AP Biology - UNIT 4 EXAMVersion E
1. Inside an active mitochondrion, most electrons follow which pathway?
A) glycolysis → NADH → oxidative phosphorylation → ATP → oxygen
B) citric acid cycle → FADH2 → electron transport chain → ATP
C) electron transport chain → citric acid cycle → ATP → oxygen
D) pyruvate → citric acid cycle → ATP → NADH → oxygen
E) citric acid cycle → NADH → electron transport chain → oxygen
2. One carbon dioxide molecule reacts in each "turn" of the Calvin cycle. How many turns of the cycle are required for the synthesis of one glucose molecule?
A) 1 C) 3
B) 2 D) 6E) 12
3. All of the events listed below occur in the light reactions of photosynthesis except
A) oxygen is produced.
B) NADP+ is reduced to NADPH.
C) carbon dioxide is incorporated into PGA.
D) ADP is phosphorylated to yield ATP.
4. Which of the following statements about glycolysis is false?
A) Glycolysis has steps involving oxidation-reduction reactions.
B) The end products of glycolysis are CO2 and H2O.
C) Glycolysis can operate in the complete absence of O2.
D) The enzymes of glycolysis are located in the cytosol of the cell.
5. In addition to ATP, what are the end products of glycolysis?
A) CO2 and H2O
B) CO2 and pyruvate
C) NADH and pyruvate
D) CO2 and NADH
6. In glycolysis, for each molecule of glucose oxidized to pyruvate
A) 2 molecules of ATP are used and 4 molecules of ATP are produced.
B) 2 molecules of ATP are used and 2 molecules of ATP are produced.
C) 4 molecules of ATP are used and 2 molecules of ATP are produced.
D) 2 molecules of ATP are used and 6 molecules of ATP are produced.
7. In the presence of oxygen, the three-carbon compound pyruvate can be catabolized in the citric acid cycle. First, however, the pyruvate 1) loses a carbon, which is given off as a molecule of CO2, 2) is oxidized to form a two-carbon compound called acetate, and 3) is bonded to coenzyme A. These three steps result in the formation of
A) acetyl CoA, O2, and ATP.
B) acetyl CoA, FADH2, and CO2.
C) acetyl CoA, FAD, H2, and CO2.
D) acetyl CoA, NADH, H+, and CO2.
8. From one molecule of glucose, how many NADH, FADH2, & ATP are generated from the citrate cycle?
A) 3 NADH, 1 FADH2, & 1 ATP
B) 3 NADH, 1 FADH2, & 2 ATP
C) 6 NADH, 2 FADH2, & 2 ATP
D) 6 NADH, 2 FADH2, & 4 ATP
9. In chemiosmotic phosphorylation, what is the most direct source of energy that is used to
convert ADP + Pi to ATP?
A) energy released as electrons flow through the electron transport system
B) energy released from substrate-level phosphorylation
C) energy released from ATP synthase pumping hydrogen ions against their concentration gradient
D) energy released from movement of protons through ATP synthase
E) No external source of energy is required because the reaction is exergonic.
10. From one molecule of glucose, how many ATP are generated from pyruvate conversion by means of substrate level and oxidative phosphorylation?
A) 2C) 6
B) 4 D) 12E) 24
11. The function of both alcohol fermentation and lactic acid fermentation is to
A) reduce NAD+ to NADH.
B) oxidize NADH to NAD+.
C) reduce FAD+ to FADH2.
D) oxidize FADH2 to FAD+.
12. Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?
A) CO2 and glucose
B) H2O and O2
C) ATP and NADPH
D) electrons and H+
13. A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are not being absorbed by this pigment?
A) red and yellow
B) blue and violet
C) green and yellow
D) blue, green, and red
14. In the thylakoid membranes, what is the main role of the majority of pigment molecules?
A) split water and release oxygen to the reaction-center chlorophyll
B) harvest photons and transfer light energy to the reaction-center chlorophyll
C) synthesize ATP from ADP and Pi
D) transfer electrons to ferredoxin and then NADPH
15. Where does glycolysis takes place?
A) mitochondrial matrix
B) mitochondrial outer membrane
C) mitochondrial inner membrane
D) cytosol
16. All of the following are directly associated with photosystem II except
A) extraction of hydrogen electrons from the splitting of water.
