Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biochemistry 1 > Test 3 questions and answers > Flashcards

Test 3 questions and answers Flashcards

1
Q

The main site for gluconeogenesis is:

A. liver
B. muscle
C. kidney
D. brain

A

A. liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The glycosidic bond:

A. in maltose is not hydrolyzed in lactose intolerant humans
B. in sucrose is hydrolyzed by bees
C. joins glucose and fructose to form sucrose
D. both (B) and (C)

A

D. both B and C are correct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Glycogen degradation requires the enzymes namely:

A. glycogen synthase and phosphorylase
B. glycogen phosphorylase and glycogen-debranching enzyme
C. glycogen dehydrogenase and glycogen-debranching enzyme
D. glycogen kinase and glycogen splitting enzyme

A

B. glycogen phosphorylase and glycogen-debranching enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Two major products of the pentose phosphate pathway are:

A. NADPH and NAD
B. FAD and CoA
C. flavine adenine dinucleotide and glucose 5-phosphate
D. nicotinamide adenine dinucleotide and ribose 5-phosphate

A

D. nicotinamide adenine dinucleotide and ribose 5-phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

A catabolic intermediate which stimulates phosphofructokinase would stimulate:

A. glycogen synthesis
B. glycolysis
C. gluconeogenesis
D. glycogenolysis

A

B. glycolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A fatty acid with 14 carbon atoms will undergo how many cycles of beta oxidation?

A. 14
B. 7
C. 6
D. 1

A

C. 6 cycles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which of the following is the primary ketone body?

A. Acetone
B. Acetoacetate
C. Beta-hydroxy buterate
D. Hydroxy Methyl glutarate

A

B. acetoacetate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Choose the INCORRECT statement about cholesterol synthesis:

A. All the carbon atoms are derived from Acetyl-CoA
B. Process is cytoplasmic
C. NADPH is the main coenzyme
D. Highly expensive energetically

A

B. process is cytoplasmic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Lipolysis of triacylglycerols is stimulated by:

A. insulin
B. glucagon
C. ATP
D. dopamine

A

B. glucagon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which lipoprotein has the highest content of protein?

A. VLDL
B. LDL
C. HDL
D. Chylomicrons

A

C. HDL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which lipoprotein has lowest content of protein

A

Chylomicrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which fatty acid is this?

A

Stearic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which apolipoproteins transport dietary triglycerides from intestines

A

Chylomicrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Hormones stimulating lipolysis

A

Epinephrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are fatty acids transported in the bloodstream

A

Bound to albumin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Number of beta-oxidation cycles needed to oxidise a fatty acid (no, of carbons 12) - 1

A

Depends on the length of the fatty acid and chain, for 12 its 5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How many ATP molecules are required for activation of fatty acids?

A

2 ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Important enzyme in ketogenesis

A

HMG CoA synthase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does dietary glucose enter cytoplasm of enterocytes

A

By symport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What phospho sugar is this?

A

Glucose-1-phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is predominant glucose transporter present on surface of erythrocytes

A

Glut 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Glut 2 happens where?

A

In the liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Glut 3 happens where?

A

In the kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Alpha - 1,4 bonds are hydrolyzed by enzyme called..

A

Amylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

An enzyme phosphoglucomutase transforms

A

Glucose - phosphate to glucose-6-phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Hormones promoting glucagon dehydration

A
  • Glucagon
  • Epinephrine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Hormones involved in gluconeogenesis

A
  • Glucagon
  • Norepinephrine
  • Epinephrine
  • Cortisol
  • Thyroid + growth hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Choose activated sugar which a substrate of glycogen synthase

A

UPD glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Animals which have increased contents of fast twitch myocyte fibres

A
  • Rabbit
  • Cat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Net energy profit from degradation of one glucose molecule through glycolysis is

A
  • 2 ATP
  • 2 NADH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Propianate CoA generated after beta oxidation of odd number fatty acids is transformed into..

