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 w/ 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
G6PD
8
Q
What is the rate limiting enzyme in glycogenesis?
A
Glycogen synthase
9
Q
What is the rate-limiting enzyme in ß-oxidation?
A
CAT-1
10
Q
What is the rate-limiting enzyme in cholesterol synthesis?
A
HMG-CoA reductase
11
Q
What is the rate-limiting enzyme in ketogenesis?
A
HMG-CoA synthase
12
Q
What is the rate-limiting enzyme in purine synthesis?
A
PRPP synthase
13
Q
What is the rate-limiting enzyme in pyrimidine synthesis?
A
Asp transcarbamylase
14
Q
What is the rate-limiting enzyme in TCA cycle?
A
Isocitrate dehydrogenase
15
Q
What is the rate-limiting enzyme in urea cycle?
A
CPS-1
16
Q
What is the rate-limiting enzyme in Heme synthesis?
A
d-ALA synthase
17
Q
What are the catabolic pathways that create energy?
A
ABC
- acetyl CoA production
- ß-oxidation
- citric acid cycle
18
Q
What are the anabolic pathways that store energy?
A
EFGH
- ER
- Fatty acid synthesis
- Glycolysis
- HMP shunt
19
Q
What are the pathways that are both anabolic & catabolic?
A
HUG
- Heme synthesis
- Urea cycle
- Gluconeogenesis
20
Q
What does an isomerase do?
A
Creates an isomer
21
Q
What does an epimerase do?
A
Creates an epimer, which differs around 1 chiral carbon
22
Q
What does a mutase do?
A
Moves side chain from one carbon to another (intrachain)
23
Q
What does a transferase do?
A
Moves sidechain from one substrate to another (interchain)
24
Q
What does a kinase do?
A
Phosphorylates, using ATP
25
What does a phosphorylase do?
Phosphorylates, using inorganic phosphate
26
What does a carboxylase do?
Forms C-C bonds (w/ ATP and biotin), using CO2
27
What does a synthase do?
Consumes 2 substrates equally
28
What does a synthetase do?
Consumes 2 substrates, uses ATP
29
What does a phosphatase do?
Breaks phosphate bond
30
What does a hydrolase do?
Breaks a bond with water
31
What does a lyase do?
Cuts C-C bonds with ATP
32
What does a dehydrogenase do?
Removes H with a cofactor
33
What does a thio do?
Breaks S bonds
34
What is diffusion?
From high to low concentration
35
What is active transport?
Goes against concentration gradient
36
What is zero-order kinetics?
Metabolism, independent of concentration
37
What is 1st order kinetics?
Constant drug percentage metabolism over time, depends on drug
38
What is efficacy?
Max effect regardless of dose
(Lower w/ non-competitive antagonist)
39
What affects efficacy?
Vmax
40
What is potency?
Amount of drug needed to produce effect
(Lower w/ competitive antagonist)
41
What affects potency?
Km
42
What is Kd?
Concentration of drug that binds 50% of receptors
43
What is EC50?
Concentration of drug that produces 50% of maximal response
44
What is competitive inhibition?
Fights for active site
No change in Vmax
Potency decreases
45
What is non-competitive inhibition?
Binds a regulatory site
No change in Km
Efficacy decreases
Decr Vmax
46
What is an endothermic reaction?
Pos delta G
Consumes heat
47
What is an exothermic reaction?
Neg delta G
Gives off heat
Ex: spontaneous reaction
48
What is the peak level?
4 hrs after dose
(Too high => decrease dose)
49
What is the Trough level?
2 hours before dose
(Too high => give less often)
50
What is t1/2?
Half-life
= time it takes for the body to use half of the drug ingested
51
What is Von Gierke?
G6P-ase deficiency
=> hypoglycemia, hepatosplenomegaly
52
What is Pompe’s?
Cardiac alpha-1,4-glucosidase deficiency
=> die early
Heart failure in child
53
What is Cori’s?
Debranching enzyme deficiency
=> short branches of glycogen
54
What is Anderson’s?
Branching enzyme deficiency
=> long chains of glycogen
55
What is McArdle’s?
Muscle phosphorylase deficiency
=> muscle cramps w/ exercise
56
What is Essential fructosuria?
Fructokinase deficiency
=> excrete fructose
(Still have hexokinase)
57
What is fructosemia?
Fructose intolerance
(Aldolase B deficiency)
=> liver damage
58
What does a galactokinase deficiency cause?
Cataracts
59
What does Galactosemia cause?
