Exam 1 Quizes Flashcards

1
Q

The best studied GAG is ____, which is secreted by cells in the lungs and other tissues in response to injury.

A

heparin

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2
Q

Although animals don’t synthesize starch, they possess an enzyme that readily hydrolyzes it. This enzyme is known as ___.

A

amylase

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3
Q

“Most often such chains are found covalently attached to lipids and proteins, converting them into glycolipids and glycoproteins.” In this sentence “chains” refer to ____.

A

oligosaccharides

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4
Q

Solid shortening, such as margarine are formed from ____ by chemically reducing the double bonds.

A

unsaturated vegetable oils

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5
Q

Not all biological polysaccharides consist of glucose monomers. An example of this is ___.

A

chitin

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6
Q

Which of the following has a carboxyl group?
A) acetic acid
B) ethyl alcohol
C) ethane
D) ethyl mercaptan

A

acetic acid

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7
Q

Which of the following is an example of a multiprotein complex?
A) myosin
B) myoglobin
C) pyruvate dehydrogenase
D) hemoglobin
E) actin

A

pyruvate dehydrogenase

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8
Q

Secondary structure is stabilized by ___. Tertiary structure is stabilized by an array of ____.

A

-hydrogen bonds
-non covalent bonds

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9
Q

Which of the following amino acid contains a sulfhydryl functional group?
A) proline
B) glycine
C) alanine
D) N-acetyglucosamine
E) cysteine

A

cysteine

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10
Q

The most widespread and important posttranslational modification is the reversible addition of a phosphate group to the following amino acids, EXCEPT ______.

A

lysine

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11
Q

Which of the following proteins constitute the machinery for biological movements?
A) antibodies and toxins
B) hormones and growth factors
C) membrane receptors and transporters
D) contractile filaments and molecular motors
E) enzymes and structural cables

A

contractile filaments and molecular motors

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12
Q

In the hemoglobin molecule of a person with sickle cell anemia, a nonpolar valine residue is present where a charged ___ is normally located.

A

glutamic acid

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13
Q

Vitamins and their derivatives often function as _____ in enzyme-catalyzed reactions.

A

cofactors

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14
Q

Which of the following is NOT true about enzymes?
A) They accelerate the rate at which a favorable reaction proceeds
B) They supply energy for a chemical reaction.
C) They are required only in small amounts.
D) They are not altered irreversibly during the course of a reaction.
E) They can participate repeatedly in individual reactions.

A

They supply energy for a chemical reaction.

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15
Q

One way to increase the reaction rate is to ____.
A) increase the energy of the reactants
B) increase the energy of the enzyme
C) increase the energy of the transition state
D) increase the activation energy

A

increase the energy of the reactants

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16
Q

The part of the enzyme molecule that is directly involved in binding the substrate is termed the ____.

A

active site

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17
Q

Which of the following will NOT accelerate a chemical reaction?
(Select 3)

A) increasing the reactivity of the substrate
B) stabilizing the the transition state
C) lowering the entropy of the substrate
D) increasing entropy of substrate
E) stabilizing the substrate
F) decreasing reactivity of substreate

A

stabilizing the substrate
increasing entropy of substrate
decreasing reactivity of substreate

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18
Q

The catalytic constant, which is the simplest measure of catalytic activity of an enzyme can be calculated from the ____.

A

maximal velocity

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19
Q

Which of the following is NOT true about enzymes?
A) They are not altered irreversibly during the course of a reaction.
B) They are required only in small amounts.
C) They can participate repeatedly in individual reactions.
D) They have no effect on the thermodynamics of the reaction.
E) They determine the ratio of products to reactants at equilibrium.

A

They determine the ratio of products to reactants at equilibrium.

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20
Q

Which of the following is not a noncovalent interaction?
A) hydrogen bond
B) peptide bond
C) ionic bond
D) hydrophilic interaction
E) hydrophobic interaction

A

peptide bond

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21
Q

The maximum number of molecules of substrate that can be converted to product by one enzyme per unit time is called ____.

A

turnover number

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22
Q

Which of the following is true?
A) The higher the delta G (i.e more positive), the faster the rate of reaction.
B) The magnitude of delta G informs us only of the difference in the free energy between the beginning state and equilibrium.
C)The magnitude of delta G is totally dependent on the time it takes to reach equilibrium.
D)The lower the delta G (i.e more negative), the faster the rate of reaction.

