ch 8 Flashcards
(96 cards)
1
Q
The term used to describe all of the chemical reactions within a cell is \_\_\_\_\_\_. A. catabolism B. redox reactions C. phosphorylation D. metabolism E. cellularrespiration
A
d
2
Q
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. carbohydrateorproteinincomposition.
A
b
3
Q
The formation of peptide bonds between amino acids to build a polypeptide is an example of \_\_\_\_\_\_. A. anabolism B. phosphorylation C. fermentation D. catabolism E. glycolysis
A
a
4
Q
Reactants are converted to products by A. enzymes releasing energy. B. breaking and forming bonds. C. enzymes binding to products. D. reactants always releasing energy.
A
b
5
Q
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.
A
d
6
Q
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
A
c
7
Q
An apoenzyme is \_\_\_\_\_\_. A. partofasimpleenzyme B. alsocalledacoenzyme C. the protein part of a holoenzyme D. often an inorganic metal ion E. anRNAmolecule
A
c
8
Q
A holoenzyme is a combination of a protein and one or more substances called ______.
A. substrates B. apoenzymes C. catalysts
D. cofactors
E. ribozymes
A
d
9
Q
important components of coenzymes are \_\_\_\_\_\_\_. A. vitamins B. metallic ions C. active sites D. substrates
A
a
10
Q
A type of cofactor would be ______.
A. vitamins
B. metallic ions C. active sites D. substrates E. ribozymes
A
b
11
Q
Ribozymes are \_\_\_\_\_\_. A. ribosomes which catalyze reactions B. uniquetoprokaryotes C. unique to eukaryotes D. catalysts for RNA splicing E. catalysts for DNA splicing
A
d
12
Q
Enzymes that are only produced when substrate is present are termed ______.
A. exoenzymes
B. endoenzymes
C. constitutive enzymes D. induced enzymes
E. conjugatedenzymes
A
d
13
Q
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
A
b
14
Q
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
A
d
15
Q
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
A
a
16
Q
The most likely place where an exoenzyme participates in a chemical reaction is \_\_\_\_\_\_. A. inmitochondria B. withinthecellmembrane C. in lysosomes D. in cytoplasm E. outsideofthecell
A
e
17
Q
All of the following are exoenzymes except ______.
A. ATP synthase
B. streptokinase C. penicillinase D. collagenase
A
a
18
Q
During aerobic cellular respiration, the final electron acceptor is \_\_\_\_\_\_. A. pyruvic acid B. oxygen C. nitrate D. cytochrome C E. FAD
A
b
19
Q
Anabolic reactions that involve ligases and release water molecules when bonds are formed are called ______ reactions.
A. reduction
B. condensation C. oxidation
D. transfer
A
b
20
Q
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. endoenzymes
A
b
21
Q
Enzymes that function inside a cell are _
A. apoenzymes
B. exoenzymes
C. constitutive enzymes D. regulated enzymes E. endoenzymes
A
e
22
Q
- Enzymes that are always present, regardless of the amount of substrate, are ______.
A. apoenzymes
B. exoenzymes
C. constitutive enzymes D. regulated enzymes E. endoenzymes
A
c
23
Q
When enzyme action stops due to a buildup of end product that acts as a regulatory molecule, this control is called \_\_\_\_\_\_. A. competitiveinhibition B. enzymeinduction C. enzyme repression D. noncompetitive inhibition
A
d
24
Q
Each of the following are denaturing agents except ______.
A. hightemperature B. low temperature C. high pH
D. low pH
A
b
25
Noncompetitive inhibition is best described as
A. thesubstratebindingtoDNA,blockingenzymetranscription.
B. theendproductbindingtoDNA,blockingenzymetranscription.
C. the substrate binding to enzyme in a regulatory site.
D. the end product binding to enzyme in noncompetitive site.
E .an anabolic reaction.
d
26
Metabolic pathways that regenerate their starting molecule are called _____ pathways. A. linear
B. bidirectional C. convergent D. cyclic
E. divergent
d
27
When the product of reaction A becomes the reactant of reaction B, this exemplifies a _______ metabolic pathway.
A. linear
B. bidirectional C. convergent D. cyclic
E. divergent
a
28
```
Most electron carriers are ______.
