Most CO2 from catabolism is released during

Most CO2 from catabolism is released during

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








Answer: B

Which of the following is a true distinction between fermentation and cellular respiration?

Which of the following is a true distinction between fermentation and cellular respiration?

A. Only respiration oxidized Glucose
B. NADH is oxidized by the electron transport chain in respiration only
C. Fermentation, but not respiration, is an example of a catabolic pathway
D. Substrate-level phosphorylation is unique to fermentation
E. NAD+ functions as an oxidizing agent only in respiration








Answer: B

Cells do not catalyze carbon dioxide because

Cells do not catalyze carbon dioxide because 

A. It's double bonds are too stable to be broken
B. CO2 has fewer binding electrons than other organic compounds
C. CO2 is already completely reduced
D. CO2 is already completely oxidized
E. The molecule has too few atoms







Answer: D

When electrons flow along the electron transport chains of mitochondria, which of the following changes occur?

When electrons flow along the electron transport chains of mitochondria, which of the following changes occur?

A. The pH of the matrix increases
B. ATP synthase pumps protons by active transport
C. The electrons gain free energy
D. The cytochromes phosphorylated ADP to form ATP
E. NAD+ is oxidized





Answer: A

The final electron acceptor of the electron transport chain that functions in aerobic oxidative phosphorylation is

The final electron acceptor of the electron transport chain that functions in aerobic oxidative phosphorylation is

A. Oxygen
B. Water
C. NAD+
D. Pyruvate
E. ADP








Answer: A

In mitochondria, exergonic redox reactions

In mitochondria, exergonic redox reactions

A. Are the source of energy driving prokaryotic ATP synthesis
B. Are directly coupled to substrate-level phosphorylation
C. Provide the energy that establishes the proton gradient
D. Reduce carbon atoms to carbon dioxide
E. Are coupled via phosphorylated intermediates to endergonic processes






Answer: C

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

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

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





Answer: C

The immediate energy source that drives ATP Synthesis by ATP synthase during oxidative phosphorylation is

The immediate energy source that drives ATP Synthesis by ATP synthase during oxidative phosphorylation is

A. The oxidation of glucose and other organic compounds
B. The flow of electrons down the electron transport chain
C. The affinity of oxygen for electrons
D. The H+ concentration gradient across the inner mitochondrial membrane
E. The transfer of phosphate to ADP





Answer: D

Even though plants carry on photosynthesis, plant cells still use their mitochondria for oxidation of pyruvate. When and where will this occur?

Even though plants carry on photosynthesis, plant cells still use their mitochondria for oxidation of pyruvate. When and where will this occur?

A. In the photosynthesis cells in the light, while photosynthesis occurs concurrently
B. In non-photosynthesizing cells only
C. In cells that are storing glucose only
D. In photosynthesizing cells in dark periods and in other tissues all the time
E. In photosynthesizing cells in the light and in other tissues in the dark







Answer: D

What is the purpose of beta oxidation in respiration?

What is the purpose of beta oxidation in respiration?

A. Oxidation of glucose
B. Oxidation of pyruvate
C. Feedback regulation
D. Control of ATP accumulation
E. Breakdown of fatty acids






Answer: E

Phosphofructokinase is an allosterically enzyme that catalyzes the conversion of fructose-6-phosphate to fructose-1, 6-bisphosphate, an early step of glycolysis. In the presence of oxygen, an increase in the amount ATP in a cell would be expected to

Phosphofructokinase is an allosterically enzyme that catalyzes the conversion of fructose-6-phosphate to fructose-1, 6-bisphosphate, an early step of glycolysis. In the presence of oxygen, an increase in the amount ATP in a cell would be expected to 

A. Inhibit the enzyme and thus slow the rates of glycolysis and the citric acid cycle
B. Activate the enzyme and thus slow the rates of glycolysis and the citric acid cycle
C. Inhibit the enzyme and thus increase the rates of glycolysis and the citric acid cycle
D. Activate the enzyme and increase the rates of glycolysis and the citric acid cycle
E. Inhibit the enzyme and thus increase the rate of glycolysis and the concentration of citrate

Answer: A

Phosphofructokinase is an important control enzyme in the regulation of cellular respiration. Which of the following statements describes a function of phosphofructokinase?

Phosphofructokinase is an important control enzyme in the regulation of cellular respiration. Which of the following statements describes a function of phosphofructokinase?

A. It is activated by AMP
B. It is activated by ATP
C. It is inhibited by citrate, an intermediate of the citric acid cycle
D. It catalyzes the conversion of fructose-6-phosphate, an early step of glycolysis
E. It is an allosterically enzyme






Answer: E

You have a friend who lost 7kg of fat on a low carb diet. How did the fat leave her body?

You have a friend who lost 7kg of fat on a low carb diet. How did the fat leave her body?

A. It was released as CO2 and H2O
B. Chemical energy was converted to hear and then released
C. It was converted to ATP, which weighs much less than fat
D. It was broken down to amino acids and eliminated from the body
E. It we converted to urine and eliminated from the body

When muscle cells undergo anaerobic respiration, they become fatigued and painful. This is now known to be caused by

When muscle cells undergo anaerobic respiration, they become fatigued and painful. This is now known to be caused by

A. Buildup of pyruvate
B. Buildup of lactate
C. Increase in sodium ions
D. Increase in potassium ions
E. Increase in ethanol

When muscle cells are oxygen deprived, the heart still pumps. What must the heart cells be able to do?

When muscle cells are oxygen deprived, the heart still pumps. What must the heart cells be able to do?

A. Derive sufficient energy from fermentation
B. Continue aerobic metabolism when skeletal muscle cannot
C. Transform lactate to pyruvate again
D. Remove lactate from the blood
E. Remove oxygen from lactate





Answer: B

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

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

A. It is converted to NAD+
B. It produced 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





Answer: C

Why is glycolysis considered to be one of the first metabolic pathways to have evolved?

Why is glycolysis considered to be one of the first metabolic pathways to have evolved?

A. It produces much less ATP than does oxidative phosphorylation
B. It is found in the cytosol, does not involve oxygen, and is present in most organisms
C. It is found in prokaryotic cells but not in eukaryotic cells
D. It relies on chemiosmosis which is a metabolic mechanism present only in the first cells-prokaryotic cells
E. It's requires the presence of membrane-enclosed cell organelles found only in eukaryotic cells

Answer: B

Glycolysis is thought to be one of the most ancient of metabolic processes. Which statement supports this idea?

Glycolysis is thought to be one of the most ancient of metabolic processes. Which statement supports this idea?

A. Glycolysis is the most widespread metabolic pathway
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 earths atmosphere

Answer: A

An organism is discovered that consumes a considerable amount of sugar, yet it does not gain much weight when denied air. Curiously, the consumption of sugar increases as the air is removed from the organisms environment, but the organism seems to thrive even in the absence of air. When return a normal air, the organism does fine. Which of the following best describes an organism?

An organism is discovered that consumes a considerable amount of sugar, yet it does not gain much weight when denied air. Curiously, the consumption of sugar increases as the air is removed from the organisms environment, but the organism seems to thrive even in the absence of air. When return a normal air, the organism does fine. Which of the following best describes an organism?

A. It must use a molecule other than oxygen to accept electrons from the electron transport chain
B. It is a normal eukaryotic organism
C. The organism obviously lacks the citric acid cycle and electron transport chain
D. It is an anaerobic organism
E. It is a facultative anaerobic





Answer: E

One function of both alcohol fermentation and lactic acid fermentation is to

One function of both alcohol fermentation and lactic acid fermentation is to

A. Reduce NAD+ to NADH
B. reduce FAD+ to FADH2
C. Oxidize NADH to NAD+
D. Reduce FADH2 to FAD+
E. None of the above







Answer: C