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1
Q

Two major metabolic amino acids from muscle protein degradation?

A

Alanine

Glutamine

2
Q

Which hormone stimulates adipose stores to mobilize?

A

Glucagon

3
Q

Which tissues metabolize glutamine?

A

GUT

Kidney

4
Q

Besides protons, what else can decrease the affinity of HbA for O2?

A

2,3-bisphosphoglycerate (BPG or DPG)

5
Q

At normal pH, amino groups have what charge?

A

Positive

6
Q

Branched chain amino acids.

A

Valine (V)
Leucine (L)
Isoleucine (I)

7
Q

The n-side chain is a common site for what?

A

Glycosylation

8
Q

Positively charged basic molecules

A

Arginine (R)
Lysine (K)
Histidine (H)

9
Q

Bonds that held Cystine.

A

Disulfide bonds

10
Q

Amino acid that causes kinks in the peptide chain.

A

Proline

11
Q

Primary hemoglobin in adults.

A

HbA

12
Q

If the body wants to release oxygen, which form of hemoglobin will it use? If it wants to uptake oxygen?

A

Taut; Relaxed

13
Q

Hexokinase and Glucokinase are what kind of molecules?

A

Isozyme

14
Q

The only site that can reverse or dephosphorylate glucose-6-phosphate and export glucose?

A

Liver

15
Q

Rate limiting enzyme of glycolysis.

A

Phosphofructokinase 1

PFK-1

16
Q

Products of aerobic glycolysis.

A

Pyruvate

17
Q

Products of anaerobic glycolysis.

A

Lactate

18
Q

Site of glycolysis.

A

Cytosol

19
Q

2 requirements for aerobic glycolysis.

A

Oxygen

Mitochondria

20
Q

ATPs produced when using malate aspartate shuttle.

A

5 ATP

21
Q

In hypoxia, what happens to 2,3-BPG in RBC’s?

A

Increases

22
Q

Enzyme that adds phosphate from ATP to a molecule’s hydroxyl group.

A

Kinase

23
Q

Aerobic NADH reoxidation to NAD+ occurs via what process?

A

Oxidative phosphorylation

24
Q

2,3-BPG is produced via?

A

Glycolysis

25
Q

Inorganic component (minerals) essential to make the reaction work

A

Cofactor

26
Q

Organic component (vitamins) essential to make the reaction work

A

Coenzyme

27
Q

Complete enzyme: functional enzyme.

A

Holoenzyme

28
Q

Enzyme missing cofactor or coenzyme.

A

Apoenzyme

29
Q

Enzyme precursor: Must be converted to active form.

A

Zymogen

30
Q

Adds water, CO2 or ammonia to doubble bond or removes them from double bond.

A

Lyase

31
Q

When [s] = km, them Vo = ?

A

1/2 Vmax

32
Q

When Vo = 1|2 Vmax then [s] = ?

A

Km

33
Q

If the concentration of substrate [s] is smaller than Km, what is the reaction dependant on?

A

Substrate

Competitive inhibition

34
Q

When the concentration of substrate is bigger than Km, what is the reaction dependant on?

A

Non competitive inhibition

35
Q

In Phosphorylation of glycogen phosphorylase, ____ activity

A

Increases

36
Q

In Phosphorylation of glycogen synthase, ____ activity

A

Decreases

37
Q

Regulatory enzymes in a cascade (rate limiting). Activator or inmhibitor binds to an allosteric site on the enzyme. Feedback inhibition. Tells the enzyme to speed up or slow down. Act like a noncompetitive inhibitor.

A

Allosteric Enzymes

38
Q

Two specialized products derived from Tryptophan?

A

Serotonin, Niacin (NAD, NADP)

39
Q

GABA is derived from which amino acid?

A

Glutamine

40
Q

One specialized product that uses the entire structure of glycine?

A

Heme

41
Q

What enzyme combines succinyl-CoA and glycine to start the Heme pathway?

A

ALA (aminolevulinic acid) synthetase

42
Q

The rate of the reaction at saturation substrate concentrations for a given amount of enzyme.

A

Vmax

43
Q

The substrate concentration that results in 50% Vmax.

A

Km

44
Q

Competitive inhibitors ____________ (increase / decrease) the apparent Km.

A

Increase

45
Q

An inhibitor that binds to, and takes an enzyme out of commission is called a ____________ inhibitor.

