Honors Biology Ch. 9 Cellular Respiration
63. Without oxygen, a cell can extract a net gain of only _________ molecules of ATP from each glucose molecule.
2
How many ATP molecules are formed by fermentation?
2
Two turns of the Krebs cycle will result in ____ ATP molecules.
2
80. Describe glycolysis in terms of energy input, energy output, and net gain of ATP. Glycolysis requires an initial input of __ ATPs and produces ___ ATPs, for a net gain of ___ ATPs.
2 4 2
List the main events of glycolysis. How many ATP molecules are produced and consumed by glycolysis? What effect does the presence of oxygen have on the events that follow glycolysis? Glycolysis is the breakdown of glucose into two molecules of pyruvic acid, producing 4 ATP molecules. An initial input of ___ ATP molecules is required to start glycolysis; thus, there is a net gain of 2 ATP molecules. This process produces two high-energy electrons, which are passed to NAO+ to form NADH. If oxygen is present, glycolysis leads to the Krebs cycle and the electron transport chain. lf oxygen is not present, glycolysis is followed by the rest of ____.
2 fermentation
What are the energy totals produced by one molecule of pyruvic acid entering the Krebs cycle? One molecule of pyruvic acid entering the Krebs cycle results in __ NADH, ___ FADH2, and __ ATP molecules.
4 1 1
69. If two pairs of electrons move down the electron transport chain, they will provide enough energy to produce about ________ ATP molecules.
6
What is the equation for cellular respiration?
602 + C6H12O6->6CO2 + 6H2O + Energy
86. What is the main function of the electron transport chain? The electron transport chain uses high-energy electrons from the Krebs cycle to convert ___ into ___.
ADP ATP
Identify the electron carriers of cellular respiration. Discuss the relationship between the electron carriers and the electron transport chain. The electron carriers of cellular respiration are NAD• and FAD. These molecules accept high-energy electrons and move to the electron transport chain. The electron transport chain produces ___ molecules. Without the electron carriers and the electron transport chain, cells would not have enough energy to function and would ___.
ATP die
Which pathways does the body use to release energy during exercise? Discuss these pathways in terms of a footrace. The first few seconds of a race are powered by the __ that the muscle cells already have on hand. Then, the muscle cells begin producing ATP by ___ ____ fermentation-this would be around the 50-meter mark of the race. After about 90 seconds, however, cellular respiration is the only way to generate a continuing supply of ATP.
ATP lactic acid
T. or F? The first few seconds of intense exercise use up the cell's stores of fat.
F, ATP
T or F? In prokaryotes, the electron transport chain is located in the inner membrane of the mitochondria.
F, cell membrane
T or F? Cellular respiration releases energy by breaking down glucose in the presence of carbon dioxide?
F, oxygen
T. or F? Either cellular respiration or fermentation can be used to release energy, depending on the presence of carbohydrates?
F, oxygen
T or F? The reactants of photosynthesis are the same as the reactants of cellular respiration.
F, products
T or F? During the course of a long race, a person's muscle cells will use both cellular respiration and lactic acid fermentation to produce ATP.
T
T or F? If an animal cell stops carrying out cellular respiration, it will die.
T
T or F? If you swim aerobically for 30 minutes, your body has probably started to break down stored molecules. such as fats. for energy.
T
T or F? NADH and FADH2 carry electrons from the Krebs cycle to tbe electron transport chain.
T
T or F? The Krebs cycle releases energy in the form of ATP.
T
T or F? The products of glycolysis are 2 ATP, 2 NADH, and 2 pyruvic acid molecules.
T
T or F? Without the Krebs cycle, the electron transport chain would produce very few ATPs.
T
T or F? During photosynthesis, energy is stored in the form of fats.
T or F? F, carbohydrates
10. Glycolysis provides a cell with a net gain of a. 2 ATP molecules. b. 4 ATP molecules. c. 18 ATP molecules. d. 36 ATP molecules.
a
12. Glycolysis requires a. an energy input b. oxygen. c. hours to produce many ATP molecules. d. NADP•.
a
14. Which of the following acts as an electron carrier in cellular respiration? a. NAD• b. pyruvic acid c. ADP d. ATP
a
20. During lactic acid fermentation, a. NAO• is regenerated, allowing glycolysis to continue. b. glucose is split into three pyruvic acid molecules. c. oxygen is required. d. 3 ATP molecules are produced.
