Chapter 9: Cellular Respiration

In the overall process of glycolysis and cellular respiration, _____ is oxidized and _____ is reduced. (eText Concept 9.1)

glucose ... oxygen

Most of the NADH that delivers electrons to the electron transport chain comes from which of the following processes? (eText Concept 9.3)

the citric acid cycle

The overall efficiency of respiration (the percentage of the energy released that is saved in ATP) is approximately _____. (eText Concept 9.4)

35%

Which of the following best describes the electron transport chain? (eText Concept 9.4)

Electrons are passed from one carrier to another, releasing a little energy at each step.

A gram of fat oxidized by respiration produces approximately twice as much ATP as a gram of carbohydrate. Which of the following best explains this observation? (eText Concept 9.6)

Fats are better electron donors to oxygen than are sugars.

If significant amounts of materials are removed from the citric acid cycle to produce amino acids for protein synthesis, which of the following will result? (eText Concept 9.6)

IDK

Which process is the one in which glucose is oxidized to generate two molecules of pyruvate, and in which ATP and NADH are produced? (eText Concept 9.1)

IDK

If muscle cells in the human body consume O2 faster than it can be supplied, which of the following is likely to result? (eText Concept 9.5)

IDK Correct. Muscle cells would not be able to produce enough ATP to meet demands, oxidative phosphorylation would stop, and muscle cells would consume glucose at an increased rate.

Each ATP molecule contains about 1% of the amount of chemical energy available from the complete oxidation of a single glucose molecule. Cellular respiration produces about 32 ATP from one glucose molecule. What happens to the rest of the energy in glucose? (eText Concept 9.1)

It is converted to heat.

In glycolysis in the absence of oxygen, cells need a way to regenerate which compound? (eText Concept 9.5)

NAD+

the flow of H+ across the inner mitochondrial membrane through the ATP synthase enzyme

NAD+ and FAD are not available for glycolysis and the citric acid cycle to continue.

After completion of the citric acid cycle, most of the usable energy from the original glucose molecule is in the form of _____. (eText Concept 9.3)

NADH

If a compound that allows protons to freely diffuse across membranes is added to cells that are actively metabolizing glucose via cellular respiration, which of the following processes would stop? (eText Concept 9.4)

None of the listed responses is correct.

In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs? (eText Concept 9.3)

Pyruvate is oxidized and decarboxylated, and the removed electrons are used to reduce an NAD+ to an NADH.

Which of the following statements is the best explanation of what happens to the temperature and carbon dioxide concentration during a one-hour class period in a classroom of 300 students if the heating and air conditioning is turned off and all doors are kept closed? (eText Concept 9.1)

Temperature and the level of carbon dioxide rise as heat and carbon dioxide are by-products of cellular respiration.

Which of the following substances is/are involved in oxidative phosphorylation? (eText Concept 9.4)

The first three listed responses are involved in oxidative phosphorylation.

Most of the electrons removed from glucose by cellular respiration are used for which of the following processes? (eText Concept 9.4)

The first two choices are correct.

Why is the citric acid cycle called a cycle? (eText Concept 9.3)

The four-carbon acid that accepts the acetyl CoA in the first step of the cycle is regenerated by the last step of the cycle.

In glycolysis, there is no production of carbon dioxide as a product of the pathway. Which of the following is the best explanation for this? (eText Concept 9.2)

The products of glycolysis contain the same total number of carbon atoms as in the starting material.

When solid tumors of animals reach a certain size, the center of the tumor begins to die. To prevent this, the tumor can recruit new blood vessels. What purpose does the recruitment of blood vessels to growing tumors serve? (eText Concept 9.4)

The second and third explanations together represent the best answer.

