
30
ketone bodies
transportable forms of acetyl CoA
produced by liver
used by other tissues during prolonged starvation
31
ketolysis
breakdown of ketone bodies
when: during prolonged fast (brain!!)
(pyruvate dehydrogenase is inhibited so glycolysis and glucose uptake decreases to spare essential proteins)
32
acetyl CoA and oxaloacetate form ...
citrate
| when: beginning of citric acid cycle
33
Beta oxidation
reverse of fatty acid synthesis
*oxidizing and releasing molecules of acetyl CoA
each 4 step cycle releases 1 acetyl CoA and reduces NAD+ and FAD
34
importance of acetyl CoA (B oxidation producing it)
- it enters the citric acid cycle in muscle
- in the liver, it stimulates gluconeogenesis by activating pyruvate carboxylase
- use it to synthesize ketone bodies
35
types of enzymes
| LIL' HOT
Lyase
Isomerase
Ligase
Hydrolase
Oxidoreductase
Transferase
36
lyases
cleavage of single molecule into two products
| NO WATER
37
isomerases
rearrangement of bonds
38
ligases
addition or synthesis reactions, requires ATP
39
hydrolase
breaking with water
| phosphatase, cleaves phosphate group
40
oxidoreductase
redox reactions
| "dehydrogenase"
41
transferase
movement of functional group
| kinases: transfer or phosphate
42
cofactors (coenzymes)
bind to active site of enzyme and participate in catalysis of reaction
inorganic molecules or metal ions
(vitamins, NAD+, FAD, coenzyme A)
43
high kcat and low Km
high turnover (substrate ==> products) and high substrate affinity means higher catalytic efficiency
44
kcat
number of substrate molecules "turned over" or converted to product
45
gel electrophoresis
separate macromolecules, like DNA and proteins, by size and charge
DNA molecules are negatively charged and migrate toward anode
larger molecules move less
46
SNOW DROP
| blots
Southern: DNA
Northern: RNA
Western: Protein
47
triaglycerols
- energy storage and insulation
- carbon atoms are more reduced so oxidation yield twice as much energy
- hydrophobic --> do not require water for stability
48
saturated fatty acids
only single bonds, solid at room temp (greater van der Waals forces)
49
unsaturated fatty acids
double bonds --> kinks --> liquid at room temp
50
myelin
insulator --> maintains electrical signal within a neuron
| increases speed of conduction
51
liver
production of bile (stored in gallbladder)
production of urea
synthesis of albumin (bile salts, pigments, cholesterol)
clotting factors
detoxification of chemicals
processing and synthesis of nutrients
52
alveoli
- gas exchange with capillaries
- lungs --> bronchi --> bronchioles --> alveoli
-blood has low partial pressure of oxygen and high partial pressure of carbon dioxide when it reaches alveoli (TRANSFERRED DOWN CONC GRADIENT)
53
capillaries
- single endothelial layer
- diffusion of gases, nutrients, wastes
- allow endocrine signals to arrive at target tissues
54
thyroid hormone
TSH --> thyroid --> T3 and T4 (stimulate metabolic activity)
| calcitonin (decrease blood calcium concentration)
55
hypothalamus
controls pituitary
| negative feedback
56
hypothalamus releases
- GnRH
- GHRH
- TRH
- CRF
anterior pituitary releases
- FSH and LH
- growth hormone
- thyroid stimulating hormone
- ACTH
57
products of anterior pituitary
```
FLAT PEG
(tropic)
FSH
LH
ACTH
TSH
(direct)
Prolactin
Endorphins
GH
```
58
direct hormones example
insulin, prolactin, endorphins, growth hormone
59
tropic hormones
require intermediary
60
peptide amino acids hormones
ex: ADH, insulin
charged, cannot pass through membrane, so bind to extracellular receptor
first messenger --> binds to receptor and signals second messenger (signaling cascade)
RAPID, SHORT LIVED
WATER SOLUBLE
61
second messengers examples
cAMP, IP3, and calcium
62
activation of G protein-coupled receptor
activate or inhibit adenylate cyclase --> increase or decrease cAMP
cAMP binds to intracellular targets like protein kinase A
this phosphorylates transcription factors
63
steroid hormones
can cross cell membrane
intracellular receptor --> conformational change (dimerization)
SLOW, LONG-LIVED
NOT WATER SOLUBLE
64
amino acid derived hormones
2 methods
bind to G protein-coupled receptor --> epinephrine, norepinephrine (FAST)
intracellularly bind (SLOW) --> thyroid hormones
65
functions of proteins involved in muscular contraction:
