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

Question 1

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

A)phosphotransferases.
B)oxidoreductases.
C)decarboxylases.
D)aminotransferases.
E)ligases.

Answer 1

C

Question 2

Which of these enzymes is NOT an exoenzyme?

A)ATP synthase
B)streptokinase
C)penicillinase
D)collagenase
E)elastase

Answer 2

A

Question 3

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.

Answer 3

D

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

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

A)phosphotransferases.
B)oxidoreductases.
C)decarboxylases.
D)aminotransferases.
E)ligases.

Question 6

A type of cofactor would be

A)vitamins.
B)metallic ions.
C)active sites.
D)substrates.
E)ribozymes.

Question 7

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 these choices are correct.

Question 8

Enzymes that are secreted by a cell to catalyze hydrolysis reactions are

A)apoenzymes.
B)exoenzymes.
C)constitutive enzymes.
D)regulated enzymes.
E)endoenzymes.

Question 9

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 10

Important components of coenzymes are

A)vitamins.
B)metallic ions.
C)active sites.
D)substrates.
E)ribozymes.

Question 11

What is the final electron acceptor during aerobic respiration?

A)pyruvic acid
B)oxygen
C)nitrate
D)Cytochrome c
E)FAD

Question 12

_____ 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

Question 13

Which term refers to all of the chemical reactions of the cell?

A)catabolism
B)redox reactions
C)phosphorylation
D)metabolism
E)cellular respiration

Question 14

Ribozymes are

A)ribosomes which catalyze reactions.
B)unique to prokaryotes.
C)unique to eukaryotes.
D)catalysts for RNA editing.
E)catalysts for DNA splicing.

Question 15

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 16

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 17

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 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

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

A)substrates.
B)apoenzymes.
C)catalysts.
D)cofactors.

Question 20

Reactants are converted to products by

A)enzymes releasing energy.
B)breaking and forming bonds.
C)enzymes binding to reactants.
D)reactants releasing energy.

Question 21

Each of the following are electron carriers except

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

Question 22

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

A)competitive inhibition.
B)enzyme induction.
C)enzyme repression.
D)feedback inhibition.

Question 23

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 noncompetitive site.
D)product binding to enzyme in noncompetitive site.

Question 24

Most electron carriers are

A)coenzymes.
B)enzymes.
C)hydrogens.
D)inorganic phosphate.
E)All of these choices are correct.

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

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 27

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 28

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, does not require oxygen.
D)uses 2 ATP, produces 2 ATP, does not require oxygen.

Question 29

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

A)linear
B)bidirectional
C)convergent
D)cyclic
E)divergent

Question 30

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 31

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 these choices are correct.

Question 32

FAD, NADP, and NAD are all _____ carriers.

A)hydrogen
B)electron
C)ATP
D)both hydrogen and electron

Question 33

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 34

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

A)ATP.
B)ADP.
C)pyruvic acid.
D)oxygen.
E)NAD.

Question 35

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 36

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 37

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

A)oxidative phosphorylation
B)reductive phosphorylation
C)substrate-level phosphorylation
D)photophosphorylation

Question 38

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 39

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

A)linear.
B)bidirectional.
C)convergent.
D)cyclic.
E)divergent.

Question 40

Enzymes that function inside a cell are

A)apoenzymes.
B)exoenzymes.
C)constitutive enzymes.
D)regulated enzymes.
E)endoenzymes.

Question 41

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

A)pyruvic acid
B)ATP
C)NAD
D)NADH
E)glucose

Question 42

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 43

The majority of reduced NAD is produced in

A)glycolysis.
B)Krebs cycle.
C)the electron transport chain.
D)photosynthesis.

Question 44

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 45

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 46

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

A)cell membrane.
B)mitochondria.
C)chloroplasts.
D)ribosomes.
E)cytoplasm.

Question 47

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.

Question 48

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

A)aerobic respiration.
B)denitrification.
C)nitrification.
D)fermentation.
E)deamination.

Question 49

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

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

Question 50

Which of the following are not photosynthetic pigments?

A)carotenoids
B)leukophylls
C)phycobilins
D)chlorophylls
E)All of these choices are correct.

Question 51

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 52

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

A)NAD molecules.
B)FAD molecules.
C)NADP molecules.
D)the cytochromes.
E)the flavoproteins.

Question 53

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

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

Question 54

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 55

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 56

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 57

In which stage of aerobic respiration is water produced?

A)glycolysis
B)Krebs cycle
C)electron transport system

Question 58

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 59

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 60

Which of the following is not true of anaerobic respiration? v: 05_22_2015_QC_CS-15256

A)involves glycolysis
B)generates some ATP
C)utilizes an electron transport system
D)uses the same final electron acceptors as aerobic respiration

Question 61

ATP synthase is a complex enzyme needed for oxidative phosphorylation.

Question 62

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

Question 63

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

Question 64

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

A)carboxyl
B)amino
C)phosphate
D)hydroxyl

Question 65

Which of the following are characteristics of the Calvin cycle?

A)The Calvin cycle requires light.
B)Nitrogen is fixed into an organic form during the Calvin cycle.
C)The Calvin cycle produces glucose as an end product.
D)The Calvin cycle produces carbon dioxide and water.
E)All of these choices are correct.

Question 66

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 67

Photosynthesis occurs in chloroplasts of prokaryotes.

Question 68

All organisms that are photosynthetic are oxygenic.

Question 69

Only yeast produces alcohol as a fermentation product.

Question 70

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

Question 71

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 72

Many exoenzymes from pathogens are virulence factors.

Question 73

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

Question 74

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

Question 75

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

Question 76

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

A)They occur in the thylakoid membranes.
B)They generates NADPH.
C)They generate glucose from CO₂ and H₂O.
D)Photons cause magnesium to release electrons.
E)ATP is generated by a chemiosmotic mechanism.

Question 77

The process in which organisms integrate catabolic and anabolic pathways to improve cell efficiency is called

A)metabolism.
B)amphibolism.
C)anabolism.
D)catabolism.
E)biosynthesis.

Question 78

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

Question 79

Microbes can utilize only carbohydrates for energy production.

Question 80

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