When protein molecules are used as fuel for cellular respiration, _____ are produced as waste. (eText Concept 9.6)

amino groups

During aerobic respiration, molecular oxygen (O2) is used for which of the following purposes? (eText Concept 9.4)

at the end of the electron transport chain to accept electrons and form H2O

Where do the reactions of glycolysis occur in a eukaryotic cell? (eText Concept 9.1)

cytosol

In an experiment, mice were fed glucose (C6H12O6) containing a small amount of radioactive oxygen. The mice were closely monitored, and after a few minutes radioactive oxygen atoms showed up in _____. (eText Concept 9.3)

carbon dioxide

Which of the following is the source of the energy that produces the chemiosmotic gradient in mitochondria? (eText Concept 9.4)

electrons moving down the electron transport chain

Fermentation is essentially glycolysis plus an extra step in which pyruvate is reduced to form lactate or alcohol and carbon dioxide. This last step _____. (eText Concept 9.5)

enables the cell to recycle the reduced NADH to oxidized NAD+

The function of cellular respiration is to _____. (eText Concept 9.1)

extract usable energy from glucose

Which of the following represents the major (but not the only) energy accomplishment of the citric acid cycle? (eText Concept 9.3)

formation of NADH and FADH2

How many molecules of ATP are gained by substrate-level phosphorylation from the complete breakdown of a single molecule of glucose in the presence of oxygen? (eText Concept 9.3)

four

Of the following molecules in the glycolytic pathway (the process of glycolysis), the one with the most chemical energy is _____. (eText Concept 9.2)

fructose-1,6-bisphosphate

Of the metabolic pathways listed below, which is the only pathway found in all organisms? (eText Concept 9.5)

glycolysis

A chemist has discovered a drug that blocks phosphoglucoisomerase, an enzyme that catalyzes the second reaction in glycolysis. He wants to use the drug to kill bacteria in people with infections. However, he cannot do this because _____. (eText Concept 9.2)

human cells must also perform glycolysis; the drug might also poison them

During respiration in eukaryotic cells, the electron transport chain is located in or on the _____. (eText Concept 9.4)

inner membrane of the mitochondrion

Sports physiologists at an Olympic training center wanted to monitor athletes to determine at what point their muscles were functioning anaerobically. They could do this by checking for a buildup of which of the following compounds? (eText Concept 9.5)

lactate

A molecule becomes more oxidized when it _____. (eText Concept 9.1)

loses an electron

Which of the following is a correct description of the events of cellular respiration and the sequence of events in cellular respiration? (eText Concept 9.1)

oxidation of glucose to pyruvate; oxidation of pyruvate; oxidation of acetyl-coA; oxidative phosphorylation

Most of the ATP produced in cellular respiration comes from which of the following processes?

oxidative phosphorylation

During the reaction C6H12O6 + 6 O2 → 6 CO2 + 6 H2O, which compound is reduced as a result of the reaction (eText Concept 9.1)

oxygen

The energy given up by electrons as they move through the electron transport chain is used in which of the following processes? (eText Concept 9.4)

pumping H+ across a membrane

Muscle tissues make lactate from pyruvate to do which of the following? (eText Concept 9.5)

regenerate NAD+

Which of the following accompanies the conversion of pyruvate to acetyl CoA before the citric acid cycle? (eText Concept 9.3)

release of CO2 and synthesis of NADH

Which part of the catabolism of glucose by cellular respiration requires molecular oxygen (O2) and produces CO2? (eText Concept 9.4)

the combination of the citric acid cycle and electron transport

The ATP synthase in a human cell obtains energy for synthesizing ATP directly from which of the following processes? (eText Concept 9.4)

the flow of H+ across the inner mitochondrial membrane through the ATP synthase enzyme

Where do the reactions of the citric acid cycle occur in eukaryotic cells? (eText Concept 9.3)

the matrix of the mitochondrion

Oxygen gas (O2) is one of the strongest oxidizing agents known. The explanation for this is that _____. (eText Concept 9.1)

the oxygen atom is very electronegative

In brewing beer, maltose (a disaccharide of glucose) is _____. (eText Concept 9.5)

the substrate for alcoholic fermentation

A small amount of ATP is made in glycolysis by which of the following processes? (eText Concept 9.1)

transfer of a phosphate group from a fragment of glucose to ADP by substrate-level phosphorylation

In the citric acid cycle, for each pyruvate that enters the cycle, one ATP, three NADH, and one FADH2 are produced. For each glucose molecule that enters glycolysis, how many ATP, NADH, and FADH2 are produced in the citric acid cycle? (eText Concept 9.3)

two ATP, six NADH, two FADH2