Deck 8: An Introduction to Microbial Metabolism: the Chemical Crossroads of Life

Question 1

Enzymes that can function at boiling water temperatures or other harsh conditions would be termed

A)Denatured
B)Ribozymes
C)Abzymes
D)Exoenzymes
E)Extremozymes

Answer 1

E

Question 2

Ribozymes are

A)Ribosomes which catalyze reactions
B)Unique to prokaryotes
C)Unique to eukaryotes
D)Catalysts for RNA splicing
E)Catalysts for DNA splicing

Answer 2

D

Question 3

Enzymes that catalyze moving a phosphate from one substrate to another are called

A)Phosphotransferases
B)Oxidoreductases
C)Decarboxylases
D)Aminotransferases
E)Ligases

Answer 3

A

Question 4

An apoenzyme

A)Is part of a simple enzyme
B)Is also called a coenzyme
C)Is the protein part of a holoenzyme
D)Is often an inorganic metal ion
E)Is an RNA molecule

Question 5

_____ reactions are anabolic reactions involving ligases for synthesis and the release of one water molecule for each bond formed.

A)Reduction
B)Condensation
C)Oxidation
D)Transfer
E)None of the choices are correct

Question 6

Enzymes that catalyze removal of carbon dioxide from a substrate are called

A)Phosphotransferases
B)Oxidoreductases
C)Decarboxylases
D)Aminotransferases
E)Ligases

Question 7

Each of the following are true of enzymes except

A)They can be used over and over
B)They may or may not require cofactors
C)Their active site is specific to the substrate
D)They increase the activation energy of a reaction
E)All of the choices are true of enzymes

Question 8

All of the following are exoenzymes except

A)ATP synthase
B)Streptokinase
C)Penicillinase
D)Collagenase
E)Elastase

Question 9

During aerobic cellular respiration, the final electron acceptor is

A)Pyruvic acid
B)Oxygen
C)Nitrate
D)Cytochrome c
E)FAD

Question 10

Important components of coenzymes are

A)Vitamins
B)Metallic ions
C)Active sites
D)Substrates
E)Ribozymes

Question 11

Reactants are converted to products by

A)Enzymes releasing energy
B)Breaking and forming bonds
C)Enzymes binding to reactants
D)Reactants releasing energy
E)None of the choices are correct

Question 12

Enzymes that catalyze removing electrons from one substrate and adding electrons to another are called

A)Phosphotransferases
B)Oxidoreductases
C)Decarboxylases
D)Aminotransferases
E)Ligases

Question 13

Enzymes are

A)Broken down in reactions that require energy input
B)Proteins that function as catalysts
C)Used up in chemical reactions
D)Not needed for catabolic reactions
E)All of the choices are correct

Question 14

A type of cofactor would be

A)Vitamins
B)Metallic ions
C)Active sites
D)Substrates
E)Ribozymes

Question 15

A holoenzyme is a combination of a protein and one or more substances called

A)Substrates
B)Apoenzymes
C)Catalysts
D)Cofactors
E)None of the choices are correct

Question 16

Formation of peptide bonds between amino acids to build a polypeptide would be called

A)Anabolism
B)Phosphorylation
C)Fermentation
D)Exergonic
E)Glycolysis

Question 17

The most likely place where an exoenzyme participates in a chemical reaction is

A)Mitochondria
B)Within the cell membrane
C)Lysosomes
D)Cytoplasm
E)Outside of the cell

Question 18

Enzymes that are only produced when substrate is present are termed

A)Exoenzymes
B)Endoenzymes
C)Constitutive enzymes
D)Induced enzymes
E)Conjugated enzymes

Question 19

All of the chemical reactions of the cell are called

A)Catabolism
B)Redox reactions
C)Phosphorylation
D)Metabolism
E)Cellular respiration

Question 20

The cell's metabolic reactions involve the participation of _____ that lower the activation energy needed for the initiation of a reaction.

A)Cofactors
B)Vitamins
C)Enzymes
D)ATP
E)Coenzymes

Question 21

The step involving ATP, hexokinase and the phosphorylation of glucose to glucose-6-phosphate is

A)The final step of the Krebs cycle
B)The first redox reaction of the electron transport system
C)An example of oxidative phosphorylation
D)An example of substrate-level phosphorylation
E)An example of photophosphorylation

Question 22

Which of the following is not involved in the step that occurs between glycolysis and the Krebs cycle?

A)Reduction of NAD
B)Decarboxylation of pyruvic acid
C)Coenzyme A attaches to an acetyl group
D)Dehydrogenation of pyruvic acid
E)Pyruvic acid accepts electrons from NADH

Question 23

Enzymes that function inside a cell are

A)Apoenzymes
B)Exoenzymes
C)Constitutive enzymes
D)Regulated enzymes
E)Endoenzymes

Question 24

The formation of citric acid from oxaloacetic acid and an acetyl group begins

A)Glycolysis
B)The electron transport system
C)The Krebs cycle
D)Fermentation
E)Oxidative phosphorylation

Question 25

In addition to electrons, which of the following is also involved in electron transfer?