A

The magnitude of delta G informs us only of the difference in the free energy between the beginning state and equilibrium.

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23
Q

The term enzyme is generally reserved for ____ catalysts, while the term ____ is used for RNA catalysts.

A) inorganic, cofactor

B) protein, ribozyme

C) organic, coenzyme

D) DNA, ribosome

A

protein, ribozyme

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24
Q

Which of the following is NOT true about enzymes?

A) They can participate repeatedly in individual reactions.

B) They are not altered irreversibly during the course of a reaction.

C) They do not supply energy for a chemical reaction.

D) They are required only in small amounts.

E) They determine whether a reaction is thermodynamically favorable or unfavorable.

A

They determine whether a reaction is thermodynamically favorable or unfavorable.

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25
Q

If glucose is dissolved in water and kept sterile, it would not rapidly deteriorate because it is ___.

A) kinetically and thermodynamically stable

B) kinetically and thermodynamically unstable

C) kinetically stable, even if it is thermodynamically unstable

D) thermodynamically stable, even if it is kinetically unstable

A

kinetically stable, even if it is thermodynamically unstable

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26
Q

When a substrate enters the active site cleft, it typically gives up its ____.

A) hydrophobic environment

B) active site

C) bound water molecules

D) enzyme

E) cell

A

bound water molecules

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27
Q

The ___ provides a measure of the affinity of the enzyme for the substrate.

A) maximal velocity

B) initial reaction velocity

C) turnover number

D) Michaelis constant

E) state of saturation

A

Michaelis constant

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28
Q

Compounds formed in each step along a metabolic pathway are known as ____.

A) substrates

B) cosubstrates

C) reactants

D) end products

E) metabolites

A

metabolites

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29
Q

Glycolysis begins with the linkage of ____ to a phosphate group.

A) glucose-6-phosphate

B) starch

C) fructose-s-phosphate

D) sucrose

E) glucose

A

glucose

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30
Q

The redox reaction in glycolysis is catalyzed by ____.

A) triose phosphate isomerase

B) phosphoglyceromutase

C) aldolase

D) phosphoglycerate kinase

E) glyceraldehyde 3-phosphate dehydrogenase

A

glyceraldehyde 3-phosphate dehydrogenase

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31
Q

When oxygen levels become to low, skeletal muscle cells regenerate NAD+ by converting pyruvate to _____.

A) ethyl alcohol

B) lactate

C) acetaldehyde

D) acetyl-CoA

A

lactate

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32
Q

When cleaning with soap, greasy materials are converted into ____ that can be dispersed by water.

A) lipid bilayer

B) micelles

C) triacylglycerols

D) glycerol

E) fatty acids

A

micelles

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33
Q

Which of the following is a diacylglycerol?

A) glyceraldehyde

B) phosphatidylcholine

C) cholesterol

D) oleic acid

E) linseed oil

A

phosphatidylcholine

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34
Q

Starch is a mixture of two different polymers, _____.

A

amylose and amylopectin

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35
Q

In glyceraldehyde, carbon 2 is the ____.

A) asymmetric carbon

B) ketone

C) anomeric carbon

D) aldehyde (no)

A

asymmetric carbon

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36
Q

“If the hydroxyl group of this carbon projects to the right, the aldose is a D-sugar; if it projects to the left, it is an L-sugar.” The carbon referred to in this statement is ___.

A) asymmetric carbon associated with the aldehyde (no)

B) anomeric carbon associated with the aldehyde

C) anomeric carbon farthest from the aldehyde

D) asymmetric carbon farthest from the aldehyde

A

asymmetric carbon farthest from the aldehyde

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37
Q

Which of the following has a carbonyl group?

A) estrogen (no)

B) cholesterol

C) phosphatidylcholine

D) testosterone

A

testosterone

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38
Q

A straight-chain glucose molecule can be converted to a six-membered ring known as a ___.

A) aldose

B) furanose

C) hexose

D) pyranose

A

pyranose

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39
Q

The major component of plant cell walls is ____.

A

cellulose

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40
Q

The carboxyl group of a fatty acid is ____.

A) hydrophobic

B) saturated

C) hydrophilic

D) amphipathic

E) unsaturated

A

hydrophilic

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41
Q

Which of the following is a triacylglycerol?

