Biochemistry Flashcards
1
Q
What is the most common intracellular buffer?
A
Protein
2
Q
What is the most common extracellular buffer?
A
Bicarbonate
3
Q
What is a zwitterion?
A
A molecule with one negative and one positive end
4
Q
What is the isoelectric point?
A
The pH at which there is no net charge
5
Q
What is the rate limiting enzyme in glycolysis?
A
PFK-1
6
Q
What is the rate limiting enzyme in gluconeogenesis?
A
Pyruvate carboxylase
7
Q
What is the rate limiting enzyme in the HMP shunt?
A
G-6PD
8
Q
What is the rate limiting enzyme in glycogenesis?
A
Glycogen synthase
9
Q
What is the rate limiting enzyme in glycogenolysis?
A
Glycogen phosphorylase
10
Q
What is the rate limiting enzyme in fatty acid synthesis?
A
AcCoA carboxylase
11
Q
What is the rate limiting enzyme in beta oxidation?
A
CAT-1
12
Q
What is the rate limiting enzyme in cholesterol synthesis?
A
HMG CoA reductase
13
Q
What is the rate limiting enzyme in ketogenosis?
A
HMG CoA synthase
14
Q
What is the rate limiting enzyme in purine synthesis?
A
PRPP synthase
15
Q
What is the rate limiting enzyme in pyrimidine synthesis?
A
Aspartate transcarbamoylase
16
Q
What is the rate limiting enzyme in the TCA cycle?
A
Isocitrate dehydrogenase
17
Q
What is the rate limiting enzyme in the urea cycle?
A
CPS-1
18
Q
What is the rate limiting enzyme in heme synthesis?
A
Delta-ALA synthase
19
Q
What are the catabolic pathways that create energy?
A
ABC
Acetyl CoA production
Beta-oxidation
Citric acid cycle
20
Q
What are the anabolic pathways that store energy?
A
EFGH ER Fatty acid synthesis Glycolysis HMP shunt
21
Q
What are the anabolic and catabolic pathways?
A
HUG
Heme synthesis
Urea cycle
Gluconeogenesis
22
Q
Isomerase
A
Creates an isomer
Glucose fructose
23
Q
Epimerase
A
Creates an epimer
Glucose galactose
24
Q
Mutase
A
Moves side chain from one carbon to another carbon
25
Transferase
Moves side chain from one substrate to another
26
Transaminase
Moves amino group
27
Kinase
Phosphorylates using ATP
28
Phosphorylase
Phosphorylates using Pi
29
Carboxylase
Forms C-C bonds using CO2, ATP, and biotin
30
Synthase
Stacks substrates, does not use ATP
31
Synthetase
Stacks substrates, uses ATP
32
Phosphatase
Breaks phosphate bond
33
Hydrolase
Breaks a bond with water
34
Lyase
Cuts C-C bond with ATP
35
Dehydrogenase
Removes H with a cofactor (NADH, FADH2)
36
Thio-
Breaks sulfur bonds
37
Diffusion
From high to low concentration
38
Active transport
Goes against concentration gradient
39
Zero-order kinetics
Metabolism independent of concentration
40
First-order kinetics
Constant drug percentage metabolism over time, depends on concentration
41
Efficacy
Max effect regardless of dose
| Lower with non-competitive antagonist
42
What affects efficacy?
Vmax
43
Potency
Amount of drug needed to produce effect
| Lower with competitive antagonist
44
What affects potency?
Km
45
Km
Concentration of drug that binds 50% of receptors
46
EC50
Concentration of drug that produces 50% of maximal response
47
Competitive inhibition
Fights for active site
No change in Vmax
Decreases potency
48
Non-competitive inhibition
Binds regulatory site
No change in Km
Decreases Vmax
Decreases efficacy
49
Endothermic reaction
Consumes heat
| Feels cold
50
Exothermic reaction
Gives off heat
| Feels warm
51
Peak level
4 hours after dose
| Too high —> decreases dose
52
Trough level
2 hours before dose
Too high —> give less often
(Unless q6 hour drug, then 1 hour before dose)
53
t1/2
Half-life
| Time it takes for the body to use half of the drug ingested
54
von Gierke
G-6Pase deficiency
Hypoglycemia
Hepatosplenomegaly
55
Pompe’s
Cardiac alpha-1,4-glucosidase deficiency
| DIE early
56
Cori’s
Debranching enzyme deficiency
| SHORT branches of glycogen
57
Anderson’s
Branching enzyme deficiency
| LONG chains of glycogen
58
McArdle’s
Muscle phosphorylase deficiency
| Muscle cramps with exercise
59
Essential fructosuria
Fructokinase deficiency
Excrete fructose
Still have hexokinase so benign (incidental finding usually)
60
Fructosemia
“Fructose intolerance”
Aldolase B deficiency
Liver damage
61
Galactokinase deficiency causes?
