Exam Questions The Energy Of Life Chapter.4 4th Edition

Chapter 04

The Energy of Life

Multiple Choice Questions

1. The metabolic rate of individuals is influenced by
2. the amount of body fat.
3. age.
4. weight.
5. All of the answer choices are correct.
6. the amount of thyroxin produced by the thyroid.
7. A serving of 30 grams of almonds may have 190 calories listed on a nutrition label. This represents enough energy to raise the temperature of
8. 30 kilograms of water 190°C.
9. 190 grams of water 1°C.
10. 30 grams of water 190°C.
11. 90 kilograms of water 1°C.
12. The amount of energy required to raise the temperature of 1 kilogram of water by 1° Celsius is a
13. joule.
14. None of the answer choices is correct.
15. kilocalorie.
16. calorie.
17. measure of density.

True / False Questions

1. A raw peanut with almost 2 calories of energy has 2,000 times the energy required to raise the temperature of 1 gram water by 1°C.

True False

Multiple Choice Questions

1. An example (or examples) of potential energy is/are
2. light and chemical bonds.
3. concentration gradients.
4. chemical bonds.
5. chemical bonds and concentration gradients.
6. light.
7. Which statement is not part of the first law of thermodynamics?
8. Any energy transformation loses some energy to its surroundings as heat.
9. The amount of energy in the universe is constant.
10. Energy cannot be created or destroyed.
11. Energy can be converted to other forms of energy.
12. None of the answer choices is correct.
13. Kinetic energy can be described as energy in motion. Which of the following is not an example of kinetic energy?
14. random molecular movement
15. light
16. heat
17. the energy in chemical bonds
18. sound
19. Entropy is a measure of
20. order.
21. kinetic energy.
22. potential energy.
23. disorder.
24. complexity.

True / False Questions

1. You are cold. Your body begins a shivering response. You quickly rub your hands together, and the friction produces a small amount of heat. The heat is evidence of increasing entropy.

True False

Multiple Choice Questions

1. An endergonic reaction is a reaction that is characterized by
2. having products with lower energy than the reactants.
3. yielding smaller product molecules than the original reactants.
4. often having higher energy in product molecules than the reactants, and yielding larger product molecules.
5. having products with higher energy than the reactants.
6. yielding larger product molecules than the original reactants.
7. The breakdown of glucose to carbon dioxide and water is an
8. exergonic reaction in photosynthesis.
9. endergonic or exergonic reaction, depending on the step.
10. endergonic reaction in photosynthesis.
11. exergonic reaction in cellular respiration.
12. endergonic reaction in cellular respiration.
13. At chemical equilibrium
14. no reactions are occurring in either direction.
15. there are no more products being formed.
16. there are no more reactants for the cell to utilize.
17. the amount of reactants is equal to the amount of products.
18. reaction rates are in balance.

Oxidation and reduction reactions are typically linked within a cell. They are part of most matter and energy transformations necessary for vital life functions.

1. Oxidation-reduction reactions
2. are not used by living cells.
3. transfer protons from one molecule to another.
4. reduce the amount of oxygen in the cell.
5. transfer electrons from one molecule to another.
6. increase the amount of oxygen in the cell.
7. Oxidation means
8. the gain of oxygen by a cell.
9. the loss of electrons from a molecule.
10. the gain of electrons by a molecule.
11. the loss of oxygen and an electron.
12. the loss of oxygen by a cell.
13. Reduction means
14. the gain of electrons by a molecule.
15. the loss of oxygen from a cell.
16. the gain of oxygen by a cell.
17. the gain of oxygen and an electron.
18. the loss of electrons by a molecule.
19. Oxidation-reduction reactions
20. remove electrons from both molecules involved.
21. remove protons from one molecule and join them to another molecule.
22. never occur at the same time.
23. remove electrons from one molecule and add them to another molecule simultaneously.
24. remove oxygen from the cell.

True / False Questions

1. Each protein in an electron transport chain is sequentially oxidized, then reduced, allowing small amounts of energy to be released

for use by the cell during each transfer.

True False

Multiple Choice Questions

1. Coupled reactions are reactions in which an
2. exergonic reaction drives a spontaneous reaction.
3. exergonic or endergonic reaction provides products not used for other reactions.
4. exergonic reaction drives an endergonic reaction.
5. endergonic reaction drives a spontaneous reaction.
6. endergonic reaction drives an exergonic reaction.
7. The process of phosphorylation
8. All of the answer choices are correct.
9. may change the shape of the target molecule.
10. adds a phosphate group to a molecule.
11. removes a phosphate group from a molecule.
12. may energize the target molecule.
13. An enzyme is
14. always a protein.
15. not necessary to sustain life in a cell.
16. All of the answer choices are correct.
17. an organic molecule that catalyzes a cellular reaction.
18. used up in a reaction.
19. A cell produces proteins when ribosomes (a form of RNA and protein) and transfer RNA (tRNA) work together. Specific amino acids are brought by tRNA into the ribosome, where they are rapidly connected by covalent bonds. This indicates that ribosomes are

acting as

1. enzymes.
2. substrates.
3. a source of energy.
4. active sites.
5. reactants.
6. Enzymes speed chemical reactions by
7. supplying energy to the reaction process.
8. lowering the energy required to start a chemical reaction.
9. lowering the amount of reactants that are needed.
10. maintaining chemical equilibrium.
11. raising the temperature of the surroundings.