A) cholesterol

B) phosphatidylcholine

C) linseed oil

D) oleic acid

E) glyceraldehyde

A

linseed oil

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42
Q

The difference between glucose and galactose is ___.

A) one is a monosaccharide, the other is a disaccharide

B) one is alpha, the other is beta

C) the configuration of the hydroxyl group in carbon 4

D) the number of asymmetric carbons

E) one is an aldose the other is a ketose

A

the configuration of the hydroxyl group in carbon 4

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43
Q

Which of the following proteins perform a wide variety of regulatory functions?

A) membrane receptors and transporters

B) hormones and growth factors

C) contractile filaments and molecular motors

D) enzymes and structural cables

E) antibodies and toxins

A

hormones and growth factors

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44
Q

Most soluble proteins are constructed so that the polar residues are situated at the ___ of the molecule.

A

surface

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45
Q

The ___ structure of a polypeptide is the specific linear sequence of amino acids that constitute the chain.

A

primary

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46
Q

A portion of a protein that is not composed of amino acids, and joined to the polypeptide chain after its assembly on the ribosome is called a ____.

A

prosthetic group

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47
Q

All amino acids have a/n _____.

A) amino group and carbonyl group

B) carbonyl group and hydroxyl group

C) carboxyl group and amino group

D) hydroxyl group and carboxyl group

E) amino group and hydroxyl group

A

carboxyl group and amino group

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48
Q

In an alpha helix, the ____ lies on the inside of the helix, and the ___ project outward.

A

backbone
side chains

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49
Q

Which of the following proteins determine what a cell reacts to and what types of substances enter or leave the cells?

A) membrane receptors and transporters

B) antibodies and toxins

C) hormones and growth factors

D) contractile filaments and molecular motors

E) enzymes and structural cables

A

membrane receptors and transporters

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50
Q

Hair is made of a large number of filaments composed of the cysteine rich protein keratin, cross-linked together by _____.

A

disulfide bridges

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51
Q

The ___ structure(s) in a protein refers to the conformation(s) of portions of the polypeptide chain.

A

secondary

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52
Q

The ____ in a protein consists of several segments of a polypeptide lying side by side.

A) amino acid

B) beta-sheet

C) peptide bond

D) disulfide bridge

E) active site

A

beta-sheet

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53
Q

Which of the following is a protein domain that mediates interaction between proteins?

A) catalytic domain

B) PH domain

C) chromodomain

D) SH3 domain

A

SH3 domain

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54
Q

All amino acids, except ____, have asymmetric carbons, and hence more than one stereoisomer.

A) proline

B) linolenic acid

C) glycine

D) N-acetyglucosamine

E) alanine

A

glycine

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55
Q

Mitochondria can fuse with one another or split in two. This splitting can be induced by ____.

A) mitosis

B) cytokinesis

C) meiosis

D) intermediate filaments

E) ER tubules

A

ER tubules

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56
Q

All of the enzymes in the TCA cycle reside in the soluble phase of the matrix, except for ____, which is bound to the inner membrane.

A) isocitrate dehydrogenase

B) succinate dehydrogenase

C) malate dehydrogenase

D) alpha-ketoglutarate dehydrogenase

A

succinate dehydrogenase

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57
Q

During the TCA cycle, four reactions occur in which a pair of electrons are transferred from a substrate to an electron accepting coenzyme. These reactions are catalyzed by ____.

A) FAD

B) NADH

C) dehydrogenases

D) coenzyme A

E) ATP

A

dehydrogenases

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58
Q

In the glycerol phosphate shuttle, electrons are transferred from NADH to ____ to form glycerol 3-phosphate, which shuttles them into the mitochondrion.

A) pyruvate

B) glycerol

C) dihydroxyacetone phosphate

D) aspartate

E) malate

A

dihydroxyacetone phosphate

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59
Q

The matrix of the mitochondrion has a gel-like consistency owing to the presence of a high concentration of _____.

A) proteins

B) carbohydrates

C) nucleic acids

D) lipids (no)

A

proteins

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60
Q

The inner mitochondrial membrane is virtually devoid of ____, and and rich in ____, which are characteristics of bacterial plasma membranes.

A) glycosaminoglycans, chitin

B) proteins, phospholipids

C) peptidoglycan, cellulose

D) cholesterol, cardiolipin

A

cholesterol, cardiolipin

61
Q

Decarboxylation of pyruvate and transfer of the acetyl group to CoA , along with the reduction of NAD+ is catalyzed by ___.