| myosin, actin, troponin
myosin: motor protein, hydrolyzes ATP
actin: motor activity but does NOT hydrolyze ATP
troponin: chaperone of actin, activity modulated by calcium
66
vector
- bacterial or viral plasmids that can be transferred to host after adding DNA of interest
* too large to be inserted into sequence
* not super precise
67
initiation of skeletal muscle contraction
where: neuromuscular junction
acetylcholine binds to receptors on sarcolemma --> depolarization
action potential travels down sarcolemma to T-tubules
travels down T-tubules to muscles tissues (sarcoplasmic reticulum)
68
heteroplasmy
variation in mitochondrial composition of DNA
| *result of self-replication and cell division by mitochondria
69
transposons
genetic elements that can insert or remove themselves from genome
70
most negative free energy
| *K, reduction potential (E^o)
position reduction potential
| K >1
71
ADH
makes you pee less
| *increases reabsorption of water in collecting duct
72
increased blood volume leads to _____ blood pressure
increased
73
glomerular filtration rate
rate at which kidneys filter blood
| - pressurized blood enters glomerulus
74
osmotic pressure
"pulling" force on water into blood due to presence of solutes
75
hydrostatic pressure
"pushing" force on water out of blood due to presence of more fluid
*larger volumes of fluid = higher hydrostatic pressure
76
in artery, hydrostatic pressure is ______
high
| drives fluids out of capillaries into tissues
77
in vein, hydrostatic pressure is _____
low
| water has been lost
78
aldosterone
acts on distal convoluted tubule and collecting duct
| increases reabsorption of Na+ and water and secretion of K+
79
gluconeogenesis is ______ by glucagon and ______ by insulin
stimulated by glucagon
| inhibited by insulin
80
chaperone proteins
assist in folding of proteins, prevent nonfunctional aggregates from forming
81
what is the role of calcium in myosin-actin binding during muscle contraction?
calcium binds to troponin, which allows tropomyosin to move, allowing myosin and actin to interact
82
how can you reduce the action potential transmission?
increase neuron-firing threshold
| influx of anions (hyperpolarizes neuron)
83
how to measure activity of Na+ K+ ATPase?
rate of ATP hydrolysis
rate of ADP production
change in ion concentration
84
how many Na+ and K+ ions are pumped across membrane, and which direction?
3 Na+ out of the cell
| 2 K+ into the cell
85
how do enzymes alter rate of chemical reactions?
- co-localizing substrates
- altering local pH
- altering substrate shape
86
what is the role of endothelial cells?
they are in direct contact with blood
| gas exchange!
87
action potential steps
1. stimulus causes cell to depolarize toward threshold potential
2. if threshold reached, voltage-gated Na+ channels open and membrane depolarizes
3. at peak, K+ channels open and K+ leaves cell, Na+ channels close
4. membrane becomes hyperpolarized as K+ leaves cell (membrane enters refractory period where it cannot fire)
5. K+ channels close and Na+/K+ pump restores resting potential
88
what is depolarization?
when membrane potential increases
89
what channels open as a result of depolarization?
voltage-gated calcium channels open, influx of calcium leads to release of neurotransmitter
90
GLUT 1
brain and erythrocytes
high affinity for glucose (low Km) --> insulin independent
91
GLUT 2
liver and pancreas
lower affinity for glucose (high Km) --> insulin independent
92
GLUT 3
brain
| high affinity for glucose (low Km) --> insulin independent
93
GLUT 4
muscle, adipose, heart
medium affinity for glucose
INSULIN DEPENDENT
94
NADPH
important for biosynthesis of fatty acids and cholesterol
| electron donor
95
NADH
high-energy carrier
electron acceptor
ETC to indirectly produce ATP
96
tight junctions
prevent solutes from leaking
| restrict passage of solutes
97
reduction potential
likelihood of being reduction
| how much oxidizing agent wants to take electrons
98
for galvanic and electrolytic cells: electrons go from _____ to ______
anode to cathode
99
what is the function of salt bridges in the electrolytic/galvanic cells?
allow counter ions not involved in the reaction to balance out the charges
100
cations move to the
cathode
101
anions move to the
anode
