Deck 8: Microbial Metabolism: the Chemical Crossroads of Life

Question 1

The term used to describe all of the chemical reactions within a cell is:

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

Answer 1

D

Question 2

_____ 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

Answer 2

B

Question 3

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

A)anabolism.
B)phosphorylation.
C)fermentation.
D)catabolism.
E)glycolysis.

Answer 3

A

Question 4

Enzymes that catalyze the removal of electrons from one substrate and the addition of electrons to another are called

A)transferases.
B)oxidoreductases.
C)lyases.
D)isomerases.
E)ligases.

Question 5

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

A)in mitochondria.
B)within the cell membrane.
C)in lysosomes.
D)in cytoplasm.
E)outside of the cell.

Question 6

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

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

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)their action may involve minerals.

Question 8

Enzymes that function inside a cell are

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

Question 9

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 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.

Question 12

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.

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)carbohydrate or protein in composition.

Question 14

Enzymes that catalyze the removal of a a functional group and its subsequent attachment to a new substrate are called:

A)transferases.
B)oxidoreductases.
C)isomerases.
D)lyases.
E)ligases.

Question 15

A type of cofactor would be

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

Question 16

The bacterial genus Bacillus can utilize starch as a nutrient by splitting the starch molecule into smaller molecules of glucose,with the addition of water.The enzymes to do this would be classified as:

A)transferases.
B)oxidoreductases.
C)ligases.
D)hydrolases.
E)isomerases.

Question 17

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 18

An apoenzyme is

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

Question 19

Your bacterium is growing on a type of medium called casein agar,which contains milk protein (casein).There is a clear zone around the growth area of the bacterium,showing that it is synthesizing the enzymes needed to catalyze the breakdown of casein.These enzymes are considered:

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

Question 20

All of the following are exoenzymes except

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

Question 21

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 22

Noncompetitive inhibition is best described as

A)substrate binding to DNA,blocking enzyme transcription.
B)end product binding to DNA,blocking enzyme transcription.
C)substrate binding to enzyme in a regulatory site.
D)end product binding to enzyme in noncompetitive site.
E)an anabolic reaction.

Question 23

Glycolysis uses 2 ATP,produces

A)2 ATP,and requires oxygen.
B)2 ATP without oxygen.
C)4 ATP,and requires oxygen.
D)4 ATP all without oxygen.

Question 24

Each of the following are denaturing agents except

A)high temperature.
B)low temperature.
C)high pH.
D)low pH.

Question 25

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 26

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 27

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)positive feedback.

Question 28

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

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

Question 29

Most electron carriers are

A)coenzymes.
B)enzymes.
C)hydrogen.
D)inorganic phosphate.

Question 30

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

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

Question 31

When the product of reaction A becomes the reactant of reaction B,this exemplifies this type of metabolic pathway:

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

Question 32

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 33

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

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

Question 34

FAD,NADP,NAD,and coenzyme A are all carriers of:

A)hydrogens
B)electrons
C)ATP
D)Both hydrogens and electrons are correct.

Question 35

The majority of reduced NAD is produced in

A)glycolysis.
B)the Krebs cycle.
C)the electron transport system.
D)photosynthesis.
E)fermentation.

Question 36

Substrate-level phosphorylation occurs in

A)glycolysis and the electron transport chain.
B)photosynthesis and glycolysis.
C)glycolysis and the Krebs cycle.
D)the Krebs cycle and the electron transport system.
E)the electron transport system only.

Question 37

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 38

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 39

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 40

Each of the following are electron carriers except

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

Question 41

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 42

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 43

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

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

Question 44

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

Question 45

The redox carriers of the electron transport system 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 46

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 47

In which stage of aerobic respiration is water produced?

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

Question 48

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

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

Question 49

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

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

Question 50

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

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

Question 51

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 52

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 53

In which pathway is the most NADH generated?

A)the electron transport system
B)the Krebs cycle
C)glycolysis
D)alcoholic fermentation
E)mixed acid fermentation

Question 54

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)is the same as anaerobic respiration.

Question 55

Which of the following is not a photosynthetic pigment?

A)carotenoid
B)leukophyll
C)phycobilin
D)chlorophyll
E)thylakoid

Question 56

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

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

Question 57

An oxidase detection test can be used to identify certain bacteria because they are missing or lack expression of:

A)cytochrome C oxidase.
B)NAD.
C)mitochondria.
D)ATP synthase.
E)coenzyme Q.

Question 58

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

A)electron transport system
B)the 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

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

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 61

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

Question 62

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 63

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

Question 64

The process of forming glucose from various metabolic intermediates is called

A)glycolysis.
B)amphibolism.
C)phosphorylation.
D)amination.
E)gluconeogenesis.

Question 65

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

Question 66

ATP synthase is a complex enzyme needed for oxidative phosphorylation.

Question 67

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

Question 68

Microbes can utilize only carbohydrates for energy production.

Question 69

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

Question 70

Exoenzymes from pathogens are called virulence factors.

Question 71

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

Question 72

Only yeast produce alcohol as a fermentation product.

Question 73

The principle sites of amphibolic interaction occur during

A)glycolysis and photosynthesis.
B)the Krebs cycle and the electron transport system.
C)glycolysis and the Krebs cycle.
D)fermentation and the Krebs cycle.
E)fermentation and glycolysis.

Question 74

The unknown bacterium that you are testing makes the enzyme phenyalanine deaminase,as indicated by the results of the phenylalanine test that was run.This enzyme facilitates the removal of a(n)____ group from the organic compound so it can be converted into an intermediate compound for the Krebs cycle.

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

Question 75

Which of the following characterize the Calvin cycle?

A)a process that requires light
B)nitrogen is fixed into an organic form
C)produces glucose as an end product
D)produces carbon dioxide and water
E)produces oxygen

Question 76

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

Question 77

Photosynthesis occurs in chloroplasts of prokaryotes.

Question 78

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

Question 79

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 80

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