A)ADP
B)Glucose
C)Carbon
D)Hydrogen
E)Carbon dioxide

Question 26

When enzyme action stops due to a buildup of end product, this control is called

A)Negative feedback
B)Competitive inhibition
C)Enzyme induction
D)Enzyme repression
E)Feedback inhibition

Question 27

FAD, NADP, NAD and coenzyme A are all _____ carriers.

A)Hydrogen
B)Electron
C)ATP
D)Both hydrogen and electron
E)None of the choices are correct

Question 28

All of the following pertain to glycolysis except

A)Occurs without oxygen
B)Ends with formation of pyruvic acid
C)Occurs during fermentation
D)Degrades glucose to CO₂ and H₂O
E)Involves reduction of NAD

Question 29

Most electron carriers are

A)Coenzymes
B)Enzymes
C)Hydrogens
D)Inorganic phosphate
E)All of the choices are correct

Question 30

Feedback inhibition is best described as

A)Substrate binding to DNA, blocking enzyme transcription
B)Product binding to DNA, blocking enzyme transcription
C)Substrate binding to enzyme in non-competitive site
D)Product binding to enzyme in non-competitive site
E)None of the choices are correct

Question 31

Enzymes that are secreted by a cell to hydrolyze reactions are

A)Apoenzymes
B)Exoenzymes
C)Constitutive enzymes
D)Regulated enzymes
E)Endoenzymes

Question 32

Metabolic pathways that regenerate their starting point are called _____ pathways.

A)Linear
B)Bi-directional
C)Convergent
D)Cyclic
E)Divergent

Question 33

Each of the following are electron carriers except

A)NAD
B)FAD
C)NADP
D)FADP
E)Coenzyme A

Question 34

Each of the following are denaturing agents except

A)High temperature
B)Low temperature
C)High pH
D)Low pH
E)All of the choices are correct

Question 35

Enzymes that are always present, regardless of the amount of substrate are

A)Apoenzymes
B)Axoenzymes
C)Constitutive enzymes
D)Regulated enzymes
E)Endoenzymes

Question 36

When the product of reaction A becomes the reactant of reaction B, the metabolic pathway is

A)Linear
B)Bi-directional
C)Convergent
D)Cyclic
E)Divergent

Question 37

Exergonic reactions

A)Include synthesis of large carbohydrates
B)Only occur in heterotrophs
C)Occur during aerobic cellular respiration
D)Do not occur in anaerobic cellular respiration
E)Occur when ADP binds to inorganic phosphate to form ATP

Question 38

Glycolysis

A)Uses 2 ATP, produces 2 ATP and requires oxygen
B)Uses 2 ATP, produces 4 ATP and requires oxygen
C)Uses 2 ATP, produces 4 ATP, without oxygen
D)Uses 2 ATP, produces 2 ATP, without oxygen
E)None of the choices are correct

Question 39

In the cell, energy released by electrons is often used to phosphorylate

A)ATP
B)ADP
C)Pyruvic acid
D)Oxygen
E)NAD

Question 40

Which of the following is not a process that regenerates ATP?

A)Oxidative phosphorylation
B)Reductive phosphorylation
C)Substrate level phosphorylation
D)Photophosphorylation
E)Autophosphorylation

Question 41

Each FADH₂ from the Krebs cycle enters the electron transport system and gives rise to _____ ATP's.

A)1
B)2
C)3
D)4
E)5

Question 42

As the electron transport carriers shuttle electrons, they actively pump _____ into the outer membrane compartment setting up a concentration gradient called the proton motive force.

A)ATP
B)Phosphate
C)Hydrogen ions
D)Oxygen
E)NADH

Question 43

An oxidase detection test can be used to identify certain bacteria because they lack

A)cytochrome c oxidase
B)NAD
C)Mitochondria
D)ATP synthase
E)Coenzyme Q

Question 44

What chemical causes death in many eukaryotes because it blocks cytochrome c oxidase?

A)Copper
B)Iron
C)Cyanide
D)Oxygen
E)Carbon monoxide

Question 45

Substrate level phosphorylation occurs in

A)Glycolysis and electron transport chain
B)Photosynthesis and glycolysis
C)Glycolysis and Krebs cycle
D)Krebs cycle and electron transport chain
E)All of the choices are correct

Question 46

Fermentation

A)Requires an organic electron acceptor
B)Requires oxygen
C)Only occurs in aerobic organisms
D)Is equivalent to aerobic respiration in ATP production
E)None of the choices are correct

Question 47

Reduction of nitrogen-oxygen ions and compounds by some bacteria is called

A)Aerobic respiration
B)Denitrification
C)Nitrification
D)Fermentation
E)Deamination

Question 48

Which of the following is not true of anaerobic respiration?