Cataracts
Mental retardation
Liver damage
60
What does citrate shuttle do?
FA transport out of the mitochondria
61
What does the carnitine shuttle do?
FA transport into the mitochondria
62
What lysosomal diseases have a cherry-red macula?
Tay-Sachs (ß-hexosaminadase A deficiency)
Niemann-Pick (sphingomyelinase deficiency)
63
What lysosomal diseases have a Gargoyle-face?
Gaucher’s (glucocerebrosidase deficiency)
Hurler’s (alpha-L-iduronidase deficiency)
64
What is Tay-Sach’s?
Hexosaminidase A deficiency =>
- blindness
- incoordination
- dementia
65
What is Sandhoff’s?
Hexosaminidase A/B deficiency
66
What is Gaucher’s?
Glucocerebrosidase deficiency =>
- “wrinkled tissue paper” nuclei
- bone pain
67
What is Neimann-Pick?
Sphingomyelinase deficiency
=> zebra bodies
68
What is Fabry’s?
Alpha-galactosidase deficiency =>
- corneal clouding
- attacks baby’s kidneys
- X-linked recessive
69
What is Krabbe’s?
ẞ-galactosidase deficiency
=> globoid bodies
70
What is metachromatic leukodystrophy?
Arylsulfatase deficiency
=> childhood MS
71
What is Hunter’s?
Iduronidase deficiency
=> milder form
72
What is Hurler’s?
Iduronidase deficiency
=> severe form
73
What is Lesch-Nyhan?
HGRPRT deficiency =>
- gout
- neuropathy
- self-mutilation
- X-linked recessive
74
What do white diaper crystals suggest?
Excess orotic acid
75
What does biotin donate CO2 groups for?
Carboxylation
76
What does THF donate methyl groups for?
Nucleotides
77
What does SAM donate methyl groups for?
All other reactions
78
What is the difference b/w heterochromatin and euchromatin?
Heterochromatin = tightly coiled
Euchromatin = loose (10 nm)
79
What are the purines?
Adenine
Guanine
80
What are the pyrimidines?
Cytosine
Uracil
Thymine
CUT the pyramid
81
What is a silent mutation?
Changes leave the same amino acid
82
What is a point mutation?
Changes 1 base
83
What is a transition?
Changes 1 purine to another purine or pyrimidine to pyrimidine
84
What is a transversion?
Changes 1 purine to pyrimidine or vice versa
85
What is a frameshift mutation?
Insert or delete 1-2 bases
86
What is a missense mutation?
Mistaken amino acid substitution
87
What is a nonsense mutation?
Early stop codon
88
What does a Southern blot defect?
DNA
89
What does a Northern blot detect?
RNA
90
What does a Western blot detect?
Protein
91
What are the essential amino acids?
PVT TIM HALL
- Phe
- Val
- Trp
- Tyr
- Ile
- Met
- His
- Ala
- Leu
- Lys
92
What are the essential fatty acids?
Linolenic
93
What are the acidic amino acids?
Asp
Glu
94
What are the basic amino acids?
Lys
Arg
95
What are the sulfur-containing amino acids?
Cys
Met
96
What are the O-bond amino acids?
Ser
Thr
Tyr
97
What are the N-bond amino acids?
Asn
Gln
98
What are the branched amino acids?
Leu
Ile
Val
99
What are the aromatic amino acids?
Phe
Tyr
Trp
100
What is the smallest amino acid?
Glycine
101
What are the ketogenic amino acids?
Lys
Leu
102
What are the glucogenic & ketogenic AA?
PITT
- Phe
- Ile
- Thr
- Trp
103
What amino acids does Trypsin cut?
Lys
Arg
104
What amino acids does ß ME cut?
Cys
Met
105
What amino acids does acid hydrolysis denature?
Asn
Gln
106
What amino acids does chymotrypsin cut?
Phe
Tyr
Trp
107
What amino acid turns yellow on Nurhydrin reaction?
Pro
108
What does carboxypeptidase cut?
Left of any amino acid on the carboxy terminal
109
What does CNBr cut?
(Cyanogen bromide)
Right of Methionine
110
What does aminopeptidase cut?
Right of N terminus
111
What does mercaptoethanol cut?
Right of Cys, Met
112
What does elastase cut?
Right of Gly, Ala, Ser
113
What does Trypsin cut?
Arg
Lys
114
What does chymotrypsin cut?
Phe
Tyr
Trp
115
What does alpha-1-antitrypsin do?
Inhibits trypsin from getting loose
116
What is PKU?
