1. Glucose contains more energy than the products of its metabolism, CO2 and H2O.

True False

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2. All chemicals have the same amount of potential energy.

True False ___

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 ___

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 ___

6. The entropy of the universe is decreasing.

True False ___

7. About ten times as many people can be sustained on a diet of vegetables and grain as can be sustained on a diet of meat.

True False

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8. 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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9. 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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10. The amount of energy contained in one population that is taken up by the next population is about _____.

A. 100% B. 90% C. 50% D. 10% ___

11. 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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12. The use of fossil fuels by our society has increased the efficiency of food production.

True False ___

13. Reactions which require an input of energy ___________.

A. are exergonic B. are endergonic C. will never occur

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14. 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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15. If the change in free energy in both directions of a reaction is just about zero, the reaction is reversible.

True False

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16. Once ATP breakdown is coupled with muscle contraction, the overall process becomes exergonic and muscle contractionoccurs.

True False

___

17. The breakdown of ATP to ADP + P is a _____ reaction.

A. exergonic B. endergonic C. coupled

___

18. 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 ___

19. All of the energy in glucose is transformed into ATP by the mitochondria.

True False ___

20. The "energy currency" of the cell is _______.

A. ATP B. glucose C. ADP + P D. starch

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21. ATP is a _____.

A. protein B. lipid C. nucleotide D. polysaccharide

___

22. Active transport could be described as _____.

A. exergonic B. endergonic ___

23. The nitrogen base in ATP is _____________.

A. guanine B. thymine C. uracil D. adenosine ___

24. When ATP becomes ADP + P, just enough energy is released to make cilia beat so little energy is wasted.

True False

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25. In a metabolic pathway, reactions occur haphazardly and have nothing to do with one another.

True False ___

26. Enzymes are _____.

A. nucleotides B. proteins C. lipids D. monosaccharides

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27. 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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28. Enzymes lower the energy of activation of reactions so they can occur at body temperature.

True False

___

29. 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 ___

30. Which of the following is NOT an enzyme?

A. DNA polymerase B. carbonic anhydrase C. sodium bicarbonate D. helicase

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31. 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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32. Enzymes bind to their substrates at any place on the substrate.

True False ___

33. A very high fever (105°) is dangerous because enzymes can become denatured.

True False

___

34. 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 ___

35. 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 thatdigests proteins to peptides in the stomach, when it moves into the small intestine?

A. Pepsin will continue to function efficiently. B. Pepsin will become denatured. C. Pepsin's shape will change. D. both B and C ___

36. 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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37. When a molecule binds to an enzyme at an allosteric site, _____ inhibition occurs.

A. competitive B. noncompetitive ___

38. 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 ___

39. Symptoms of a vitamin deficiency may actually be the result of a deficiency of a coenzyme needed to assist enzymeactivity.

True False

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40. The activity of almost every enzyme in a cell is regulated by feedback inhibition.

True False

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