A)Is also called fermentation
B)Involves glycolysis
C)Generates some ATP
D)Utilizes an electron transport system
E)Uses the same final electron acceptors as aerobic respiration

Question 49

Mixed acid fermentation

A)Produces butyric acid
B)Occurs in all bacteria
C)Produces several different acids plus CO₂ and H₂ gases
D)Is seen in Streptococcus and Lactobacillus
E)Also produces ethanol

Question 50

When glucose is broken down by glycolysis during bacterial fermentation, what is the net production of ATP?

A)2 ATP
B)3 ATP
C)24 ATP
D)36 ATP
E)38 ATP

Question 51

In which pathway is the most NADH generated?

A)Electron transport system
B)Krebs cycle
C)Glycolysis
D)Alcoholic fermentation
E)Mixed acid fermentation

Question 52

How many carbon dioxide molecules are produced by the complete aerobic breakdown of one glucose molecule?

A)2
B)3
C)4
D)5
E)6

Question 53

The redox carriers of the electron transport chain that have a tightly bound metal atom responsible for accepting and donating electrons are

A)NAD
B)FAD
C)NADP
D)The cytochromes
E)The flavoproteins

Question 54

In which stage of aerobic respiration is water produced?

A)Glycolysis
B)Krebs cycle
C)Electron transport system

Question 55

The majority of reduced NAD is produced in

A)Glycolysis
B)Krebs cycle
C)Electron transport chain
D)Photosynthesis
E)None of the choices are correct

Question 56

In bacterial cells, the electron transport system is located in the

A)Cell membrane
B)Mitochondria
C)Chloroplasts
D)Ribosomes
E)Cytoplasm

Question 57

During which of the phases of cellular respiration is the majority of ATP formed?

A)Electron transport
B)Krebs cycle
C)Glycolysis
D)Processing of pyruvic acid for the Krebs cycle
E)All phases produce the same number of ATP molecules

Question 58

In bacterial cells, when glucose is completely oxidized by all the pathways of aerobic cellular respiration, what is the maximum number of ATP generated?

A)2 ATP
B)3 ATP
C)24 ATP
D)36 ATP
E)38 ATP

Question 59

The reactions of fermentation function to produce _____ molecules for use in glycolysis.

A)Pyruvic acid
B)ATP
C)NAD
D)NADH
E)Glucose

Question 60

Each NADH that enters the electron transport system gives rise to _____ ATP.

A)2
B)3
C)24
D)36
E)38

Question 61

Denaturing an apoenzyme will destroy the three-dimensional shape of the protein, making it nonfunctional.

Question 62

ATP is composed of deoxyribose, adenine and 3 phosphate groups.

Question 63

The process of forming glucose from various metabolic intermediates is called

A)Glycolysis
B)Amphibolism
C)Phosphorylation
D)Amination
E)Gluconeogenesis

Question 64

Only yeast produces alcohol as a fermentation product.

Question 65

Glyceraldehyde-3-phosphate is an intermediary of glycolysis that can also be utilized in biosynthetic pathways.

Question 66

Intermediates from the Krebs cycle can be converted to amino acids by the process of

A)Amination
B)Deamination
C)Phosphorylation
D)Beta oxidation
E)Gluconeogenesis

Question 67

Oxygen-containing ions are used by some bacteria in a cytochrome-like system.

Question 68

All aerobic bacterial species have identical electron acceptors in their electron transport systems.

Question 69

The property of organisms to integrate catabolic and anabolic pathways to improve cell efficiency is called

A)Metabolism
B)Amphibolism
C)Anabolism
D)Catabolism
E)Biosynthesis

Question 70

The principle sites of amphibolic interaction occur during

A)Glycolysis and photosynthesis
B)Krebs cycle and electron transport system
C)Glycolysis and Krebs cycle
D)Fermentation and Krebs cycle
E)Fermentation and glycolysis

Question 71

Building block molecules for biosynthetic pathways come from the cell's catabolic pathways and from the environment.

Question 72

The best way to control a metabolic pathway is to control the fastest enzyme in the series.

Question 73

Exoenzymes from pathogens are called virulence factors.

Question 74

Which of the following are not photosynthetic pigments?

A)Carotenoids
B)Leukophylls
C)Phycobilins
D)Chlorophylls
E)All of the above are photosynthetic pigments

Question 75

Hydrolysis reactions are catabolic reactions that use water to split the reactant into smaller subunits.

Question 76

ATP molecules are catalysts that lower the activation energy needed to initiate a reaction.

Question 77

Amination is the addition of a(n) _____ group to a carbon skeleton.

A)Carboxyl
B)Amino
C)Phosphate
D)Hydroxyl
E)None of the choices are correct

Question 78

Which of the following is not true of the light-dependent reactions of photosynthesis?

A)Occurs in thylakoid membranes
B)Generates NADPH
C)Generates glucose from CO₂ and H₂O
D)Photons cause magnesium to release electrons
E)ATP is generated by a chemiosmotic mechanism

Question 79

ATP synthase is a complex enzyme needed for oxidative phosphorylation.

Question 80

Which of the following are characteristics of the Calvin cycle?

A)A process the requires light
B)Nitrogen is fixed into an organic form
C)Produces glucose as an end product
D)Produces carbon dioxide and water
E)All of these