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1 | |
Glucose contains more energy than the products of its metabolism, CO2 and H2O. |
| | A) | True |
| | B) | False |
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2 | |
All chemicals have the same amount of potential energy. |
| | A) | True |
| | B) | False |
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3 | |
Organisms require a constant supply of energy because _____. |
| | A) | they cannot create energy |
| | B) | when they transform energy some is lost as heat |
| | C) | maintenance of their cellular organization requires a lot of work |
| | D) | all of the above |
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4 | |
Which of the following is an example of potential energy? |
| | A) | a big piece of chocolate cake |
| | B) | someone running a marathon |
| | C) | a fish swimming upstream |
| | D) | a leaf unfolding |
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5 | |
Energy is needed by organisms to _____________. |
| | A) | respond to stimuli |
| | B) | reproduce |
| | C) | grow |
| | D) | all of the above |
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6 | |
The entropy of the universe is decreasing. |
| | A) | True |
| | B) | False |
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7 | |
Energy that is doing work is _____. |
| | A) | called potential energy |
| | B) | stored in the bonds of glucose |
| | C) | called kinetic energy |
| | D) | both A and B |
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8 | |
Which of the following statements about energy is FALSE? |
| | A) | Energy can't be created and it can't be destroyed. |
| | B) | Chemical energy in our food can be transformed into energy needed for muscle contractions. |
| | C) | When energy is transformed, all of it is available to do work. |
| | D) | A battery you just bought at the store has potential energy. |
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9 | |
Energy is constantly supplied to ecosystems by _____. |
| | A) | radioactive elements |
| | B) | the sun |
| | C) | heat from the ocean's thermal vents |
| | D) | gravity |
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10 | |
Reactions which require an input of energy ___________. |
| | A) | are exergonic |
| | B) | are endergonic |
| | C) | will never occur |
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11 | |
In the reaction A + B --> C + D, the reactant(s) is/are ______________. |
| | A) | only A |
| | B) | A and B |
| | C) | only D |
| | D) | C + D |
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12 | |
If the change in free energy in both directions of a reaction is just about zero, the reaction is reversible. |
| | A) | True |
| | B) | False |
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13 | |
Once ATP breakdown is coupled with muscle contraction, the overall process becomes exergonic and muscle contraction occurs. |
| | A) | True |
| | B) | False |
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14 | |
The breakdown of ATP to ADP + P is a _____ reaction. |
| | A) | exergonic |
| | B) | endergonic |
| | C) | coupled |
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15 | |
Which of the following is an example of an endergonic reaction? |
| | A) | muscle contraction |
| | B) | protein synthesis |
| | C) | nerve conduction |
| | D) | all of the above |
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16 | |
All of the energy in glucose is transformed into ATP by the mitochondria. |
| | A) | True |
| | B) | False |
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17 | |
The "energy currency" of the cell is _______. |
| | A) | ATP |
| | B) | glucose |
| | C) | ADP + P |
| | D) | starch |
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18 | |
ATP is a _____. |
| | A) | protein |
| | B) | lipid |
| | C) | nucleotide |
| | D) | polysaccharide |
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19 | |
Active transport could be described as _____. |
| | A) | exergonic |
| | B) | endergonic |
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20 | |
The nitrogen base in ATP is _____________. |
| | A) | guanine |
| | B) | thymine |
| | C) | uracil |
| | D) | adenosine |
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21 | |
When ATP becomes ADP + P, just enough energy is released to make cilia beat so little energy is wasted. |
| | A) | True |
| | B) | False |
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22 | |
In a metabolic pathway, reactions occur haphazardly and have nothing to do with one another. |
| | A) | True |
| | B) | False |
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23 | |
Enzymes are _____. |
| | A) | nucleotides |
| | B) | proteins |
| | C) | lipids |
| | D) | monosaccharides |
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24 | |
Enzymes _____. |
| | A) | slow down chemical reactions |
| | B) | increase the energy of activation |
| | C) | bring together specific molecules and causes them to react with each other |
| | D) | all of the above |
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25 | |
Enzymes lower the energy of activation of reactions so they can occur at body temperature. |
| | A) | True |
| | B) | False |
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26 | |
In the metabolic pathway below, which letter does NOT represent a reactant?
