problem set 9 Flashcards
1
Q
anticoagulant
A
- aspirin
- large doses of vitamin E
- Coumadin
2
Q
what is the anticoagulant found in small quantities in the blood
A
heparin
3
Q
what is the formation of a clot within a blood vessel
A
thrombsis
4
Q
what is it called if the clot breaks loose and moves elsewhere
A
embolism
5
Q
Prothrombin, fibrinogen, and pepsinogen are examples of
A
zymogen
proenzyme
6
Q
it is an anti-coagulant because it complexes Ca2+, which is needed for blood clotting
A
oxalate
citrate
7
Q
what is the inactive enzyme that is the precursor to the peptidase found in the stomach
A
pepsinogen
8
Q
any metal that is required for enzyme activity is called
A
cofactor
9
Q
specific area on the enzyme where the chemical reaction takes place
A
catalytic site
10
Q
specific area on the enzyme where the substrate binds
A
contact site
11
Q
what is the cofactors plus the protein part called
A
holoenzyme
12
Q
what is the cofactor that is organic but not a protein called
A
coenzyme
13
Q
what peptidase has an optimum pH range near 2
A
pepsin
14
Q
what peptidase is found in the small intestine
A
trypsin
15
Q
what is the inactive protein part (without cofactors) of an enzyme called
A
Apoenzyme
16
Q
what is the largest protein found in blood plasma, its function is blood coagulation
A
fibrinogen
17
Q
different forms of an enzyme that catalyze the same reaction in different organs and tissues of the body is called
A
isoenzyme
18
Q
what vitamin is needed for the synthesis of collagen
A
vitamin C
19
Q
if a blood test taken in the emergency room indicates a high level of LDH and CK enzymes, what could be the cause
A
heart attack
20
Q
Thiamine: coenzyme
A
TPP
21
Q
Riboflavin: coenzyme
A
FAD
22
Q
Niacin: coenzyme
A
NAD
23
Q
Folic Acid: coenzyme
A
THF
24
Q
Pantothenic acid:coenzyme
A
Coenzyme
25
TRUE about general zymogens
1. they usually have their catalytic site blocked by several amino acids
2. several blood clotting enzymes are synthesized as zymogens
26
FALSE about general zymogens
1. catalytic activity
2. usually smaller than active enzyme
3. important for the enzymes needed for carbohydrate metabolism
4. they are sometimes called apoenzymes
27
TRUE plasma proteins
1. they are mainly made in the liver
| 2. serum albumins help maintain osmotic pressure
28
FALSE plasma proteins
1. in times of protein deprivation they will be metabolized before muscle protein
2. there are only four plasma proteins
29
enzymes are held together by...
1. hydrogen bonds
| 2. salt bridges
30
what happens to the rate of an enzyme catalyzed reaction as substrate concentration is raised beyond the saturation point
(enzyme concentration remains constant)
remains the same
31
NOT peptidases
a. pepsin
b. plasmin
c. amylase
d. trypsin
e. thrombin
c. amylase
| e. thrombin
32
TRUE concerning trypsinogen and trypsin
a. trypsin is a protein while trypsinogen is not
b. trypsin is larger protein than trypsinogen
c. trypsin has catalytic ability while trypsinogen does not
d. both have catalytic ability but not for the same substrate
c. trypsin has catalytic ability while trypsinogen does not
33
if an enzyme's turn over rate is very high, it is
very efficient
34
which is found in blood plasma but not in blood serum
fibrinogen
35
calcium ions are needed for __ to be converted into ___
prothrombin --> thrombin
36
what compound causes the conversion of fibrinogen to fibrin
thrombin
37
what is the actual blood clot
fibrin
38
what destroys the blood clot after it is no longer needed
plasmin
39
what is the inactive precursor of thrombin
prothrombin
40
what two things are necessary for the precursor (prothrombin) to be converted to thrombin
1. calcium ions
| 2. thromboplastin
41
enzyme (given to patient after a heart attack) which is used to convert plasminogen to plasmin
streptokinase
42
where would you find covalent bonding
1. disulfide bonds
2. irreversible inhibition
3. peptide bond
4. amide bond
43
why can enzymes be used in diagnostic medicine
1. normally, blood plasma contains very small amounts of enzymes
2. the same enzyme might have slight structural differences depending upon what type of tissue it is in
3. tissue damage can cause enzymes to leak into the blood