B) release of oxygen.
C) harvesting of light energy by chlorophyll.
D) NADP+ reductase.
17. All of the following are directly associated with photosystem I except
A) harvesting of light energy by chlorophyll.
B) receiving electrons from plastocyanin.
C) P700 reaction-center chlorophyll.
D) extraction of hydrogen electrons from the splitting of water.
18. What is the primary function of the Calvin cycle?
A) use ATP to release carbon dioxide
B) use NADPH to release carbon dioxide
C) synthesize simple sugars from carbon dioxide
D) transport RuBP out of the chloroplast
19. Why are C4 plants able to photosynthesize with no apparent photorespiration?
A) They do not participate in the Calvin cycle.
B) They use PEP carboxylase to initially fix CO2.
C) They are adapted to cold, wet climates.
D) They conserve water more efficiently.
20. Photorespiration lowers the efficiency of photosynthesis, preventing the formation of
A) carbon dioxide molecules.
B) glyceraldehyde-3-phosphate molecules
C) ATP molecules.
D) NADPH molecules.
21. Plants that fix CO2 into organic acids at night when the stomata are open and carry out the Calvin cycle during the day when the stomata are closed are called
A) C3 plants.
B) C4 plants.
C) CAM plants.
D) B and C only.
22. In what respect are the photosynthetic adaptations of C4 plants and CAM plants similar?
A)In both cases, an enzyme other than rubisco carries out the first step in carbon fixation.
B) Both types of plants make sugar without the Calvin cycle.
C) In both cases, only photosystem I is used.
D) Both types of plants make most of their sugar in the dark.
23. The reaction below represents what type of reaction?
C6H12O6 + 6O2 6CO2 + 6H2O + energy
A) Aerobic respirationC) Glycolysis
B) Anaerobic respirationD) FermentationE) Photosynthesis
24. Which of the following statements is (are) correct about an oxidation-reduction (or redox) reaction?
A) The molecule that is reduced gains electrons.
B) The molecule that is oxidized loses electrons.
C) The molecule that is reduced loses electrons.
D) The molecule that is oxidized gains electrons.
E) Both A and B are correct.
25. In a plant cell, where are the ATP synthase complexes located?
A) thylakoid membraneC) inner mitochondrial membrane
B) plasma membrane D) A and C E) A, B, and C
26. All of the following stages are considered aerobic processes except
A) the citric acid cycleC) glycolysis
B) formation of acetyl CoAD) electron transport chainE) oxidative phosphorylation
27. Eukaryotes carry out oxidative phosphorylation in the mitochondrion. The analogous structure used by prokaryotes to carry out oxidative phosphorylation is the
A) nuclear membraneC) plasma membrane
B) cell wallD) ribosomeE) endoplasmic reticulum
28. All of the following statements are correct regarding the light reactions of photosynthesis except
A) the antennae pigments capture sunlight
B) the reaction center in photosystem II is P680
C) the electrons are activated and passed along an electron transport chain
D) light energy is converted to chemical energy
E) carbon dioxide is used to make glucose
29. When electrons are passed along the electron transport chain during noncyclic transfer, in photosystem I, this results in the production of
A) NADPHC) cytochrome
B) ATPD) waterE) glucose
30. Which of the following processes requires sunlight, ADP, and water?
A) Phtosystem IC) Glycolysis
B) Photosystem IID) Calvin cycleE) Electron transport chain
Short Answer
21. Electron transfer from NADH does not generate the same number of ATP via oxidative phosphorylation as FADH2 due to where these molecules feed electrons into the electron transport chain (E.T.C.). 1) How many ATP are generated from one molecule of NADH and how many from FADH2? 2) Where does each molecule deposit electrons into the E.T.C.? 3) How does this difference in where NADH or FADH2 deposit electrons account for the difference in the number of ATP generated per molecule?
(6 points)
22. How are C4 and CAM plants similar and different with regard to how they avoid photorespiration? (4 points)