a
30. In eukaryotes, electron transport occurs in the a. mitochondria. b. chloroplasts. c. cell membrane. d. cytoplasm.
a
37. The energy needed to ivin a 2-miriutc footrace is produced mostly by a. lactic acid fermentation. b. ceUular respiration. c. using up stores of ATP. d. breaking down fats.
a
5. What is the correct equation for cellular respiration? a. 602 + C6H1106 ➔ 6C02 + 6H20 + Energy b. 6O2 + C6H1206 +Energy➔ 6C02 + 6H20 c. 6C02 + 6H20 ➔ 602 + C6H1206 + Energy d. 6CO, + 6H20 + Energy➔ 602 + C5H1206
a
6. Cellular respiration releases energy by breaking down a. food molecules. b. ATP. c. carbon dioxide. d. water.
a
9. Which of these processes takes place in the cytoplasm of a cell? a. glycolysis b. electron transport c. Krebs cycle d. all of the above
a
I. Which of the following is NOT a stage of cellular respiration? a. fermentation b. electron transport c. glycolysis d. Krebs cycle
a
Which of the following passes high-energy electrons into the electron transport chain? a. NADH and FADH2 b. ATP and ADP c. citric acid d. acetyl - CoA
a
What is this pathway called? Glucose to Pyruvic acid to Carbon dioxide + Ethyl alcohol + water
alcoholic fermentation
What are the two types of fermentation? How do their products differ? ______ fermentation produces carbon dioxide, alcohol, and NAD+, whereas ______ ______ fermentation produces lactic acid and NAD•.
alcoholic lactic acid
What roles does oxygen play in photosynthesis and in cellular respiration? Photosynthesis releases oxygen into the _____, whereas cellular respiration ____ oxygen to release energy from food.
atmosphere uses
39. All of the following are sources of energy during exercise EXCEPT a. stored ATP. b. alcoholic fermentation. c. lactic acid fermentation. d. cellular respiration.
b
41. How are cellular respiration and phowsynthesis almost opposite processes? a. Photosynthesis releases energy, and cellular respiration stores energy. b.Photosynthesis removes carbon dioxide from the atmosphere, and cellular respiration puts it back. c. Photosynthesis removes oxygen from the atmosphere. and cclJular respiration puts it back. d. all of the above
b
44. Plants cannot release energy from glucose using a. glycolysis. b. photosynthesis. c. the Krebs cycle. d. cellular respiration.
b
45. The products of photosynthesis are the a. products of cellular respiration. b. reactants of cellular respiration. c. products of glycolysis. d. reactants of fermentation.
b
8. Which of these is a product of cellular respiration? a. oxygen b. water c. glucose d. all of the above
b
Breathing heavily after running a race is your body's way of a. making more citric acid. b. repaying an oxygen debt. c. restarting glycolysis. d. recharging the electron transport chain.
b
Each pair of high-energy electrons that moves down the electron transport chain provides enough energy to a. transport water molecules across the membrane. b. convert 3 ADP molecules into 3 ATP molecules. c. convert carbon dioxide into water molecules. d. break glucose into pyruvic acid.
b
The Krebs cycle does not occur if a. oxygen is present. b. fermentation occurs. c. glycolysis occurs. d. carbon diox.ide is present.
b
Which process does NOT release energy from glucose? a. glycolysis b. photosynthesis c. fennentation d. cellular respiration
b
15. Lactic acid ferme.ntation occurs in a. bread dough. b. any environment containing oxygen. c. muscle cells. d. mitochondria.
c
16. The two main types of fermentation are called a. alcoholic and aerobic. b. aerobic and anaerobic. c. alcoholic and lactic acid. d. lactic acid and anaerobic.
c
17. One cause of muscle soreness is a. alcoholic fermentation. b. glycolysis. c. lactic acid fermentation. d. the Krebs cycle.
c
2. Which of lbe following is the correct sequence of evenls in cellular respiration? a. glycolysis ➔ fenuentation ➔ Krebs cycle b. Krebs cycle➔ electron transport➔ glycolysis c. glycolysis ➔ Krebs cycle➔ electron transport d. Krebs cycle➔ glycolysis ➔ electron transport
c
24. Which organism is NOT likely to carry out cellular respiration? a. tree b. mushroom c. anaerobic bacterium d. tiger
c
25. The starting molecule for the Krebs cycle is a. glucose. b. NADH. c. pyruvic acid. d. coenzyme A.
c
3. Which of the following is released during cellular respiration? a. oxygen b. air c. energy d. lactic acid
c
35. When the body needs to exercise for longer than 90 seconds, it generates ATP by carrying out a. lactic acid fermentation. b. alcoholic fe.nnentation. c. cellular respiration. d. gl ycolysis.