A

Succinyl CoA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Organs that metabolise ketone bodies

A
  • Brain
  • Heart
  • Skeletal muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is source of two carbon units for fatty acid synthesis

A
  • Acetyl CoA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Fatty acid synthase of mammals contains

A
  • 7 enzymatic activities and ACP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Common precursor of triglyceride + glycerophospholipid synthesis is

A
  • Phosphatic acid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Compound having a major role in regulation of fatty acid synthesis + breakdown

A
  • Molony CoA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Glycosidic bonds present in glycogen

A
  • A-1,4
  • A-1,6
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Which organ expresses an enzyme glucose-6-phosphate (gluconeogenesis)

A
  • Liver
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Products of glucogen hydrolysis

A
  • Glucose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Name of protein in center of glucagon

A
  • Glucogenin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Hormones stimulating lipolysis

A
  • Cortisol
  • Glucagon
  • epinephrine
  • Norepinephrine
  • Growth hormone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

How are free fatty acids transported in bloodstream

A
  • Bound to albumin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How are steroid hormones transported in blood

A
  • bound to globulins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Enzymes operating during b-oxidation of fatty acids

A
  • Acyt CoA dehydrogenase
  • Thiolase
  • Enoyl CoA hydratase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

How many b-oxidation cycles are necessary to completely degrade one molecule of stearate

A
  • 8
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

2 enzymes requiring the same cofactor + using is the same catalytic mechanism

A
  • pyruvate dehydrogenase
  • Alpha-ketoglutarate dehydrogenase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Product of fumerase enzyme

A
  • Maleate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

How many high energy electrons are produced from the oxidation of one acetyl CoA in krebs cycle

A
  • 8
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Which apolipoproteins transport dietary triglycerols from intestine

A
  • Chylmirons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Enzyme playing major role in controlling rate of glycolysis

A
  • Phosphofructo kinase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Irreversible glycolysis reaction

A
  • Glucose –> glucose-6-phospate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Products of the oxidative phase of pentose phosphate pathway

A
  • nucleotide sugars
  • NADPH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What enzyme mediates this reaction

A
  • Lactate dehydrogenase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Metabolites of non-oxidative phase of pentose pathway that have direct link with glycolysis

A
  • Fructose-6-phosphate
  • 3 phosphoglyceraldehyde
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

In the process of glycolysis, 1 glucose molecule converts to..

A

2 pyruvate molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Compounds that inhibit activity of phosphofructo kinase

A
  • Citrate
  • ATP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Metabolic target of oxidative phase of pentose phosphate pathway

A
  • NAD+ reduction
  • Synthesis of nucleotide precursors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Enzyme of non-oxidative phase of the pentose pathway transferring two-carbon fragments of sugar is

A
  • Transketolase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

The presence of pyridoxal phosphate (PLP) is necessary for what reaction

A
  • Conversion of glucose-1-phosphate to glucose-6-phosphate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

In corich cyde, working muscles secrete in blood..

A
  • Lactate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Steps in glycolysis that lead to breakdown glucose in order

A
  1. Conversion of glucose-6-phosphate to fructose-6-phosphate
  2. Cleavage of fructose-1,6-biphosphate to 2 phospho trioses
  3. Formation of 1,3-biphosphoglycerate
  4. converting 3 phosphoglycerate to 2 phosphoglycerate
  5. formation of phosphoenollpyruvate
62
Q

What is cellulose

A
  • Glucose homopolymer
63
Q

What process is the source of the main substrate of the krebs cycle containing 3 carbon

A
  • Glycolysis
64
Q

Compounds that are activators of dehydrogenase

A
  • ADP
  • ATP
65
Q

Bloodstream of fasted dogs

A
  • Ketone bodies
66
Q

Primary bile acid

A
  • cholic acids
  • chenodeoxycholic acid
67
Q

Common precursor of steroid hormones formed from cholesterol

A

Pregnenolone

68
Q

Which amino acid does not undergo transmination

A
  • proline
  • threonine
69
Q

What cellular compartment is glutamate dehydrogenase present

A
  • mitochondrial matrix
70
Q

What are products of arginase reaction

A
  • amithine and urea
71
Q

During beta-oxidation of fatty acids, propionyl-IN-CoA is converted to

A
  • Something CoA which enters citric acid cycle (succinyl)
72
Q

What enzyme catalyzes more than one reaction during oxidation

A
  • Dehydrogenase
73
Q

When oxaloacetate is unavailable, acetyl-CoA is converted

A
  • Acetone
  • Acetylacetate
  • B-hydroxybutrate
74
Q

The synthesis of C16 fatty acids proceeds

A
  • in the cytosol, with participation of NADPH
75
Q

Arachidonic acid is not a precursor of..