No Phe -> Tyr (via PheHydroxylase)
- nutrasweet sensitivity
- mental retardation
- pale
- blond hair
- blue eyes
- musty odor
117
What is albinism?
No Tyr -> melanin
(Via tyrosinase)
118
What is maple syrup urine disease?
Defective metabolism of branched AA (Leu, Ile, Val)
=> AA leak out
119
What is Homocystinuria?
No homocysteine -> Cys
“COLA” stones
- Cysteine
- Ornithine
- Lysine
- Arginine
120
What is Pellagra?
Niacin deficiency
- dermatitis
- diarrhea
- dementia
- death
121
What is Hartnup’s?
No tryptophan => niacin + serotonin
Presents like pellagra’s
Can mimic corn-rich diet
122
What causes anterior leg bowing?
Neonatal syphilis
123
What causes lateral leg bowing?
Rickets
124
What are the names of the B vitamins?
“The Rich Never Lie about Panning Pyrite Filled Creeks”
- B1 = Thiamine
- B2 = Riboflavin
- B3 = Niacin
- B4 = Lipoic acid
- B5 = Pantothenic acid
- B6 = Pyridoxine
- B9 = Folate
- B12 = Cobalamin
125
What does Vit A do?
Night vision
CSF production
PTH
126
What does Vit B1 do?
Cofactors for:
- Dehydrogenases
- Transketolase (PPP)
127
What does Vit B2 do?
FAD cofactor
128
What does Vit B3 do?
NAD cofactor
or
NADP
129
What does Vit B4 do?
Glycolysis
No known diseases
130
What does Vit B5 do?
Part of Acetyl CoA
No known diseases
131
What does Vit B6 do?
Transaminase cofactor
Myelin integrity
132
What does Vit B9 do?
Nuclear division
133
What does Vit B12 do?
Cofactor for:
- homocysteine methyltransferase (HMT)
- methlyl-malonyl CoA mutase (MMM)
134
What does Vit C do?
Collagen synthesis
135
What does Vit D do?
Mineralization of bones, teeth
136
What does Vit K do?
Clotting factors
137
What does biotin do?
Carboxylation
(= cofactors of carboxylases)
138
What does Calcium do?
Neuronal function
Atria depolarization
SM contractility
139
What does Cu(2+) do?
Collagen synthesis
140
What does Fe(2+) do?
Hb function
Electron transport
141
What is Bronze pigmentation?
Fe deposit in skin
142
What is Bronze cirrhosis?
Fe deposit in liver
143
What is Bronze diabetes?
Fe deposit in pancreas
144
What is hemosiderosis?
Fe overload in bone marrow
145
What is hemochromatosis?
Fe deposit in organs
146
What does Magnesium do?
PTH and kinase cofactor
147
What does Zinc do?
Taste buds
Hair
Sperm function
148
What does Chromium (Cr) do?
Insulin function
149
What does Molybdenum do?
Purine breakdown
(Cofactor for xanthine oxidase)
150
What does manganese (Mn) do?
Glycolysis
151
What does Selenium (Se) do?
Heart function => dilated cardiomyopathy
152
What does tin (Sn) do?
Hair
153
What is Kwashiorkor?
Malabsorption
Big belly (ascites)
Protein deficiency
154
What is Marasmus?
Starvation
Skinny
Calorie deficiency
155
Where does the Pre- label send stuff to?
RER
prE = rEr
156
Where does the Pro- label send stuff to?
Golgi
prO = gOlgi
157
Where does the mannose-6P send stuff to?
Lysosome
158
Where does the N-terminal sequence send stuff to?
Mitochondria
159
What are the 4 types of collagen?
SCAB
- Type I: Skin, bone
- Type II: Connective tissue, aqueous humor
- Type III: Arteries
- Type IV: Basement membrane
160
How does Scleroderma present?
Tight skin
161
How does Ehler’s Danlos present?
Hyper-stretchable skin
162
How does Marfan’s present?
Hyperextensible joints
Arachnodactyly
Wing span longer than height
Aortic root dilatation
Aortic aneurysm
Mitral valve prolapse
Dislocated lens from bottom of eye -> look up
163
How does homocystinuria lens present?
Dislocated lens from top -> look down
164
How does kinky hair disease present?
Hair looks like copper wire
(= copper deficiency)
165
How does scurvy present?
Bleeding gums
Bleeding hair follicles
166
How does Takayasu arteritis present?
Asian female with very weak pulse
167
How does osteogenesis imperfecta present?
Shattered bones
Blue sclera