A) pyruvate dehydrogenase

B) pyruvate decarboxylase

C) pyruvate kinase

D) pyruvate carboxylase

A

pyruvate dehydrogenase

62
Q

It is evident from the net equation for the TCA cycle that the primary products of the pathway are the reduced coenzymes _____.

A) oxaloacetate and acetyl-CoA

B) NADH and FADH2

C) water and carbon dioxide

D) ATP and GTP

E) coenzyme A and coenzyme Q

A

NADH and FADH2

63
Q

Two carbons that are removed during the TCA cycle are derived from _____.

A) oxaloacetate

B) NADH

C) acetyl CoA (no)

D) carbon dioxide

E) ATP

A

oxaloacetate

64
Q

During the first two billion years that life existed on Earth, the atmosphere consisted largely of reduced molecules. Which of the following is not a reduced molecule?

A) molecular hydrogen

B) ammonia

C) water

D) carbon dioxide

A

carbon dioxide

65
Q

Mitochondria are the sites of synthesis of the heme groups found in _____.

A) cytochrome c

B) ubiquinone

C) NADH dehydrogenase

D) iron-sulfur proteins

A

cytochrome c

66
Q

The membranes of the mitochondria divide the organelle into two aqueous compartments called the ___ and the ___.

A

matrix, intermembrane space

67
Q

The first step in the TCA cycle is the condensation of the two-carbon acetyl group with a four-carbon _____ to form a six-carbon citrate molecule.

A) oxaloacetate

B) pyruvate

C) alpha-ketoglutarate

D) isocitrate

E) malate

A

oxaloacetate

68
Q

During the TCA cycle, four reactions occur in which a pair of electrons are transferred from a substrate to an electron accepting coenzyme, such as ____.

A) coenzyme Q

B) ATP

C) NAD+ and FAD

D) coenzyme A

E) acetyl-CoA

A

NAD+ and FAD

69
Q

Two carbons that are removed during the TCA cycle are completely oxidized to _____.

A) carbon dioxide

B) ATP

C) NADH

D) oxaloacetate

E) acetyl CoA

A

carbon dioxide

70
Q

NADH molecules formed in the mitochondrial matrix dissociate from their respective dehydrogenases and bind to ____.

A) NADH dehydrogenase

B) succinate dehydrogenase

C) cytochrome bc1

D) cytochrome c oxidase

A

NADH dehydrogenase

71
Q

Which one is a weak reducing agent?

A) H2O of the O2-H2O couple

B) NAD+ of the NAD+-NADH couple

C) O2 of the O2-H2O couple

D) NADH of the NAD+-NADH couple (no)

A

H2O of the O2-H2O couple?

72
Q

With the exception of ____, all of the redox centers within the respiratory chain that accept and donate electrons are prosthetic groups.

A) flavoproteins

B) ubiquinone

C) cytochromes

D) iron sulfur proteins

A

ubiquinone

73
Q

The final electron acceptor of the electron transport chain is _____.

A

oxygen

74
Q

When NADH is the electron donor, electrons pass the respiratory chain by means of ____.

A

complex I

75
Q

Potent respiratory poison, including carbon monoxide, azide and cyanide have their toxic effect by binding to the heme a3 site of _____.

A) cytochrome c

B) ubiquinone

C) complex II

D) cytochrome c oxidase

E) complex I

A

cytochrome c oxidase

76
Q

Substances having high electron-transfer potential, such as NADH, are ___.

A) weak oxidizing agents

B) strong oxidizing agents

C) strong reducing agents

D) weak reducing agents

A

strong reducing agents

77
Q

Which one is a strong oxidizing agent?

A) O2 of the O2-H2O couple

B) NADH of the NAD+-NADH couple

C) H2O of the O2-H2O couple (no)

D) NAD+ of the NAD+-NADH couple

A

O2 of the O2-H2O couple

78
Q

Iron sulfur centers are joined to the protein by linkage to a sulfur atom of a/n ___.

A) carbonyl group

B) amino group

C) cysteine residue

D) alpha-carbon

E) heme group

A

cysteine residue

79
Q

Two components of the electron transport chain are not part on any membrane-spanning complexes. These are ____.