This diagram shows the basic structure and function of an enzyme, acting to catalyze a cell's chemical reaction.

1. The region of an enzyme that catalyzes reactions is called a(n)
2. cofactor site.
3. binding pocket.
4. reaction site.
5. catalyst site.
6. active site.
7. The molecule that fits into the active site of an enzyme and reacts with the enzyme is
8. always a carbohydrate.
9. an analog.
10. always a protein.
11. always broken down by the enzyme.
12. a substrate.
13. Competitive inhibition of enzymes occurs
14. when a substance other than the substrate binds at the active site of an enzyme.
15. when the product, or other substances, instead of the reactant, bind to the active site of the enzyme.
16. when a substance binds to an enzyme at a site away from the active site.
17. by blocking the production of an enzyme.
18. when the product, instead of the reactant, of a reaction binds to the active site.
19. Noncompetitive inhibition of enzymes occurs
20. when a cofactor, instead of a reactant, binds to the enzyme active site.
21. when the product, instead of the reactant, of a reaction binds to the active site.
22. by blocking the production of an enzyme.
23. when a substance binds to an enzyme at a site away from the active site.
24. when a substance other than the substrate binds at the active site of an enzyme.

True / False Questions

1. Cofactors, required to stabilize enzymes, are often in our diets as vitamins, minerals, and metals.

True False

Multiple Choice Questions

1. Determine which of these statements best summarizes the cellular regulation of concentration gradients.
2. Selective permeability of the cell membranes results in equal amounts of substances inside and outside the cell.
3. Enzymes are used in the cell to build molecules on one side of membranes to establish concentration gradients.
4. Membrane phospholipids and proteins regulate transport functions to establish concentration gradients or equilibria.
5. Passive and active transport both function with transport proteins to move materials across the cell membranes.
6. The cellular regulations require large amounts of energy to maintain equilibrium of materials.
7. Simple diffusion
8. moves molecules against a concentration gradient.
9. cannot occur without a membrane present.
10. requires energy.
11. utilizes proteins to move molecules across a membrane.
12. does not require energy.
13. The diffusion of water across a selectively permeable (biological) membrane is
14. a rare occurrence.
15. active transport.
16. a process that always requires proteins.
17. always beneficial to a cell.
18. osmosis.
19. If a cell has a greater concentration of solute than its environment, the cell
20. is isotonic to the environment.
21. will not experience a net gain or loss of water.
22. will die.
23. is hypertonic to the environment.
24. is hypotonic to the environment.
25. If the environment surrounding a cell has a lower concentration of solute than the cell, the
26. environment is hypotonic to the cell.
27. environment is isotonic to the cell.
28. cell will die.
29. cell will not experience a net gain or loss of water.
30. environment is hypertonic to the cell.
31. If a cell has a 95% concentration of water in its cytoplasm and the environment surrounding the cell has a 90% concentration of water, water will flow
32. into the cell by osmosis.
33. out of the cell by active transport.
34. out of the cell by osmosis.
35. into the cell by active transport.
36. into the cell by facilitated diffusion.
37. Turgor pressure in plant cells is
38. due in part to osmosis.
39. a result of the walled cell being in a hypotonic environment.
40. All of the answer choices are correct.
41. the force of water against the inside of the cell wall.
42. necessary to keep plants from wilting.
43. Much medical advice towards heart health indicates that you should eat less sodium (table salt). Notable higher risks of high sodium may include high blood pressure and damage to arteries or organs in your body. If you eat a single meal with large amounts of salt to

suit your taste, which of these may result within minutes, as the sodium enters your bloodstream?

1. Your blood will become hypotonic, and water in your body tissues will flow into your arteries, inflating them.
2. Your blood will become hypertonic, and water in your body tissues will flow into your arteries, inflating them.
3. Simple diffusion of water and sodium will both balance in an isotonic condition between arteries and body tissues.
4. You should expect no change in the concentration gradient because of a single meal, rather than lifestyle and diet.
5. Your blood will become hypotonic, and water in your arteries will flow into your tissues, inflating them.
6. Active transport is different from simple diffusion in that active transport
7. requires energy.
8. All of the answer choices are correct.
9. moves molecules against a concentration gradient.
10. requires transport proteins embedded within the cell membrane.
11. moves molecules from an area of lower concentration to an area of higher concentration.
12. Phagocytosis of an infective bacterium by a white blood cell is a subset type of
13. exocytosis.
14. facilitated diffusion.
15. simple diffusion.
16. active transport.
17. endocytosis.