A

Noncompetitive inhibitor

46
Q

NAD is synthesized from what vitamin?

A

Niacin (B3)

47
Q

FAD is synthesized from what vitamin?

A

Riboflavin (B2)

48
Q

TPP is what vitamin?

A

Thiamine (B1)

49
Q

What would competitive inhibition affect km or vmax?

A

Km

50
Q

In noncompetitive inhibition, what is changed?

A

Vmax

51
Q

Alzheimer’s disease has what specific plaque formation?

A

Beta amyloid

52
Q

How many CO2 released in TCA?

A

2

53
Q

When alpha-keto acids enter the TCA cycle what are the final products?

A

CO2, H2O, ATP

54
Q

Enzyme deficient in Maple Syrup Urine Disease.

A

Branched-chain Alpha-keto acid dehydrogenase

55
Q

L-glucose and D-glucose are examples of.

A

Enantiomers

56
Q

Most predominant carbohydrate enantiomer in humans.

A

D

57
Q

Monosaccharides that have the same chemical formula and different structural formula.

A

Isomers

58
Q

Monosaccharides that are Epimers at C4.

A

Glucose and Galactose

59
Q

Monosaccharides that are Epimers at C2.

A

Glucose and Mannose

60
Q

What is the linkage between a pentose sugar and purine/pyrimidine?

A

beta-glycosidic linkage

61
Q

Galactose in the lens of children with untreated galactosemia get?

A

Galactitol formation

62
Q

What kind of sugar is lactose?

A

reducing sugar

63
Q

What should be avoided in diet in children with Aldolase B deficiency?

A

Fructose

64
Q

Cellulose composition and linkages.

A

glucose linked by beta 1-4 glycosidic linkages

65
Q

Describe Vmax and Km for glucokinase vs. hexokinase?

A

Glucokinase Vmax and Km is higher. than hexokinase

66
Q

Which steps in glycolysis are irreversible?

A

1) hexokinase/glucokinase
2) PFK-1
3) Pyruvate kinase enzyme reactions

67
Q

Blocks enolase from converting 2 phosphoglycerate into phosphoenol pyruvate in glycolysis.

A

Fluoride

68
Q

What is the fate of pyruvate in aerobic conditions?

A

Converted to acetyl CoA by pyruvate dehydrogenase and enters TCA cycle

69
Q

What is the fate of pyruvate in anaerobic conditions?

A

Converted to lactate by lactate dehydrogenase and goes to liver via Cori cycle

70
Q

Enzyme converts Pyruvate to Lactate.

A

LDH

71
Q

What happens to the NADH formed in glucose under aerobic conditions?

A

Each NADH is used in ETC to produce 3 ATP (in malate-aspartate) 2 ATP (in glycerol-phosphate shuttle).

72
Q

What happens to the 2,3 BPG level in people from high altitudes?

A

Increased

To facilitate unloading of oxygen.

73
Q

What is the second most common form of hemolytic anemia?

A

Pyruvate kinase deficiency in RBCs

74
Q

What is the most common form of hemolytic anemia?

A

G6PD deficiency

75
Q

What effect when tumor cells use glycolysis as the main source of ATP

A

Warburg effect

76
Q

Makes a phosphodiester bond between adjacent nucleotides in DNA.

A

DNA Ligase

77
Q

The biochemical function of cAMP is to activate _______________.

A

Protein kinase A

78
Q

Has a high Km for glucose and is active after a big meal.

A

Glucokinase

79
Q

The enzyme primarily responsible for metabolizing alcohol.

A

Alcohol dehydrogenase

80
Q

Stimulates the activity of phosphofructokinase-1 (PFK-1).

A

Fructose 2,6-bisphosphate

81
Q

Rate limiting enzyme in cholesterol biosynthesis.

A

HMGCoA reductase

82
Q

Catalyzes the first step in glycolysiss that produces ATP by substrate-level phosphorylation.

A

Phosphoglycerate kinase

83
Q

Synthesizes cAMP

A

Adenyl cyclase

84
Q

Breaks down cAMP

A

Phosphodiesterase

85
Q

Precursor of Tyrosine.

A

Phenylalanine

86
Q

Where is arginine created?

A

Urea cycle

87
Q

2 Hormones stimulate amino acid uptake into the liver.

A

Glucagon

Cortisol

88
Q

Spans the inner membrane, the proton channel

A

Fo domain

89
Q

Extended out into the matrix, the catalytic subunit

A

F1 domain

90
Q

Inhibits ATP synthase by binding to the F0 domain thus closing the proton channel, electron transport is halted.