A --> B --> C --> D --> E |
| | A) | B |
| | B) | C |
| | C) | D |
| | D) | E |
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27 | |
Which of the following is NOT an enzyme? |
| | A) | DNA polymerase |
| | B) | carbonic anhydrase |
| | C) | sodium bicarbonate |
| | D) | helicase |
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28 | |
Which of the following is a INCORRECT association of enzyme and substrate? |
| | A) | maltose - maltase |
| | B) | lipid - lipase |
| | C) | sucrose - lactase |
| | D) | acetylcholine - acetylcholinesterase |
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29 | |
Enzymes bind to their substrates at any place on the substrate. |
| | A) | True |
| | B) | False |
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30 | |
A very high fever (105°) is dangerous because enzymes can become denatured. |
| | A) | True |
| | B) | False |
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31 | |
Denaturation _____. |
| | A) | changes the shape of the enzyme |
| | B) | prevents the enzyme from binding with its substrate molecules efficiently |
| | C) | occurs at temperatures above a certain point |
| | D) | all of the above |
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32 | |
The pH in the stomach is about 2 and the pH in the small intestine is about 8. What will happen to pepsin, an enzyme that digests protei |
| | A) | ns to peptides in the stomach, when it moves into the small intestine? |
| | B) | Pepsin will continue to function efficiently. |
| | C) | Pepsin will become denatured. |
| | D) | Pepsin's shape will change. |
| | E) | both B and C |
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33 | |
The speed of a reaction that involves an enzyme increases as |
| | A) | temperature decreases |
| | B) | pH becomes less than optimal |
| | C) | substrate concentration increases |
| | D) | all of the above |
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34 | |
When a molecule binds to an enzyme at an allosteric site, _____ inhibition occurs. |
| | A) | competitive |
| | B) | noncompetitive |
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35 | |
Enzyme activity can be inhibited by _____. |
| | A) | a molecule that blocks its active site |
| | B) | changes in pH |
| | C) | poisons such as cyanide |
| | D) | all of the above |
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36 | |
Symptoms of a vitamin deficiency may actually be the result of a deficiency of a coenzyme needed to assist enzyme activity. |
| | A) | True |
| | B) | False |
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37 | |
The activity of almost every enzyme in a cell is regulated by feedback inhibition. |
| | A) | True |
| | B) | False |
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38 | |
In the reaction (NADP+ + 2e- + H+ --> NADPH) NADP+ is _____. |
| | A) | oxidized |
| | B) | reduced |
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39 | |
During cellular respiration, glucose loses hydrogen ions so it is _____. |
| | A) | oxidized |
| | B) | reduced |
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40 | |
Energy is released during cellular respiration so it is best described as _____. |
| | A) | endergonic |
| | B) | exergonic |
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41 | |
Both photosynthesis and cellular respiration make use of an electron carrier and an electron transport system. |
| | A) | True |
| | B) | False |
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42 | |
The coenzyme ____ accepts electrons during cellular respiration. |
| | A) | NAD+ |
| | B) | ATP |
| | C) | niacin |
| | D) | zinc |
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43 | |
ATP production in the electron transport system depends on _____. |
| | A) | the establishment of an electrochemical gradient |
| | B) | carrier proteins |
| | C) | ATP synthase |
| | D) | all of the above |
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44 | |
Electron transport systems used to make ATP are located in the _____. |
| | A) | chloroplasts |
| | B) | nucleus |
| | C) | mitochondria |
| | D) | both A and C |
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45 | |
Without __________ organisms, life as we know it could not exist. |
| | A) | photosynthetic |
| | B) | carnivorous |
| | C) | herbivorous |
| | D) | parasitic |
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46 | |
Cells that do a lot of active transport have many _____. |
| | A) | mitochondria |
| | B) | nuclei |
| | C) | chloroplasts |
| | D) | plasmids |
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47 | |
The exact mechanism of ATP synthesis has been known about for hundreds of years. |
| | A) | True |
| | B) | False |
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48 | |
Oxidation and reduction reactions always occur at the same time because one molecule accepts the electrons given up by another molecule. |
| | A) | True |
| | B) | False |
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49 | |
The sodium-potassium pump, associated with muscle and nerve cells, moves Na+ to the outside of the cell and K+ to the inside of the cell. |
| | A) | True |
| | B) | False |
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50 | |
The functioning of the sodium-potassium pump depends upon the availability of ATP. |
| | A) | True |
| | B) | False |
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