When a cell "burns" food, electrons are released from chemical bonds in the food, and passed through an electron transport chain generating a proton gradient. As the protons pass through an ATPase the energy is used to generate ATP.

1. Which of the following are examples of potential energy associated with our food consumption and metabolism?
2. electrons moving through the electron transport chain, and protons moving through ATPase
3. electrons in chemical bonds of food molecules, proton gradients, and ATP molecules
4. electrons from food molecules moving through the electron transport chain, and a proton gradient
5. protons moving through ATPase by facilitated diffusion, ATP molecules
6. All of the answer choices are correct.
7. Which of the following are examples of kinetic energy?
8. electrons in chemical bonds of the food molecules, proton gradients established, ATP molecules
9. All of the answer choices are correct.
10. electrons from food molecules moving through the electron transport chain, and protons moving through ATPase
11. protons moving through ATPase by facilitated diffusion, ATP molecules
12. electrons from food molecules moving through electron transport chain, proton gradients established
13. When electrons are removed from a food molecule, it is
14. being oxidized.
15. an endergonic reaction.
16. an exergonic reaction.
17. being reduced.
18. in equilibrium.
19. Firewood is made up of cellulose, which is a polymer of glucose molecules. When burning, heat and light are given off, indicating that a(n) reaction is occurring.
20. potential energy
21. endergonic
22. equilibrium
23. kinetic energy
24. exergonic
25. If you drop a rubber ball, it doesn't bounce back to the height you dropped it from. This is consistent with
26. the second law of thermodynamics.
27. the first law of thermodynamics.
28. conversion of kinetic energy into potential energy.
29. conversion of kinetic energy into entropy.
30. conversion of entropy into potential energy.

This diagram summarizes energy transfers and molecule exchanges among plants and animals, as you will later learn we call producers and consumers.

1. Plants require energy to perform photosynthesis. Photosynthesis uses the energy, water, and carbon dioxide to make glucose, which is stored for energy. Because energy is initially required, photosynthesis is a(n) reaction.
2. kinetic energy
3. potential energy
4. exergonic
5. equilibrium
6. endergonic
7. The energy source that powers the process of photosynthesis is
8. water.
9. oxygen.
10. sunlight.
11. carbon dioxide.
12. glucose.
13. The molecular reactants for photosynthesis are
14. glucose and sunlight.
15. organic compounds.
16. water and carbon dioxide.
17. glucose and water.
18. glucose and carbon dioxide.
19. For animals and other organisms consuming food, the molecular reactants to cellular respiration is/are
20. glucose and oxygen.
21. entropy.
22. carbon dioxide and water.
23. glucose and carbon dioxide.
24. digestive enzymes.
25. The CFTR is a normal membrane protein used to move chloride ions out of a cell by active transport. This is an example of
26. a reduction reaction.
27. a reaction coupled with the hydrolysis of ATP.
28. an oxidation reaction.
29. equilibrium.
30. a reaction coupled with the production of ATP.
31. Once ATP donates its phosphate to a coupled reaction it becomes ADP. The ADP
32. can be recharged in an exergonic reaction to form ATP.
33. becomes the needed potential energy source for another coupled reaction.
34. is a waste product that must be broken down.
35. can be recharged in an oxidation reaction to form ATP.
36. can be recharged in an endergonic reaction to form ATP.
37. A bowl of sugar water is very stable. In a cell, however, it is rapidly broken down into carbon dioxide and water, releasing stored energy. What is the best explanation for this observation?
38. Enzymes in the cell catalyze the breakdown of the glucose.
39. Cells use energy to break down the glucose.
40. Glucose is only broken down while dissolving into a watery solution, such as inside the cell.
41. Glucose cannot be broken down outside of a cell.
42. Glucose becomes more chemically reactive inside of a cell.
43. Phenylalanine hydrolase is an enzyme produced by the liver to break down the amino acid phenylalanine. Why would phenylalanine accumulate in patients with phenylketonuria?
44. They lack an inhibitor of the enzyme to break down phenylalanine.
45. They produce too much phenylalanine.
46. They lack the enzyme to break down phenylalanine.
47. They lack the enzyme to produce phenylalanine.
48. Your liver produces 90% of the cholesterol found in your body. When cholesterol levels get too high, the first enzyme in the pathway of cholesterol synthesis is inhibited. This is an example of
49. positive feedback.
50. negative feedback.
51. equilibrium.
52. denaturation.
53. a coenzyme.
54. One way to produce a vaccine is to heat a virus or bacteria and then inject the inactive pathogen as a vaccination. How would the heat inactivate a virus?
55. by inhibiting its metabolism
56. by destroying the membrane
57. by blocking facilitated diffusion
58. by denaturing proteins
59. All of the answer choices are correct.
60. Simple diffusion occurs naturally as it of a system.
61. decreases the kinetic energy
62. increases the entropy
63. increases the potential energy
64. decreases the equilibrium
65. All of the answer choices are correct.