A. coenzymes
B. enzymes
C. hydrogen
D. inorganic phosphate
```
a
29
Exergonic reactions
A. includesynthesisoflargecarbohydrates.
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.
c
30
```
In the cell, energy released by electrons is often used to phosphorylate ______.
A. ATP
B. ADP
C. pyruvic acid D. oxygen
E. NAD
```
b
31
```
In addition to electrons, which of the following is also involved in electron transfer?
A. ADP
B. Glucose
C. Carbon
D. Hydrogen
E. Carbondioxide
```
d
32
Each of the following are electron carriers except ______.
| A. NAD B. FAD C. NADP D. FADP
d
33
FAD, NADP, NAD, and coenzyme A are all carriers of ________.
A. hydrogens
B. electrons
C. ATP
D. Both hydrogens and electrons are correct.
d
34
34. The step involving ATP, hexokinase, and the phosphorylation of glucose to glucose-6-phosphate is
A. the final step of the Krebs cycle.
B. thefirstredoxreactionoftheelectrontransportsystem.
C. an example of oxidative phosphorylation.
D. an example of substrate-level phosphorylation.
E. anexampleofphotophosphorylation.
d
35
Which of the following is not a process that regenerates ATP?
A. Oxidativephosphorylation
B. Reductive phosphorylation
C. Substrate-level phosphorylation D. Photophosphorylation
b
36
All
of the following pertain to glycolysis except
A. it occurs without oxygen.
B. it ends with formation of pyruvic acid.
C. it occurs during fermentation.
D. itdegradesglucosetoCO2andH2O.
E. it involves reduction of NAD.
d
37
```
Glycolysis uses 2 ATP and produces
A. 2 ATP only if oxygen is present.
B. 2 A TP without oxygen.
C. 4 ATP only if oxygen is present.
D. 4 ATP without oxygen.
```
d
38
The formation of citric acid from oxaloacetic acid and an acetyl group begins ______.
A. glycolysis
B. theelectrontransportsystem C. the Krebs cycle
D. fermentation
E. oxidativephosphorylation
c
39
Which of the following is not part of the step that occurs between glycolysis and the Krebs cycle?
A. ReductionofNAD+
B. CoenzymeAattachestoanacetylgroup C. Oxidation of pyruvic acid
D. Pyruvic acid accepts electrons from NADH
d
40
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. theelectrontransportsystemonly.
c
41
```
The majority of NADH is produced in ______.
A. glycolysis
B. the Krebs cycle
C. the electron transport system
D. photosynthesis
E. fermentation
```
b
42
In bacterial cells, the electron transport system is located in the ______.
A. cell membrane B. mitochondria C. chloroplasts D. ribosomes
E. cytoplasm
a
43
Each NADH that enters the electron transport system results in the production of _____ ATPs.
A. 2 B. 3 C. 24 D. 36 E. 38
b
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
```
c
45
```
he redox carriers of the electron transport system 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. theflavoproteins
```
d
46
Each FADH2 from the Krebs cycle that enters the electron transport system results in the production of _____ ATP(s)
.A. 1 B. 2 C. 3 D. 4 E. 5
b
47
48. During which phase 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.
a
48
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
e
49
In which stage of aerobic respiration is water produced?
A. Glycolysis
B. The Krebs cycle
C. The electron transport system
c
50
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
e
51
```
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. coenzymeQ
```
a
52
```
What chemical causes death in many eukaryotes because it blocks cytochrome C oxidase?
A. Copper
B. Iron
C. Cyanide
D. Oxygen
E. Carbonmonoxide
```
c
53
Which of the following is not true of anaerobic respiration?
A. Itinvolvesglycolysis.
B. It generates some ATP.
C. It utilizes an electron transport system.
D. It uses the same final electron acceptor as aerobic respiration.
d
54
```
Reduction of nitrogen-oxygen ions and compounds by some bacteria is called ______.
A. aerobic respiration
B. denitrification
C. nitrification
D. fermentation
```
b
55
```
The reactions of fermentation function to produce _______ molecules for further use in glycolysis.