A

Cholesterol

76
Q

Non-steroid anti-inflammatory drugs are broad, heterogeneous group of anti-inflammatory, analgesic and antipyretic drugs, work by inhibiting activity of

A
  • Cycloxygenases
77
Q

Statin is a drug used to lower blood cholesterol. Works by inhibiting

A
  • 3-HMG-CoA reductases
  • mevalonate formation reaction
78
Q

High density lipoproteins..

A
  • Transport cholesterol from tissue to liver
  • Have apoprotein A, E + C in their composition
79
Q

Progesterone in hormone

A
  • Cholesterol derivatives, responsible for maintaining pregnancy
  • Allowing implantation of embryo into uterine mucosa
80
Q

The presence of pyridoxal phosphate (PLP) is necessary for what reaction

A
  • Glycogen breakdown catalyzed by glycogen phosphorylase
81
Q

Coric cycle

A
  • Lactate
82
Q

Which process is source of main substrate of krebs cycle containing 3 carbon atoms

A
  • Glycolysis
83
Q

Product of glycogen hydrolysis

A
  • Glucose
84
Q

Irreversible glycolysis reaction

A
  • Phosphoenolpyruvate -> pyruvate
85
Q

Production from oxidate of PPP

A
  • nucleotide sugars
  • NADPH
86
Q

Glucagon + Epinephrine

A
  • Stimulates gluconeogenesis + inhibits glycolysis
86
Q

Catabolic intermediate stimulating phosphofructokinase will also stimulate

A
  • Glycolysis
87
Q

Arachidonic acid is a precursor of

A
  • Prostaglandins
  • Leukotrienes
  • Prostacyclin
88
Q

In which cell does the rapapo-lubering shunt operate

A
  • Erythrocytes
89
Q

In liver, dietary fructose is converted to

A

Fructose-1-phosphate

90
Q

Enzyme mediating this reaction

A
  • Pyruvate carboxylase
91
Q

Products of oxidative phase of pentose phosphate pathway

A
  • NADPH
  • Nucleotide sugars
92
Q

Enzyme controlling rate of pentose phosphate pathway

A
  • Glucose-6-phosphate dehydrogenase
93
Q

Beta oxidation of fatty acids takes place in

A
  • Mitochondrium
94
Q

Synthesis of fatty acids takes place in

A
  • Cytoplasm
95
Q

Krebs cycle takes place in

A
  • Mitochondrium
96
Q

Biological functions of cholesterol

A
  • Precursor of bile acids
  • Precursor of vitamin D
  • Precursor of steroid hormones
  • Component of lipid rafts
97
Q

What is the proportion of de novo cholesterol synthesis relation to dietary cholesterol uptake

A
  • 85%
98
Q

Lipoprotein that has the highest cholesterol contents

A
  • LDL
99
Q

Lipids in the bilayer

A
  • Inner
    –> Phosphatidylserine
    –> Linositol
    –> Lethanolamine
  • Outer
    –> Phosphatidylcholine
    –> Glycolipids
    –> Glycoproteins
  • Both
    –> Cholesterol
100
Q

Key enzyme that allows the use of ketone bodies as an energy source in extracellular tissues

A
  • CoA transferase
101
Q

What is the source of Acetyl-CoA needed for synthesis of fatty acids in cytoplasm

A
  • Citrate
102
Q

What is function of APO-11

A
  • Activates lipoprotein lipase
103
Q

Factors that promote cholesterol synthesis in liver

A
  • Insulin
  • Low concentration of non-steroidal mevalonate metabolism
104
Q

HMG-CoA synthase is involved in synthesis of

A
  • Cholesterol
  • Ketone bodies
105
Q

Name of aminotransferase that performs following RXN

A
  • Aspartate aminotransferase
106
Q

Correct type of LDL update mechanism

A
  • Receptor-mediated endocytosis
107
Q

Consequences of LDL receptor deficiency

A
  • increased plasma cholesterol levels
  • Increased probability of coronary heart disease
  • Common xanthomas
108
Q