Estuaries are locations where rivers flow into oceans, with tidal shifts changing the salt concentrations. Plants and animals that live in estuaries face a dilemma in maintaining water balance inside their cells. During high tide they are in salt water, while at low tide they are in fresh water.

1. At high tide a coastal plant or animal cell will be in
2. osmosis.
3. an isotonic solution.
4. a hypotonic solution.
5. a hypertonic solution.
6. equilibrium.
7. During high tide a plant or animal would be at risk of
8. dehydration by facilitated diffusion of salts.
9. dehydration due to active transport of salts.
10. cells bursting due to active transport of salts.
11. cells bursting by osmosis of water.
12. dehydration by osmosis of water.
13. During low tide a plant cell will have an advantage over an animal cell because of its
14. chloroplasts.
15. nucleus.
16. mitochondria.
17. plasma membrane.
18. cell wall.

Up to 25% of a cell's ATP is used to run sodium-potassium pumps. Without the resulting sodium and potassium gradients, neurons and muscles cannot fire properly.

1. The sodium-potassium pump catalyzes
2. equilibrium.
3. facilitated diffusion.
4. osmosis.
5. active transport.
6. diffusion.
7. If a person is poisoned with cyanide, they cannot generate ATP, and die within a few minutes. In relation to the sodium-potassium pump, what specific impact would cyanide have on concentrations across the cell membrane?
8. Sodium concentration would be higher outside the cell, while potassium concentration would be higher inside the cell.
9. Both sodium and potassium concentrations would become isotonic outside the cell.
10. Sodium and potassium concentrations would both be higher inside the cell.
11. Both sodium and potassium concentrations would reach equilibrium conditions across the cell membrane.
12. Sodium and potassium concentrations would both be higher outside the cell.
13. Movement of molecules down a concentration gradient is an example of
14. active transport.
15. kinetic energy.
16. potential energy.
17. oxidation.
18. reduction.
19. Cholera is a bacterial disease, in which fatal dehydration can occur due to loss of water into the intestines. Cystic fibrosis is a human genetic disease characterized by excess mucus buildup on the linings of the lungs, making breathing difficult. Cholera acts on intestine cells to force water transport out of the cells and the body. Cystic fibrosis has an abnormal CFTR transport protein that limits water transport out of the cells and the body. How does the bacteria that causes cholera, Vibrio cholera, trigger potentially

life-threatening diarrhea?

1. Cholera toxin stimulates CFTR, leading to decreased transport of water into the intestines.
2. Cholera toxin causes a DNA genetic mutation that modifies the function of CFTR proteins.
3. Cholera toxin inhibits CFTR, leading to decreased transport of water into the intestines.
4. Cholera toxin inhibits CFTR, leading to increased transport of water into the intestines.
5. Cholera toxin stimulates CFTR, leading to increased transport of water into the intestines.

True / False Questions

1. Whenever ATP is produced by a chemical reaction, some energy is lost into the surroundings as heat.

True False

1. The first and second laws of thermodynamics apply to nonliving systems like gasoline engines but do not apply to reactions in living cells.

True False

1. Exergonic reactions do not require activation energy to get started.

True False

1. Reduction is the gain of electrons by an atom or molecule.

True False

1. An enzyme is a lipid that catalyzes chemical reactions.

True False

1. When an end product of a reaction pathway is in excess and inhibits the first enzyme of the pathway, this is an example of positive feedback.

True False

1. A reason that some antibiotics harm bacteria but not humans is because these antibiotics inhibit enzymes only found in bacteria.

True False

1. Phagocytosis is a process that cells use to move large particles in through the cell membrane.

True False

Multiple Choice Questions

1. Of these membrane transport processes, which do/does not make use of a vesicle?
2. phagocytosis
3. osmosis
4. pinocytosis
5. neither osmosis nor facilitated diffusion
6. facilitated diffusion
7. Which of these membrane transport processes does not require membrane proteins?
8. osmosis
9. facilitated diffusion
10. active transport pumps
11. endocytosis
12. All of the answer choices are correct.

True / False Questions

1. Receptor-mediated endocytosis is a specialized, more selective method of cell membrane transport than pinocytosis.

True False