A) ubiquinone and cytochrome c

B) FMN and iron-sulfur proteins

C) NADH dehydrogenase and succinate dehydrogenase

D) cytochrome b and cytochrome c1

A

ubiquinone and cytochrome c

80
Q

The passage of a pair of electrons from NADH to ubiquinone in the respiratory chain is accompanied by movement of roughly four protons from (the) ___ to (the) ___.

A) mitochondria, cytosol

B) NADH, ubiquinone

C) water, oxygen

D) complex I, complex II

E) matrix, intermembrane space

A

matrix, intermembrane space

81
Q

Electron transfer through ____ is not accompanied by proton translocation.

A) complex I

B) complex II

C) complex III

D) complex IV

A

complex II

82
Q

Substances having low electron-transfer potential, such as water, are ___.

A) weak oxidizing agents

B) strong reducing agents

C) weak reducing agents

D) strong oxidizing agents

A

weak reducing agents

83
Q

Which one is a weak oxidizing agent?

A) O2 of the O2-H2O couple

B) NADH of the NAD+-NADH couple (no)

C) H2O of the O2-H2O couple

D) NAD+ of the NAD+-NADH couple

A

H2O of the O2-H2O couple

84
Q

The prosthetic groups of NADH dehydrogenase and succinate dehydrogenase are derived from _____.

A) the electron transport chain

B) pantothenic acid

C) riboflavin

D) iron sulfur proteins

A

riboflavin

85
Q

High energy electrons associated with NADH or FADH2 are transferred through a series of specific electron carriers that constitute the ____ of the inner mitochondrial membrane.

A) glycerol phosphate shuttle

B) matrix

C) intermembrane space

D) electron transport chain

E) inner boundary membrane

A

ETC

86
Q

When FADH2 is the electron donor, electrons are passed directly to ____ in the respiratory chain.

A) ubiquinone

B) complex I

C) complex II (no)

D) cytochrome c oxidase

E) cytochrome c

A

ubiquinone

87
Q

Complex III catalyzes the transfer of electrons from ___ to ___.

A) ubiquinol, cytochrome c

B) NADH, ubiquinone (no)

C) FADH2, ubiquinone

D) cytochrome c, oxygen

A

ubiquinol, cytochrome c

88
Q

Photosynthesis in chloroplasts oxidizes ___ to ___.

A

water, oxygen

89
Q

Absorption of light by by photosystem II leads to the formation of two charged molecules, ________.

A) P700+ and A0-

B) PQB.- and PQB2-

C) NO3- and SO42-

D) NADP+ and H+

E) P680+ and Pheo-

A

P680+ and Pheo-

90
Q

The electron is transferred out of PSI to a small, water-soluble iron-sulfur protein called _____.

A

ferredoxin

91
Q

Organisms that depend on an external source of organic compounds are called ____.

A

heterotrophs

92
Q

Like the outer membrane of a mitochondrion, the outer membrane of a chloroplast envelope contains several different ____.

A) cardiolipins

B) cytochromes

C) porins

D) dehydrogenases

E) ATP synthases

A

porins

93
Q

The ___ is a plot of the relative rate of photosynthesis produced by light of various wavelengths.

A) Z-scheme

B) double reciprocal plot

C) absorption spectrum

D) Lineweaver-Burke plot

E) action spectrum

A

action spectrum

94
Q

The reaction center of photosystem II is a/n _____ referred to as P680.

A) plastoquinone molecule

B) carotenoid pigment

C) oxygen-evolving complex

D) primary electron acceptor

E) chlorophyll dimer

A

chlorophyll dimer

95
Q

The redox potential of the oxidized form of _____ is sufficiently strong to pull tightly held electrons from water, thus splitting the molecule.

A) phylloquinone

B) plastoquinone

C) NADP+

D) plastocyanin

E) P680+

A

P680+

96
Q

Pheo- transfers its electrons to a molecule of ____ bound near the stromal side of the thylakoid membrane.

A) plastocyanin

B) plastoquinone

C) phylloquinone

D) cytochrome c

E) ferredoxin

A

plastoquinone

97
Q

Thylakoid membranes have a high percentage of glycolipids such as ____.

A) monogalactosyl diacylglycerol

B) cholesterol

C) cardiolipin

D) glycosaminoglycans

E) phosphatidylcholine

A

monogalactosyl diacylglycerol

98
Q

Photosynthesis is essentially a redox reaction where ___ is the reducing agent.

A) light

B) oxygen

C) water

D) carbon dioxide

E) glucose

A

water

99
Q

When sunlight strikes a thylakoid membrane, energy is absorbed by ___ and passed to the ___ .

A) photosystem II, photosystem I

B) water, primary electron acceptor

C) P680, P600

D) antenna pigments, reaction centers

E) photosynthetic units, light harvesting complex

A

antenna pigments, reaction centers

100
Q

Photosystem II uses absorbed light energy to generate a proton gradient across the ____.

A) intermembrane space

B) stroma

C) electron transport chain

D) chloroplast envelope

E) thylakoid membrane

A

thylakoid membrane

101
Q

Electrons from cytochrome b6f are passed to a water-soluble, copper-containing peripheral membrane protein called ____.

A) ferredoxin

B) phylloquinone

C) plastocyanin

D) plastoquinone

E) cytochrome c

A

plastocyanin

102
Q

The reduction of NADP+ during the light reactions of photosynthesis removes protons from ____.

A) oxygen

B) ATP

C) carbon dioxide

D) the thylakoid lumen

E) the stroma

A

the stroma

103
Q

In the light reactions, protons are translocated by ____ to form a gradient utilized for ATP synthesis.

A) cytochrome b6f

B) ferredoxin

C) PSI and PSII

D) plastocyanin

E) plastoquinone

A

cytochrome b6f

104
Q

The splitting of water occurs in the _____.

A) mitochondrial matrix

B) thylakoid lumen

C) electron transport chain

D) intermembrane space

E) stroma

A

thylakoid lumen

105
Q

The condensation of RuBP with ___ and the splitting of the resulting six carbon product is carried out by a large multisubunit enzyme known as RuBisCO.

A) carbon dioxide

B) phosphoglycolate

C) 3-phosphoglycerate

D) water

E) oxygen

A

carbon dioxide

106
Q

The enzyme responsible for linkage of carbon dioxide to ___ is phosphoenolpyruvate carboxylase.

A) phosphoglycolate

B) ribulose-1,5-bisphosphate

C) 1,3-bisphosphoglycerate

D) phosphoenolpyruvate

E) glyceraldehyde-3-phosphate

A

phosphoenolpyruvate

107
Q

The product of one organelle may serve as a substrate in another organelle. An example of this is ____.

A) 3-phosphoglycerate

B) phosphoglycolate

C) glyoxylate

D) NADH

E) glycolate

A

glycolate

108
Q

During oxygenic photosynthesis, electrons travel from ____ to ____ by the action of two light absorbing photosystems.

A) the matrix, the intermembrane space

B) the stroma, the thylakoid lumen

C) NADH, oxygen

D) carbon dioxide, glucose

E) water, NADP+

A

water, NADP+

109
Q

Cyclic photophosphorylation is carried out by ____.

A) ATP synthase in the absence of light

B) kinases in the presence of ATP

C) RuBisCo in the presence of oxygen

D) chloroplasts and mitochondria

E) PSI independent of PSII

A

PSI independent of PSII

110
Q

Events occurring in PSI generate a strong reducing agent capable of producing ___ from ___.

A) NADPH, NADP+

B) ATP, a proton gradient

C) carbon dioxide, glucose

D) oxygen, water

E) carbohydrates, light

A

NADPH, NADP+

111
Q

In the Calvin cycle, carboxylation of ___ forms two molecules of 3-phosphoglycerate.

A) ribulose-1,5-bisphosphate

B) 1,3-bisphosphoglycerate

C) glyceraldehyde-3-phosphate

D) phosphoenolpyruvate

E) phosphoglycolate

A

ribulose-1,5-bisphosphate

112
Q

Photorespiration begins when RuBP reacts with oxygen to form 3-PGA and

A) 1,3-bisphosphoglycerate

B) glyceraldehyde-3-phosphate

C) phosphoenolpyruvate

D) ribulose-1,5-bisphosphate

E) phosphoglycolate

A

phosphoglycolate

113
Q

Glycolate produced in the stroma is transferred to the _____.

A) thylakoid lumen

B) mitochondrion

C) cytosol

D) vacuole

E) peroxisome

A

peroxisome

114
Q

Events occurring in PSI generate a strong oxidising agent capable of producing ___ from ___.

A) NADPH, NADP+

B) ATP, a proton gradient

C) carbon dioxide, glucose

D) oxygen, water

E) carbohydrates, light

A

oxygen, water

115
Q

The light reactions of photosynthesis establish a proton gradient across the thylakoid membrane because as a result the removal of protons from ____ and the addition of protons to ____.

A) water, NADP+

B) the stroma, the thylakoid lumen

C) carbon dioxide, glucose

D) the matrix, the intermembrane space

E) NADH, oxygen

A

the stroma, the thylakoid lumen

116
Q

The herbicide paraquat interferes with PSI function by competing with ____ for electron from the PSI reaction center.

A) plastocyanin

B) oxygen

C) ubiquinone

D) ferredoxin

E) water

A

ferredoxin

117
Q

When RuBisCO links carbon dioxide to RuBP, the product rapidly splits into two molecules of _____.

A) 3-phosphoglycerate

B) 1,3-bisphosphoglycerate

C) phosphoglycolate

D) ribulose-1,5-bisphosphate

E) glyceraldehyde-3-phosphate

A

3-phosphoglycerate

118
Q

Photorespiration begins when RuBP reacts with ____ to form 3-PGA and phosphoglycolate.

A) phosphoenolpyruvate

B) oxygen

C) carbon dioxide

D) oxalate

E) water

A

oxygen

119
Q

The light dependent control of chloroplast enzymes is exercised by a small protein called ___ that can occur in either reduced on oxidized form.

A) thioredoxin

B) hemoglobin

C) myoglobin

D) plastocyanin

E) cytochrome c

A

thioredoxin

120
Q

Which one is a strong reducing agent?

A) O2 of the O2-H2O couple

B) NADH of the NAD+-NADH couple

C) H2O of the O2-H2O couple

D) NAD+ of the NAD+-NADH couple

A

NADH of the NAD+-NADH couple

121
Q

The five carbon sugar in ATP is a/n ____.

A

aldose

122
Q

Thylakoid membranes have a high percentage of glycolipids such as ____.

A

monoglycerol?

123
Q

Photorespiration begins when CO2 reacts and forms 3-PGA and ____.

A

phosphoglycerate

124
Q

All amino acids except ____ are symmetric carbons.

A

glycine

125
Q

Prosthetic groups in NADH dehydrogenases ____.

A

FMN

126
Q

Carbon-2 of glycine is called a/n ____.

A

alpha-carbon

127
Q

Which of the following bonds is C the most reduced?

A

C-H

128
Q

___ pathways lead to the synthesis of more complex compounds from simpler starting materials.

A) Exothermic

B) Exergonic

C) Catabolic

D) Signaling

E) Anabolic

A

anabolic

129
Q

In glycolysis, glucose is phosphorylated, isomerized, and the resulting ketose is phosphorylated to form a sugar that can be split into two interconvertible triose phosphates. The interconversion of these triose phosphates is catalyzed by ___.

A) phosphoglucose isomerase

B) triose phosphate isomerase

C) phosphofructokinase

D) aldolase

E) phosphoglyceromutase

A

triose phosphate isomerase

130
Q

In glycolysis, glyceraldehyde-3-P is oxidized to make NADH with uptake or Pi. The product had enough energy to transfer Pi to ADP. NADH in this case is made by _____.

A) alcohol dehydrogenase

B) glyceraldehyde phosphate dehydrogenase

C) NADH dehydrogenase

D) lactate dehydrogenase

E) pyruvate dehydrogenase

A

glyceraldehyde phosphate dehydrogenase

131
Q

Cytochromes a, b and c differ from one another by substitutions within the ___.

A) phosphate group

B) heme group

C) hydrophobic chain

D) iron-sulfur center

E) respiratory chain

A

heme group

132
Q

Events occurring in PSII generate a strong oxidizing agent capable of producing ___ from ___.

A) NADPH, NADP+

B) carbon dioxide, glucose

C) oxygen, water

D) carbohydrates, light

E) ATP, a proton gradient

A

oxygen, water

133
Q

Naturally occurring fatty acids have double bonds in the ___.

A) omega carbon

B) anomeric carbon

C) cis configuration

D) polar head group

E) side chain

A

cis configuration

134
Q

Many enzymes contain nonprotein components called ____ which may be inorganic (metals) or organic (like vitamins).

A

cofactors

135
Q

ATP formation via substrate-level phosphorylation in glycolysis occurs in the reaction catalyzed by ____.

A) glyceraldehyde 3-phosphate dehydrogenase

B) pyruvate kinase

C) alcohol dehydrogenase

D) pyruvate dehydrogenase

E) pyruvate decarboxylase

A

pyruvate kinase

136
Q

In glycolysis, glucose is phosphorylated, isomerized and the resulting isomer is phosphorylated to form a sugar that can be split into two interconvertible triose phosphates. This sugar that can be split into triose phosphates is _____.

A) fructose-6-phosphate

B) fructose-1,6-bisphosphate

C) glucose-6-phosphate

D) glyceraldehyde-3-phosphate

E) dihydroxyacetone phosphate

A

fructose-1,6-bisphosphate

137
Q

Many enzymes contain nonprotein components. An example is succinate dehydrogenase which contains ____.

A) succinate

B) iron

C) NADH

D) FAD

E) oligosaccharides

A

FAD

138
Q

To regenerate NAD+, electrons are transferred from NADH to dihydroxyacetone phosphate to form ______, which shuttles them into the mitochondrion.

A) malate

B) glycerol

C) glycerol 3-phosphate

D) pyruvate

E) aspartate

A

glycerol 3-phosphate

139
Q

Aldotetroses have two asymmetric carbons, and thus can exist in four different configurations. An aldotriose such as ___, has ___ asymmetric carbon(s) and thus __ different configuration(s).

A) glycine, 1, 2

B) dihydroxyacetone, 0, 1

C) ribose 3, 8

D) ribulose, 2, 8

E) glyceraldehyde, 1, 2

A

glyceraldehyde, 1, 2

140
Q

In glycolysis, phosphate is transferred from 3- to 2- position of glycerate so that dehydration will produce a product that has sufficient energy to transfer Pi to ADP. The transfer of Pi to ADP in this case is catalyzed by _____.

A) phosphofructokinase

B) pyruvate kinase

C) hexokinase

D) ATP synthase

E) phosphoglycerate kinase

A

pyruvate kinase

141
Q

One of the products of the oxidation of glyceraldehyde 3-phosphate in glycolysis is _____.

A) NADH

B) glyceraldehyde

C) ATP

D) oxygen

E) glucose

A

NADH

142
Q

Glycosaminoglycans are ____.

A) polysaccharides

B) amino acids

C) triacylglycerols

D) glycoproteins

E) nucleotides

A

polysaccharides

143
Q

Carbon atom is in the fully reduced state in ___.

A) C-O bond

B) methane

C) carbon dioxide

D) C-C bond

E) C-N bond

A

methane

144
Q

The TCA cycle occurs within the ___ of eukaryotic cells.

A) nucleus

B) catabolic pathway

C) anabolic pathway

D) cytoplasm

E) mitochondria

A

mitochondria

145
Q

The conversion of glyceraldehyde 3-phosphate to 3-phosphoglycerate in glycolysis is accompanied by formation of ____.

A) water

B) ATP

C) carbon dioxide

D) oxygen

E) NADH

A

water

146
Q

During the TCA cycle, four reactions occur in which a pair of electrons are transferred from a substrate to an electron accepting coenzyme. One such substrate is _____.

A) NADH

B) ATP

C) succinate

D) dehydrogenases

E) coenzyme A

A

succinate

147
Q

Carbon atom is in the fully oxidized state in ___.

A) carbon dioxide

B) fats

C) methane

D) carbohydrates

E) glucose

A

carbon dioxide

148
Q

In glycolysis, glyceraldehyde-3-P is oxidized to make NADH with uptake or Pi. The product had enough energy to transfer Pi to ADP. This product is _____.

A) phosphoenolpyruvate

B) 3-phosphoglycerate

C) dihydroxyacetone phosphate

D) 1,3-bisphosphoglycerate

E) 2-phosphoglycerate

A

1,3-bisphosphoglycerate

149
Q

Cells are able to regenerate NAD+ by fermentation, which involves the transfer of electrons from NADH to pyruvate, or to a compound derived from pyruvate. This compound derived from pyruvate is _____.

A) acetyl-CoA

B) lactate

C) ethyl alcohol

D) acetaldehyde

A

acetaldehyde