Organs in which cholesterol synthesis occurs

A
  • Liver
  • Ovaries
  • Adrenal cortex
109
Q

Enzyme targeted by statins

A
  • HMG-CoA reductase
110
Q

Correct rotation for squalene synthase reaction

A
  • CIS + CIS –> C30
111
Q

Factors inhibiting HMG-CoA reductase

A
  • Fasting
  • Cholesterol intake
  • Phosphorylation
112
Q

Primary bile acids

A
  • Cholic acid
  • Chenodeoxycholic acid
113
Q

Mineralocorticoid

A
  • Aldosterone
114
Q

Calcitriol (activate form of vit D) is generated from vitamin D3 by following modifications

A
  • Successive hydroxylations
115
Q

Steroid + peptide hormones are equally well cell permeable

A
  • false
116
Q

Peptide hormones more diverse than steroid

A
  • true
117
Q

Steroid hormones are same from species to species

A
  • true
118
Q

Steroid hormones can be stored in place of synthesis

A
  • false
119
Q

Peptide hormones are always bound to carrier protein

A
  • false
120
Q

Glycolysis stage 1

A
  • 2 ATP invested
  • Glucose is phosphorylated
  • Converted to fructose
  • Cleaved into 2 molecules = glyceraldehyde + 3 Phosphate
121
Q

Glycolysis stage 2

A
  • Glyceraldehyde 3 phosphate converted to pyruvate
  • Generates 4 ATP + 2 NADH = only 2 ATP used
122
Q

How is glycolysis regulated

A
  • substrate + enzyme is limited
123
Q

Enzymes regulated in glycolysis

A
  • Hexokinase
  • Phosphofructo kinase
  • Pyruvate kinase
124
Q

ATP in glycolysis + gluconeogenesis

A
  • 2 ATP made in glycolysis
  • 4 ATP used in gluconeogenesis
125
Q

How does fructose 2,6-biphosphate regulate glycolysis + gluconeogenesis

A
  • Activates phosphofructokinase-1
  • Activates transcription of hexokinase
  • Inhibits fructose 1,6-biphosphate
126
Q

3 fates of glucose 6-phosphate

A
  • glycolysis
  • glycogenolysis
  • pentose phosphate pathway
127
Q

Enzyme for glycogenesis

A
  • glycogen synthase
128
Q

Enzyme for reverse of glycogenesis

A
  • UDP glucose pyrophospyrase
129
Q

How is glycogen synthase regulated

A
  • Phosphorylation leads to inactivation
130
Q

Regulation of pentose phosphate pathway

A
  • first step irreversible
  • NADPH is inhibitor of glucose 6-phosphate dehydrogenase
  • Induced by insulin
131
Q

How many ATP molecules required for activation of fatty acids

A

2 ATP

132
Q

Location of ketogenesis

A
  • mitochondria
133
Q

Enzyme in ketogenesis

A
  • HMG CoA synthase
134
Q

Final product of lipogenesis

A
  • palmitic acid C16
135
Q

What activates lipogenesis

A
  • Insulin
  • High blood glucose
136
Q

Coenzymes of lipogenesis

A
  • NADPH
  • NADP+
137
Q

Regulation of lipogenesis

A
  • activated by insulin
  • deactivated by glucagon epinephrine
138
Q

LDL

A

Low Density, more lipid than protein

139
Q

HDL

A

High density protein + lipoprotein, low lipid content

140
Q

VLDL

A

Very Low Density, high lipid content, low protein

141
Q

excess fat stored in

A

Lipocytes

142
Q

Location of de nobo synthesis of cholesterol

A
  • liver
  • secondary sites: adrenal cortex, ovaries and testes
143
Q

Energetic cost of de novo synthesis of cholesterol

A

18 ATP

144
Q

Enzyme in de novo synthesis of cholesterol

A

HMG CoA synthase

145
Q

Regulating step of de novo synthesis of cholesterol

A

HMG CoA to mevalonade

146
Q

HMG CoA inhibited by

A

Statins

147
Q

Location of HMG CoA enzyme

A
  • Endoplasmic reticulum
148
Q

How many steps needed to convert squaline to cholesterol

A

19

149
Q

Half life of HMG - CoA

A

2 hours

Biochemistry 1 (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions