Question 1

Which statement best supports the hypothesis that glycolysis is an ancient metabolic pathway that originated before the last universal common ancestor of life on Earth?

Accepted Answer

A)   Glycolysis is widespread and is found in the domains Bacteria, Archaea, and Eukarya.
B)   Glycolysis neither uses nor needs O2.
C)   Glycolysis is found in all eukaryotic cells.
D)   The enzymes of glycolysis are found in the cytosol rather than in a membrane-enclosed organelle.
E)   Ancient prokaryotic cells, the most primitive of cells, made extensive use of glycolysis long before oxygen was present in Earth's atmosphere.

Question 2

Where do the catabolic products of fatty acid breakdown enter into the citric acid cycle?

Accepted Answer

A)   pyruvate
B)   malate or fumarate
C)   acetyl CoA
D)   α-ketoglutarate
E)   succinyl CoA

Question 3

The ATP made during glycolysis is generated by

Accepted Answer

A)   substrate-level phosphorylation.
B)   electron transport.
C)   photophosphorylation.
D)   chemiosmosis.
E)   oxidation of NADH to NAD+.

Question 4

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?

Accepted Answer

A)   the citric acid cycle
B)   the electron transport chain
C)   glycolysis
D)   synthesis of acetyl CoA from pyruvate
E)   reduction of pyruvate to lactate

Question 5

Most CO2 from catabolism is released during

Accepted Answer

A)   glycolysis.
B)   the citric acid cycle.
C)   lactate fermentation.
D)   electron transport.
E)   oxidative phosphorylation.

Question 6

Why are carbohydrates and fats considered high-energy foods?

Accepted Answer

A)   They have a lot of oxygen atoms.
B)   They have no nitrogen in their makeup.
C)   They can have very long carbon skeletons.
D)   They have a lot of electrons associated with hydrogen.
E)   They are easily reduced.

Question 7

The direct energy source that drives ATP synthesis during respiratory oxidative phosphorylation in eukaryotic cells is

Accepted Answer

A)   oxidation of glucose to CO2 and water.
B)   the thermodynamically favorable flow of electrons from NADH to the mitochondrial electron transport carriers.
C)   the final transfer of electrons to oxygen.
D)   the proton-motive force across the inner mitochondrial membrane.
E)   the thermodynamically favorable transfer of phosphate from glycolysis and the citric acid cycle intermediate molecules of ADP.

Question 8

Which of the following statements describes NAD+?

Accepted Answer

A)   NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle.
B)   NAD+ has more chemical energy than NADH.
C)   NAD+ is oxidized by the action of hydrogenases.
D)   NAD+ can donate electrons for use in oxidative phosphorylation.
E)   In the absence of NAD+, glycolysis can still function.

Question 9

Starting with citrate, which of the following combinations of products would result from three acetyl CoA molecules entering the citric acid cycle (see Figure 7.1) ?

Accepted Answer

A)   1 ATP, 2 CO2, 3 NADH, and 1 FADH2
B)   2 ATP, 2 CO2, 3 NADH, and 3 FADH2
C)   3 ATP, 3 CO2, 3 NADH, and 3 FADH2
D)   3 ATP, 6 CO2, 9 NADH, and 3 FADH2
E)   38 ATP, 6 CO2, 3 NADH, and 12 FADH2

Question 10

When an individual is exercising heavily and when the muscle becomes oxygen-deprived, muscle cells convert pyruvate to lactate. What happens to the lactate in skeletal muscle cells?

Accepted Answer

A)   It is converted to NAD+.
B)   It produces CO2 and water.
C)   It is taken to the liver and converted back to pyruvate.
D)   It reduces FADH2 to FAD+.
E)   It is converted to alcohol.

Exam 7: Cellular Respiration and Fermentation

Which of the following statements describes NAD+?

Correct Answer
verified

The ATP made during glycolysis is generated by

Correct Answer
verified

The direct energy source that drives ATP synthesis during respiratory oxidative phosphorylation in eukaryotic cells is

Correct Answer
verified

When an individual is exercising heavily and when the muscle becomes oxygen-deprived, muscle cells convert pyruvate to lactate. What happens to the lactate in skeletal muscle cells?

Correct Answer
verified

Why are carbohydrates and fats considered high-energy foods?

Correct Answer
verified

Most CO2 from catabolism is released during

Correct Answer
verified

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?

Correct Answer
verified

Starting with citrate, which of the following combinations of products would result from three acetyl CoA molecules entering the citric acid cycle (see Figure 7.1) ?

Correct Answer
verified

Which statement best supports the hypothesis that glycolysis is an ancient metabolic pathway that originated before the last universal common ancestor of life on Earth?

Correct Answer
verified

Where do the catabolic products of fatty acid breakdown enter into the citric acid cycle?

Correct Answer
verified

Exam 7: Cellular Respiration and Fermentation

Which of the following statements describes NAD+?

Correct AnswerverifiedShow Answer

The ATP made during glycolysis is generated by

Correct AnswerverifiedShow Answer

The direct energy source that drives ATP synthesis during respiratory oxidative phosphorylation in eukaryotic cells is

Correct AnswerverifiedShow Answer

When an individual is exercising heavily and when the muscle becomes oxygen-deprived, muscle cells convert pyruvate to lactate. What happens to the lactate in skeletal muscle cells?

Correct AnswerverifiedShow Answer

Why are carbohydrates and fats considered high-energy foods?

Correct AnswerverifiedShow Answer

Most CO2 from catabolism is released during

Correct AnswerverifiedShow Answer

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?

Correct AnswerverifiedShow Answer

Starting with citrate, which of the following combinations of products would result from three acetyl CoA molecules entering the citric acid cycle (see Figure 7.1) ?

Correct AnswerverifiedShow Answer

Which statement best supports the hypothesis that glycolysis is an ancient metabolic pathway that originated before the last universal common ancestor of life on Earth?

Correct AnswerverifiedShow Answer

Where do the catabolic products of fatty acid breakdown enter into the citric acid cycle?

Correct AnswerverifiedShow Answer

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