4. computerized assay procedures can measure very small quantities of enzymes
44
TRUE concerning enzymes vs. hormones
1. all enzymes are proteins, while some hormones are proteins
2. low concentrations of either can have a dramatic effect
3. hormones can be made in a gland and travel through the blood stream
4. enzymes are used in the cells where they are made
45
factors affecting the activity of all enzymes
1. pH
2. temperature
3. substrate saturation
4. genetic control to increase the concentration of the enzyme
46
catalytically active
holoenzyme
47
TRUE pepsin and pepsinogen
pepsin has catalytic ability while pepsinogen does not
48
part of the enzyme most likely to be deactivated by temperature
apoenzyme
49
what compounds react with hyrolase enzymes in the body
1. fat
2. polysaccharides
3. corn oils
4. tetrapeptide
5. ethyl acetate
50
true of noncompetitive inhibitors
a. Mercury poisoning is an example
b. inhibitor has a different binding site than the substrate
c. binding the inhibitor alters the 3-D shape of the enzyme
d. allosteric enzymes inhibitors are examples
51
lactose
substrate
52
maltase
enzyme
53
maleate isomerase
enzyme
54
alanine
substrate
55
urease
enzyme
56
tyrosine synthetase
enzyme
57
glutamic acid
substrate
58
Allosteric enzymes TRUE
a. they are affected by regulator molecules, which can be inhibitors or activators
b. usually 2 or more subunits, with one unit having the active site, and the other having a regulatory site
c. can be reversed by adding more substrate
d. some allosteric enzymes have several different sites for different regulator molecules
59
false allosteric enzymes
1. allosteric enzymes can cause build up of metabolic products
60
true competitive inhibitors
a. inhibitors resembles the substrate
b. can be reversed by adding more substrate
c. an example is ethanol as an antidote for methanol poisoning
d. sulfa drugs are an example
61
false competitive inhibitors
1. binds at different site than the substrate
| 2. allosteric enzyme inhibitors are an example
62
what type of enzyme would be synthezied first as a zymogen
1. protein digesting enzymes
| 2. blood clotting enzymes
63
what causes permanent enzyme denaturing
a. very high temperatures
| b. large pH changes
64
TRUE acetylcholine
1. contains ester linkage
2. deficiency in the brain is involved in Alzheimer
3. it is a neurotransmitter
4. a molecule that blocks its receptor site can be used as a muscle relaxant
65
TRUE nerve gas
1. it forms a permanent covalent bond with an amino acid at the active site
2. it can cause convulsions and death
3. it affects the enzyme acetylcholine esterase
66
can be reversed by adding an excess of the substrate
competitive
67
which usually forms covalent bonds with the enzyme
irreversible
68
inhibitors look like the substrate
competitive
69
lead poisoning destroys the salt bridges of many enzymes, but it can be removed with EDTA
--lead poisoning is what kind of inhibitor
non-competitive
70
inhibitor binds to enzyme at different site than substrate, but it can be removed
non-competitive
71
nerve gas permanently binds to serine in the active sites
irreversible
72
antifreeze (ethylene glycol) is oxidized in the liver to oxalic acid, which is toxic. The treatment of antifreeze poisoning is intravenous solution of ethanol. what kind of inhibitor is ethanol to the liver enzyme
competitive
73
olive oil to glycerol & 3 fatty acids
hydrolases
74
cis 2-pentene to trans 2-pentene
isomerases
75
glucose-6-phosphate & ADP to glucose & ATP
transferases
76
isocitrate dehydrogenase
oxidoreductases
77
petidases
hydrolases
78
phosphoglucomutase
isomerases
79
glucose-6-phosphate to fructose-6-phosphate
isomerases
80
oxaloacetate & acetyl-CoA to citric acid
ligases
81
transfers an amino group from aspartic acid
transferases
82
hydrolyzes sucrose
hydrolases
83
removes CO2 from pyruvic acid
lyases
84
citric acid sythetase
ligases
85
oxidizes succinic acid
oxidoreductases
86
phosphoglycerate kinase
transferases
87
glutamic-pyruvic transaminase
transferases
88
lactose to glucose and galactose
hydrolases
89
pyruvate decarboxylase
lyases
90
amylose to glucose
hydrolases
91
removes 2H from an alcohol
oxidoreductases