Cataracts
62
Galactosemia causes?
Cataracts
Mental retardation
Liver damage
63
What does the citrate shuttle do?
Fatty acid transport out of the mitochondria
64
What does the carnitine shuttle do?
Fatty acid transport into the mitochondria
65
What lysosomal diseases have a cherry-red macula? (2)
Tay-Sachs
| Neimann-Pick
66
What lysosomal diseases have a gargoyle face? (2)
Gaucher’s
| Hurler’s
67
Tay-Sachs
Hexosaminidase A deficiency
Blindness
Incoordination
Dementia
68
Sandhoff’s
Hexosaminidase A/B deficiency
69
Gaucher’s
Glucocerebrosidase deficiency
Wrinkled tissue macrophage
Bone pain
70
Neimann-Pick
Sphingomyelinase deficiency
| Zebra bodies
71
Fabry’s
Alpha-galactosidase deficiency
Corneal clouding
Attacks baby’s kidneys
X-linked
72
Krabbe’s
Beta-galactosidase deficiency
| Globoid bodies
73
Metachromatic leukodystrophy
Arylsulfatase deficiency
| Childhood multiple sclerosis
74
Hunter’s
Iduronidase deficiency
| Milder form
75
Hurler’s
Iduronidase deficiency
| Worse form
76
Lesch-Nyhan
HGPRT deficiency
Gout
Neuropathy
Self-mutilation
Hypoxanthine guanine phosphoribosyltransferase
(Herbert self mutilates)
77
What do white diaper crystals suggest?
Excess orotic acid
78
What does biotin act as a cofactor for by donating CO2?
Carboxylation
79
What does THF donate methyl groups for?
Nucleotides
80
What does SAM donate methyl groups for?
All other reactions (not nucleotides - THF)
81
What is the difference between heterochromatin and euchromatin?
Heterochromatin — tightly coiled
| Euchromatin — loose (10nm fibers), active
82
What are the purines?
Pur As Gold
83
What are the pyrimidines?
C, U, T
84
Silent mutation
Changes leave the same amino acid
85
Point mutation
Changes one base
86
Transition (mutation)
Changes one purine to another purine or pyrimidine to pyrimidine
87
Transversion (mutation)
Changes one purine to a pyrimidine or vice versa
88
Frameshift mutation
Insert or delete 1-2 bases
89
Missense mutation
Mistaken amino acid substitution
90
Nonsense mutation
Early stop codon
91
Southern blot detects?
DNA
92
Northern blot detects?
RNA
93
Western blot detects?
Protein
94
What are the essential amino acids?
```
PVT TIM HALL
Phe - phenylalanine
Val - valine
Trp - tryptophan
Thr - threonine
Iso - isoleucine
Met - methionine
His - histidine
Arg - arginine
Lys - lysine
Leu - leucine
```
Tyrosine becomes essential if phenylalanine is deficient
95
Essential fatty acids
Linolenic
| Linoleic
96
Acidic amino acids
Asp
| Glu
97
Basic amino acids
Lys
| Arg
98
Sulfur containing amino acids
Cys
| Met
99
O-bond amino acids
Ser
Thr
Tyr
100
N-bond amino acids
Asn
| Gln
101
Branched chain amino acids
Can’t LIV without them
Leu
Iso
Val
102
Aromatic amino acids
Phe
Tyr
Trp
103
Smallest amino acid
Glycine
104
Ketogenic amino acids
Lys
| Leu
105
Glucogenic + ketogenic amino acids
```
PITT
Phe
Iso
Thr
Trp
```
106
Glucogenic amino acids
All the rest
107
Trypsin cuts?
Tryp to LA
Lys
Arg
108
Beta ME cuts?
Sulfur containing amino acids
Cys
Met
109
Chymotrypsin cuts?
Phe
Tyr
Trp
110
Carboxypeptidase cuts?
Left(!) of any amino acid on the carboxy terminal (right terminal)
111
Aminopeptidase cuts?
Right of N terminus
112
CNBr cuts?
Right of Met
113
Mercaptoethanol cuts?
Right of Cys, Met
114
Elastase cuts?
Right of Gly, Ala, Ser
115
What amino acids does acid hydrolysis denature?
Asn
| Gln
116
What amino acid turns yellow on Nurhydrin reaction?
Proline
| All others turn purple
117
What does alpha1-antitrypsin do?
