8.
2 Cell respiration
Oxidation and reduction
1. *18N.1.HL.TZ0.31
Which is a reduction reaction?
A. ATP changing to ADP
B. Maltose changing to glucose
C. FAD changing to FADH2
D. NADPH changing to NADP
Answer: C
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The chemistry of respiration
2. *16M.1.HL.TZ0.10
The diagram represents the Krebs cycle.
What processes are occurring at I and II?
Answer: D
3. *16N.1.HL.TZ0.30
Which process requires oxygen in aerobic cell respiration?
A. Oxidation of triose phosphate
B. Reduction of hydrogen carriers
C. Maintaining an oxygen concentration gradient in mitochondria
D. Accepting electrons at the end of the electron transport chain
Answer: D
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4. 17M.1.HL.TZ1.29
The diagram shows a mitochondrion. Which letter indicates the structure where ATP synthase is
located?
Answer: C
5. *17M.1.HL.TZ2.14
This reaction occurs in mitochondria.
What explains that this reaction enables energy to be converted into a usable form?
A. The oxidized NAD+ will transfer the energy from the C6 compound to ATP.
B. The chemical energy stored in the C 6 compound is used to reduce NAD + allowing ATP
production.
C. Energy stored in the CO2 molecule will generate an electron gradient.
D. The C6 compound is reduced and the energy resulting from the removal of one carbon is used
to oxidize NAD+.
Answer: B
6. *17N.1.HL.TZ0.29
Which reaction does not cause a net release of energy?
A. ADP combines with inorganic phosphate to form ATP
B. ATP releases inorganic phosphate to form ADP
C. Loss of hydrogen from reduced NAD
D. Oxidation of reduced FAD
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Answer: A
7. 17N.1.HL.TZ0.31
The image shows a portion of a cell containing a mitochondrion.
Where do glycolysis and electron transport occur?
Answer: D
8. *18M.1.HL.TZ1.30
What happens when pyruvate is converted to acetyl CoA in the link reaction?
A. Decarboxylation
B. Phosphorylation
C. Hydrolysis
D. Reduction of pyruvate
Answer: A
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9. *18M.1.HL.TZ2.14
The following processes occur in aerobic cell respiration.
I. Decarboxylation of pyruvate
II. Diffusion of protons through ATP synthase
III. Phosphorylation of glucose
Which is the correct sequence for these processes?
Answer: D
10. *18N.1.HL.TZ0.29
What term is used for ATP synthesis coupled to electron transport and proton movement?
A. Chemiosmosis
B. Oxidation
C. Glycolysis
D. Cell respiration
Answer: A
11. *19M.1.HL.TZ1.30
The electron micrograph shows a section through part of an animal cell.
Which process is occurring on the structures labelled X?
A. The Krebs cycle
B. The link reaction
C. Glycolysis
D. Phosphorylation of ADP
Answer: D
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12. *19M.1.HL.TZ2.15
The diagram shows compounds in the Krebs cycle labelled as X, Y and Z.
How many carbon atoms are there in Y and
in the acetyl group of acetyl CoA?
Answer: A
13. *19N.1.HL.TZ0.30
The diagram shows the link reaction between glycolysis and the Krebs cycle.
Which type of reaction is occurring?
A. Pyruvate is carboxylated.
B. CO2 is oxidized.
C. NAD+ is reduced.
D. Pyruvate is phosphorylated.
Answer: C
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14. *20N.1.HL.TZ0.31
Two reactions of the Krebs cycle are shown.
What type of reactions are isocitrate and oxalosuccinate undergoing?
Answer: D
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