A

Oligomycin

91
Q

Deficiency in PKU.

A

Phenyalanine hydroxylase

92
Q

Stimulated by diacylglycerol (DAG) and inositol trisphosphate 3 (IP3)

A

Protein Kinase C

93
Q

Cleaves phosphodiester bonds

A

Nuclease

94
Q

Rate-limiting step of the Pentose Phosphate Pathway

A

Glucose-6-P Dehydrogenase (GPDH)

95
Q

Allow for interconversion of diasteromers

A

Epimerase

96
Q

Transfers a 3-carbon fragment from one sugar to another

A

Transaldolase

97
Q

Rate-limiting step of fatty acid synthesis (requires biotin)

A

Acetyl CoA carboxylase

98
Q

Transfers an electron from NADPH to the heme Fe in P450, reducing the Fe(III) to Fe(II)

A

Cytochrome P450 reductase

99
Q

Inhibited in Complex I of the ETC.

A

NADH dehydrogenase

100
Q

Inhibited in Complex III of the ETC.

A

Cytochrome c reductase

101
Q

Inhibited in Complex IV of the ETC.

A

Cytochrome oxidase

102
Q

Prevents Phosphoglycerate kinase ATP production

A

Arsenate

103
Q

Enzyme that overcomes the irreversible pyruvate kinase reaction in glycolysis.

A

Phosphoenolpyruvate carboxykinase

104
Q

The toxic effects of cyanide are due to _________________.

A

inhibition of cytochrome oxidase (Complex IV)

105
Q

Enzyme unique to the Pentose Phosphate Pathway

A

Transketolase

106
Q

An enzyme that removes a phosphate from the substrate.

A

Phosphatase

107
Q

Where are free amino acids absorbed?

A

Small intestine

108
Q

How are fructose absorbed?

A

Facilitated diffusion

109
Q

GLUT 2 can be found in?

A

Basement membrane

110
Q

Transport found in Luminal membrane.

A

GLUT 5

111
Q

How many ATP produced in ETC?

A

30 or 32 ATP

112
Q

Cofactors required in conversion of propionyl CoA to Succinyl CoA. r

A

Biotin and vitamin B12

113
Q

(+) delta H

A

Endothermic reaction

114
Q

(-) delta H

A

Exothermic reaction

115
Q

A molecule with two charges but no net charge.

A

Zwitterion

116
Q

pH = pKa + (log[A-]/[HA])

A

Henderson Hasselbalch equation

117
Q

Glucose + Galactose

A

Lactose

118
Q

Glucose + Fructose

A

Sucrose

119
Q

Glucose + Glucose

A

Maltose

120
Q

Essential Fatty Acids

A

Linoleate and Linolenate

121
Q

Amino acid with no side chain, functions as inhibitory neurotransmitter and inhibited by strychnine

A

Glycine

122
Q

Infants are unable to utilize oxidized glucose (glucoronic acid) to conjugate the drug chloramphenicol(antibiotic) results in high levels and toxicity

A

Grey baby Syndrome

123
Q

The spatial arrangement of an organic molecule that is conferred by the presence of either (1) double bonds, about which there is no freedom of rotation, or (2) chiral centers, around which substituent groups are arranged in a specific sequence.

A

Configuration

124
Q

A spatial arrangement of substituent groups that are free to assume different positions in space, without breaking any bond, because of freedom of rotation

A

Conformation

125
Q

Compounds that have the same composition and the same order of atomic connections but different molecular arrangements

A

Stereoisomer

126
Q

Inhibitors that blocks NADH dehydrogenase/complex I.

A

AMYTAL
Rotenone
Piericidin

127
Q

Inhibitors that blocks complex III by preventing the oxidation of ubiquinol.

A

Antimycin A

128
Q

reversible inhibitor of cytochrom oxidase, binds to Fe3+ heme group.

A

Cyanide

129
Q

Compound in rat poison that inhibit aconitase.