Inhibits trypsin from getting loose
118
PKU
No phenylalanine to tyrosine via phenylalanine hydroxylase
Nutrasweet sensitivity
Mental retardation
Pale, blonde hair, blue eyes
Musty odor
Phenylalanine restrictive diet
Tyrosine becomes essential
119
Albinism
Tyrosinase deficiency
| No Tyr to melanin
120
Maple syrup urine disease
Defective metabolism of branched amino acids (Leu, Iso, Val)
Amino acids leak out into urine
Tastes sweet, smells like burnt sugar
121
Homocysteinuria
```
No homocysteine to cysteine
COLA stones
Cysteine
Ornithine
Lysine
Arginine
```
122
Pellagra
Niacin deficiency
```
4D’s
Dermatitis
Diarrhea
Dementia
Death
```
123
Hartnup’s
No Trp to make niacin or serotonin
Presents like pellagra
Can mimic corn rich diet
124
What causes anterior leg bowing?
Neonatal syphilis
125
What causes lateral leg bowing?
Rickets
126
What are the names of the B vitamins?
“The Rich Never Lie about Panning Pyrite Filled Creeks”
```
Vitamin B1: Thiamine
Vitamin B2: Riboflavin
Vitamin B3: Niacin
Vitamin B4: Lipoic acid
Vitamin B5: Pantothenic acid
Vitamin B6: Pyridoxine
Vitamin B9: Folate
Vitamin B12: Cobalamin
```
127
Vitamin A
Night vision
CSF production
PTH
128
Vitamin B1 Thiamine
Cofactor for dehydrogenases and transketolase
129
Vitamin B2 Riboflavin
FAD cofactor
130
Vitamin B3 Niacin
NAD cofactor
131
Vitamin B4 Lipoic Acid
Glycolysis
| No known disease
132
Vitamin B5 Pantothenic Acid
Part of AcetylCoA
| No known disease
133
Vitamin B6 Pyridoxine
Cofactor for transaminases
| Myelin integrity
134
Vitamin B9 Folate
Nuclear division
135
Vitamin B12 Cobalamin
Cofactor for HMT and MMM
136
Vitamin C
Collagen synthesis
137
Vitamin D
Mineralization of bones and teeth
138
Vitamin K
Clotting factors
| 10, 9, 7, 2, C
139
Biotin
Cofactor for carboxylation
140
Calcium
Neuronal function
Atrial depolarization
Smooth muscle contractility
141
Copper
Collagen synthesis
142
Iron Fe2+
Hemoglobin function
| Electron transport
143
Bronze pigmentation
Iron deposit in skin
144
Bronze cirrhosis
Iron deposit in liver
145
Bronze diabetes
Iron deposit in pancreas
146
Hemosiderosis
Iron overload in bone marrow
147
Hemochromatosis
Iron deposit in organs
148
Magnesium
PTH
| Cofactor for kinases
149
Zinc
Taste buds
Hair
Sperm function
150
Chromium
Insulin function
151
Molebdenum
Purine breakdown (xanthine oxidase)
152
Manganese
Glycolysis
153
Selenium
Heart function
Deficiency —> dilated cardiomyopathy
Smells like garlic
154
Tin
Hair growth
155
Fluoride
Teeth and bone growth
| Excess blocks enolase in glycolysis (low energy state)
156
Iodine
Endocrine function
157
Kwashiorkor
```
Malabsorption
Big belly (ascites)
Protein deficiency
```
158
Marasmus
Starvation
Skinny
Calorie deficient
159
Where does the Pre label send stuff?
Rough Endoplasmic Reticulum
160
Where does the Pro label send stuff?
Golgi
161
Where does the Mannose-6-Phosphate send stuff?
Lysosome
162
Where does the N-terminal sequence send stuff?
Mitochondria
163
What are the 4 types of collagen?
SCAB
1: Skin, bone
2: Connective tissue, aqueous humor
3: Arteries
4: Basement membrane
164
How does scleroderma present?
Tight skin
165
How does Ehlers Danlos present?
Hyperstretchable skin
166
How does Marfan’s present?
```
Hyperextensible joints
Arachnodactyly
Wing span longer than height
Aortic root dilation
Aortic aneurysm
Mitral valve prolapse
Dislocated lens from bottom —> look up to Mars
```
167
How does Homocysteinuria present?
Marfan’s in child
| Dislocated lens from top —> looking down at child
168
How does Minky’s kinky hair syndrome present?
Hair looks like copper wire
| Copper deficiency
169
How does Scurvy present?
Bleeding gums and hair follicles
170
How does Takasayu’s arteritis present?
Asian women with very weak pulse
| Granulomatous aortitis
171
How does Osteogenesis Imperfecta present?
Blue sclera
Shattered bones
Not child abuse