c
4. Cellular respiration uses one molecule of glucose 10 produce a. 2 ATP molecules. b. 34 ATP molecules. c. 36 ATP molecules. d. 38 ATP molecules.
c
42. Photosynthesis is to chloroplasts as cellular respiration is 10 a. chloroplasts. b. cytoplasm. c. mitochondria. d. nuclei.
c
7. What are the reactants in the equation for cellular respiration? a. oxygen and lactic acid b. carbon dioxide and water c. glucose and oxygen d. water and glucose
c
Cellular respiration is called an aerobic process because it requires a. light b. exercise c. oxygen d. glucose
c
During one turn, the Krebs cycle produces a. oxygen. b. lactic acid. c. electron carriers. d. glucose.
c
Which process is used to produce beer and wine? a. lactic acid fermentation b. glycolysis c. alcoholic fermentation d. the Krebs cycle
c
Which statement mainly explains why even well-conditioned athletes have to pace themselves for events thatlast several hours? a. Lactic acid fennentation can cause muscle soreness. b. Heavy breathing is needed to get rid of lactic acid. c. Cellular respiration releases energy more slowly than fermentation does. d. all of the above
c
Photosynthesis occurs only in plants, algae, and some bacleria. In contrast, ____________ occurs in all eukaryotic cells.
cellular respiration
Describe the main steps and the results of one turn of the Krebs cycle. During the Krebs cycle, pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions. Coenzyme A forms acetyl-CoA, which later becomes _____ acid. Citric acid is then broken down, ____, is liberated, and electrons are transferred to energy carriers. The energy tally from one molecule of pyruvic acid is 4 NADH, I FADH2, and I ATP.
citric CO2
What would happen if all the energy in glucose were released in just one step instead of gradually as it is in cellular respiration? How is the gradual process of cellular respiration advantageous to the cell? If the energy in glucose were released in just one step, most of the energy would be lost as light and heat. The light and heat could harm or even destroy the cell. The gradual process of cellular respiration allows the cell to _____ the release of energy into packages of ____ that can be used efficiently for cell activities.
control ATP
11. The starting molecule for glycolysis is a. ADP. b. pyruvic acid. c. citric acid. d. glucose.
d
19. Milk is convened to yogun under ce1tain conditions when the microorganisms in the milk produce acid. Which of these processes would you expect to be key in the production of yogurt? a. the Krebs cycle b. photosyntJ1esis c. alcoholic fermentation d. lactic acid fermentation
d
21. Tbe conversion of pyrnvic acid into lactic acid requires a. alcohol. b. oxygen. c. ATP. d. NADH.
d
22. In the presence of oxygen, glycolysis is followed by a. lactic acid fermentation. b. alcoholic fermentation. c. photosynthesis. d. the Krebs cycle
d
28. The Krebs cycle starts with a. lactic acid and yields carbon dioitide. b. glucose and yields 32 A TPs. c. pyruvic acid•and yields lactic acid or alco.hol. d. pyruvic acid and yields carbon dioxide.
d
43. Unlike photosynthesis. cellular respiration occurs in a. animal cells only. b. plant cells only. c. all but plant cells. d. all eukaryoric cells.
d
If you want to control your weight, how long should you exercise aerobically each time you exercise? a. at lea.5t 90 seconds b. less than 15 minutes c. 15 to 20 mi.nutes d. more than 20 minutes
d
The electron transport chain can be found in a. prokaryotes. b. animals. c. plants. d. all of the above
d
The energy of the electrons passing along tlic electron transport chain is used to make a. lactic acid. b. citric acid. c. alcohol. d. ATP.
d
Which of the following is NOT a product of glycolysis? a. NADH b. pyruvic acid c. ATP d. glucose
d
70. The ____________ is a series of carrier proteins.
electron transport chain
76. What is cellular respiration? the process that releases ___ by breaking down food molecules in the presence of ___.
energy oxygen
88. What three sources of ATP does your body use during a long aerobic exercise session? The body uses ATP that is already present in the muscle cells, ATP made from lactic acid _______, and ATP made from cellular ______.