A

Fluoroacetate

130
Q

Found in brain; Highly expressed in erythrocytes and high affinity for glucose

A

GLUT 1

131
Q

low affinity transporter, liver

A

GLUT 2

132
Q

high affinity transporter, brain

A

GLUT 3

133
Q

insulin sensitive, adipose and muscle

A

GLUT 4

134
Q

main type CT, bone, teeth, encapsulated organs resist force, tension and stretch

A

type I collagen

135
Q

cartilage resists intermittent pressure

A

type II collagen

136
Q

found in reticular fibers scaffolding for specialized cells

A

type III collagen

137
Q

basement membrane and filtration

A

type IV collagen

138
Q

skin, eye, etc connects basement membrane to ECM

A

type VII collagen

139
Q

The linear sequence of amino acids.

A

Primary Structure

140
Q

The association of two or more polypeptides into a multi-subunit complex.

A

Quaternary Structure

141
Q

Localized organization of parts of a polypeptide chain (e.g., the alpha helix or beta-pleated sheet).

A

Secondary Structure

142
Q

The overall, three-dimensional arrangement of the polypeptide chain.

A

Tertiary Structure

143
Q

covalent bond between two cys joining the subunits together

A

Disulfide bond

144
Q

The result of the misfold is an abnormal haemoglobin (HbS); the switch from Glu to Val causes the cell to want to stabilise (protect the hydrophobic regions) resulting polymerisation

A

Sickle cell disease

145
Q

Protein that can fold in multiple, structurally distinct ways, at least one of which is transmissible to other prion proteins; found on the surface of cells

A

Prion

146
Q

21st amino acid; non-coded amino acid; encoded by subset of STOP codons, contains Se instead of S; reduced pKa useful for enzymes in anti-oxidant activity

A

Selencysteine

147
Q

Carbon attached to the original carbonyl group in cyclic form

A

Anomeric carbon

148
Q

N-terminal of amino acid

A

Amino group

149
Q

C-terminal of amino acid

A

Carboxyl group

150
Q

The only form found in proteins

A

L-form amino acids

151
Q

Activation energy

A

ΔG

152
Q

Study of the rate of an enzyme catalysed reaction and how it varies.

A

Enzyme kinetics

153
Q

Initial reaction velocity, measured as soon as a substrate is mixed; rate of formation of the product.

A

V0

154
Q

Vo=(Vmax[S])/(Km+[S])

A

Michaelis-Menton equation

155
Q

Rearranging the Michaelis-Menten equation to the form y=mx+c; 1/Vo = (Km/Vmax[S]) + 1(Vmax); adds graphical value to the constant; can be used to determine the Km and Vmax as well to determine the action of enzyme inhibitors

A

Lineweaver-Burke plot

156
Q

One of the most common forms of regulation; good way of controlling enzyme activity; sigmoid curve (compared to hyperbolic curve of M-M kinetics); slow to start, but more rapid change that reaches Vmax quicker.

A

Allosteric regulation

157
Q

Also acts as a positive allosteric regulator of phosphenyolpyruvate to pyruvate (a later step in glycolysis);

A

Fructose 1,6-bis phosphate

158
Q

Large polymeric oligosaccharides, formed by the linkage of multiple monosaccharides are called

A

Polysaccharides

159
Q

What is the simplest aldose sugar?

A

Glyceraldehyde

160
Q

The interconversion of alpha and beta forms of a sugar (which occurs slowly in a solution) and leads to an equilibrium mixture of the two forms.

A

Mutarotation

161
Q

Shape of the graph of the Michaels-Menten equation.

A

Hyperbolic

162
Q

What is the relationship between the Michaels-Menten equation and the Lineweaver-Burk equation?

A

The LBE is a double reciprocal equation of the MME so as to give a linear graph to correctly identify the Km and Vmax.

163
Q

Vmax is unaffected but Km is increased.

A

Competitive inhibition

164
Q

Vmax is decreased but Km is decreased.

A

Uncompetitive inhibition

165
Q

Km is unaffected but Vmax is decreased.

A

Non-competitive inhibition

166
Q

Interactions are the most important in the folding of the peptide chain.

A

Hydrophobic

167
Q

Independent folding region that allows 1 protein to have multiple functions. Each domain has a specific function.

A

Domain

168
Q

Aid in protein folding during synthesis. They also prevent misfolding and protein aggregation

A

Chaperones

169
Q

What is ATP cleaved to for liberating energy?

A

ADP and Pi

170
Q

Final electron acceptor.

A

Oxygen

171
Q

Where does oxidative phosphorylation occur?

A

Inner Mitochondria

172
Q

The largest complex in the chain.

A

Complex I: NADH-Q Oxidoreductase.