A. pyruvic acid
B. ATP
C. NAD+
D. NADH
E. glucose
```
c
56
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
a
57
Mixed acid fermentation
A. produces butyric acid.
B. occurs in all bacteria.
C. producesseveraldifferentacidsplusCO2andH2gases.
D. is seen in Streptococcus and Lactobacillus.
E. also produces ethanol.
c
58
```
Fermentation ______.
A. requires an organic electron acceptor
B. requiresoxygen
C. only occurs in aerobic organisms
D. is equivalent to aerobic respiration in ATP production
E. is the same as anaerobic respiration
```
a
59
Which of the following is not a photosynthetic pigment?
| A. Carotenoid B. Leukophyll C. Phycobilin D. Chlorophyll
b
60
Which of the following is not true of the light-dependent reactions of photosynthesis?
A. They occur in thylakoid membranes.
B. They generate NADPH.
C. TheygenerateglucosefromCO2andH2O.
D. The photons cause magnesium to release electrons.
E. ATP is generated by a chemiosmotic mechanism.
c
61
62. The unknown bacterium that you are testing makes the enzyme phenyalanine deaminase, as indicated by the results of a phenylalanine test. This enzyme facilitates the removal of a/an ______ 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
b
62
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
b
63
```
The process of forming glucose from various metabolic intermediates is called ______.
A. glycolysis
B. amphibolism
C. phosphorylation D. amination
E. gluconeogenesis
```
e
64
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. fermentationandglycolysis
c
65
```
Intermediates from the Krebs cycle can be converted to amino acids by the process of ______.
A. amination
B. deamination
C. phosphorylationD. beta oxidation
E. gluconeogenesis
```
a
66
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
c
67
ATP molecules are catalysts that lower the activation energy needed to initiate a reaction.
t/f
f
68
Building block molecules for biosynthetic pathways come from the cell's catabolic pathways and from the environment.
t/f
t
69
Hydrolysis reactions are catabolic reactions that use water to split the reactant into smaller subunits.
t/f
t
70
Exoenzymes from pathogens are called virulence factors
| t/f
t
71
The best way to control a metabolic pathway is to control the fastest enzyme in the series.
t/f
f
72
73. Denaturing an apoenzyme will destroy the three-dimensional shape of the protein, making it nonfunctional
t/f
t
73
ATP is composed of deoxyribose, adenine, and three phosphate groups.
t/f
f
74
Glyceraldehyde-3-phosphate is an intermediary of glycolysis that can also be utilized in biosynthetic pathways.
t/f
t
75
ATP synthase is a complex enzyme needed for oxidative phosphorylation.
t/f
t
76
All aerobic bacterial species have identical electron acceptors in their electron transport systems.
t/f
f
77
Only yeast produce alcohol as a fermentation product.
| t/f
t
78
Oxygen-containing ions are used by some bacteria in their electron transport system.
t/f
t
79
Microbes can utilize only carbohydrates for energy production.
t/f
f
80
81. Photosynthesis occurs in chloroplasts of prokaryotes.
| t/f
f
81
All organisms that are photosynthetic are oxygenic.
| t/f
f
82
Recently discovered bacteria that inhabit the ocean floor undergo photosynthesis using light from chemical reactions, the breaking of mineral crystals, or from bubble formation.
t/f
t
83
Sulfa drugs like Bactrim, given for bacterial infections, inhibit bacteria by blocking folic acid synthesis. The precursor molecule of folic acid is para-amino benzoic acid (PABA). Interestingly, PABA has a structure very similar to a sulfa drug. If a sulfa drug is present, the bacterial enzyme will bind the sulfa drug because of structural similarity. This is an example of ______.
A. enzymeinduction
B. enzymerepression
C. noncompetitive inhibition D. competitive inhibition
E. cataboliterepression
d
84
When comparing fermentation and anaerobic respiration, which statement would be true?
A. Fermentation and anaerobic respiration are the same.
B. Fermentation produces carbon dioxide, whereas anaerobic respiration does not.
C. Anaerobic respiration and fermentation both employ the electron transport system.
D. Both anaerobic respiration and fermentation use phosphorylation to make ATP.
d
85
The space between the cell membrane and the cell wall is important during aerobic respiration. Why?