fermentation respiration
85. Why is the Krebs cycle also known as the citric acid cycle? Citric acid is the ___ compound formed in the process.
first
77. List the three main stages of cellular respiration in order. Where does each stage take place in the cell? The three stages are as follows: ______ (which occurs in the cytoplasm), the ____ cycle (which occurs in the mitochondria), and ______ ________ (which occurs in the 1ni1ochondria).
glycolysis krebs electron transport
62. The tllree main stages of cellular respiration are ________ the Krebs cycle, and __________ _
glycolysis, electron transport
79. What happens during glycolysis? During glycolysis one molecule of glucose is broken in ___, producing two molecules of ___ acid.
half pyruvic
78. Cellular respiration is able to extract about 38 percent of the potential energy from glucose. What happens to the rest of the energy? Give an example. The rest of the energy is released as ___, as indicated by the fact that you feel warmer after exercising and are able to maintain a constant temperature even in ___ weather.
heat cold
87. What role does oxygen play in the electron transport chain? Oxygen is the final electron acceptor in the electron transport chain. which means that it is needed to get rid of low-energy electrons and H• ___.
ion
Explain how high-energy electrons are used by the electron transport chain. The electron transport chain uses the high-energy electrons from the ___ ____ to convert ADP into ATP. High-energy electrons are passed from one carrier protein to the next. Every 2 high-energy electrons that move down the chain result in enough energy to convert _ ADP molecules to _ ATP molecules, on average.
krebs cycle 3 3
89. What is an oxygen debt? An oxygen debt is the amount of oxygen needed to get rid of _____ ______ that has built up in muscle cells due to lactic acid fermentation.
lactic acid
72. A high level of lactic acid in the blood is a sign that ____________ has occurred.
lactic acid fermentation
73. A person who regularly does aerobic exercise takes in ________ oxygen than a sedentary person.
more
Compare lactic acid fermentation with alcoholic fermentation. Where does each process occur? What are the products of each process? Lactic acid fermentation occurs in animal ____ cells and in some microorganisms. Lactic acid fermentation converts glucose into lactic acid. In yeast cells, alcoholic fermentation takes place. Unlike lactic acid fermentation, alcoholic fermentation produces alcohol and CO2. Both types of fermentation result in 2 ATP molecules.
muscle CO2
81. Give two examples of fermenation. those that occur in the ____ and in rising bread ____.
muscles dough
61. Cellular respiration occurs only in the presence of ________ _
oxygen
71. The body gets rid of lactic acid in a chemical pathway that requires _______ _
oxygen
People who suffer from a heart attack often have an increased ratio of lactic acid to pyruvic acid in their hearts. What does this observation say about the availability of oxygen in the heart muscle cells of someone who has had a heart attack? How could you use this information to screen people who might be at risk for a heart attack? Lactic acid is an indication that lactic acid fermentation is occurring in muscle cells. Lactic acid fermentation occurs only in the absence of _____; thus, the heart cells may not have been receiving enough oxygen, a factor that could contribute to the occurrence of a heart attack. The level of ____ acid could be measured in certain parts of the heart as an indication of risk of heart attack.
oxygen lactic
If all autotrophs on Earth suddenly stopped carrying out _________ _ cellular respiration would soon stop too.
photosynthesis
Compare photosynthesis with cellular respiration. Photosynthesis and cellular respiration are almost opposite processes. The reactants of photosynthesis are the ____ of cellular respiration. The products of photosynthesis are the reactants of cellular respiration. Whereas photosynthesis "deposits energy, cellular respiration "withdraws" energy. Photosynthesis removes carbon dioxide from and releases oxygen into the atmosphere. Cellular respiration uses oxygen and gives off ____ _____.
products carbon dioxide
Glycolysis convens glucose into two molecules of __________ _
pyruvic acid
What happens to muscle cells during intense physical activity? During intense or prolonged physical activity, muscle cells may use oxygen faster than it can be supplied by the body. When the oxygen supply gets very low, the electron transport chain cannot function because oxygen serves as its final electron acceptor. As a result, NADH and FADH1 accumulate in the mitochondria and are not able to be recycled. This forces the Krebs cycle to ___. In this situation, the muscle cells continue to produce ATP by means of ___ _____ fermentation. This will cause muscle pain and fatigue.
stop lactic acid