A. Hydrogen ions are transported out into the space to set up a hydrogen gradient.
B. Cytochrome electron carriers are located in the space.
C. Oxygen combines with electrons in that space to form water.
D. Pyruvate is transported into the space to be converted into acetyl coenzyme A to enter the Krebs cycle.
a
86
Below is a metabolic pathway having 3 chemical reactions and 3 enzymes. Enzyme 1 has 2 binding sites-- 1 for the substrate A and another for the end product D. As the pathway proceeds, the end product in higher quantities will react with enzyme 1, blocking the enzyme's binding to the substrate. Which statement is true about this pathway?
enz1 enz2 enz3
Substrate A --> B --> C --> D end product
A. This is a case of noncompetitive inhibition.
B. As a result of the inhibition of the enzyme, there will eventually be less substrate converted to the end
product D.
C. Enzyme 1 has an active site and a regulatory site.
D. All of the choices are correct.
d
87
Which of the following metabolic system descriptions is mismatched?
A. Cyclic - the starting molecule is regenerated to initiate another turn
B. Convergent - a linear pathway branches into two or more alternative processes
C. Linear - the product of enzyme A becomes the substrate for enzyme B
D. Divergent - one or more branches deviate from a linear path
b
88
Oxidoreductase apoenzymes utilize a coenzyme to function. The NAD+ and FAD coenzymes
A. carry only electrons between molecules.
B. are oxidized when they remove electrons from the substrate.
C. are reduced when they remove electrons from the substrate.
D. are reduced when they add electrons to the substrate.
c
89
```
Often the mnemonic device "OIL RIG" is used to remember the principles of redox reactions. Oxidation Is Loss and Reduction Is Gain of what?
A. Electrons only
B. Hydrogenonly
C. Oxygen only
D. Electrons and hydrogen
E. Oxygenandelectrons
```
d
90
Which of the following statements is false regarding amphibolic pathways?
A. Metabolic pathways are amphibolic, that is, catabolism and anabolism are intertwined in order to conserve energy in the cell.
B Glucose is broken down in glycolysis; however, not all of the intermediates in the pathway are utilized as an . energy source. Many leave the pathway to serve as precursors for complex molecules.
C. Glyceraldehyde-3-phosphate is used as a precursor for amino acid, lipid, and carbohydrate synthesis.
D. All organisms use metabolic pathways to synthesize the 20 amino acids necessary for protein
synthesis using precursors from catabolic processes.
E.Glucose is broken down during glycolysis to pyruvate; however, when glucose is in short supply, pyruvate is
used as a precursor in the process of gluconeogenesis.
d
91
The relationship between the light-dependent and light-independent reactions in photosynthesis is that
A.the ATP made during the light-dependent reactions is used for the growth and development of the cell and the ATP from the oxidation of glucose drives the light reactions.
B. the light-independent reactions are driven by the ATP and NADPH generated from the light reactions.
C. the energy stored in the glucose made during the Calvin cycle is used to drive the light reactions.
D. the light-dependent and light-independent reactions both take place within the membranes of bacterial
cells or thylakoid membranes of chloroplasts.
b
92
During the Calvin cycle, carbon dioxide gas is fixed into a solid, organic form; this is an endergonic process driven by ATP generated from aerobic respiration.
t/f
f
93
```
Which of the following processes is endergonic?
A. Beta oxidation of fatty acids
B. Carbon fixation
C. The oxidation of glucose
D. Deamination
E. Burningwood
```
b
94
```
he light-harvesting units in the thylakoid membranes are the ______.
A. A TP synthases
B. electrons
C. ATP molecules
D. photosystems
E. grana
```
d
95
```
What process is described here? A concentration gradient of H+ ions is created in the periplasmic space by actively transporting the ions across the membrane using the energy liberated when carrier molecules are
oxidized. When the H+ ions pass through ATPase, enough energy is generated to add phosphate groups onto
ADP molecules.
A. Fermentation
B. TheCalvincycle
C. Substrate-level phosphorylation
D. Oxidative phosphorylation
E. Deamination
```
d
96
Glycolysis and the Krebs cycle yield 10 molecules of NADH per molecule of glucose. How many molecules of ATP will be made from them in the electron transport system?
A. 10 B. 38 C. 36 D. 2 E. 30
e
