AP Biology Chapter 9

The synthesis of ATP by oxidative phosphorylation, using the energy released by movement of protons across the membrane down their electrochemical gradient, is an example of which of the following processes? A) Active transport B) A reaction with a positive delta G C) allosteric regulation D) coupling of an endergonic reaction to an exergonic reaction

A reaction with a positive delta G

Water is one of the end products of aerobic respiration. What is the source of the oxygen atom used in the formation of the water? A) carbon dioxide (CO2) B) glucose (C6H12O6) C) pyruvate (C3H3O3-) D) molecular oxygen (O2)

Molecular oxygen (O2)

What is the oxidizing agent in the following reaction? Pyruvate + NADH + H+ -> Lactate + NAD+ A) NAD+ B) NADH C) lactate D) pyruvate

Pyruvate

If glucose is the soul energy source, what fraction of the carbon dioxide exhaled by animals is generated only by the reactions involved in oxidation of pyruvate to acetyl CoA? A) 2/3 B) 1/3 C) 1/6 D) all of it

1/3

Substrate-level phosphorylation accounts for approximately what percentage of the ATP formed by the reactions of glycolysis? A) 38% B) 2% C) 100% D) 0%

100%

Starting with one molecule of glucose, glycolysis results in the net production of which of the following sets of energy-containing products? A) 4 NADH, 2 pyruvate, and 4 ATP B) 6 C02, 2 pyruvate, and 2 ATP C) 2 NAD+, 2 pyruvate, and 2 ATP D) 2NADH, 2 pyruvate, and 2 ATP

2NADH, 2 pyruvate, and 2 ATP

Starting with citrate, which of the following combinations of products would result from three acetyl CoA molecules entering the citric acid cycle? A) 6 ATP, 6 CO2, 3 NADH, and 12 FADH2 B) 3 ATP, 3 CO2, 3 NADH, and 3 FADH2 C) 3 ATP, 6 CO2, 9 NADH, and 3 FADH2 D) 1 ATP, 2 CO2, 3 NADH, and 1 FADH2

3 ATP, 6 CO2, 9 NADH, and 3 FADH2

Approximately how many molecules of ATP are produced from the complete oxidation of one molecule of glucose in aerobic cellular respiration? A) 4 B) 2 C) 30-32 D) 18-24

30-32

For each mole of glucose oxidized by cellular respiration, how many moles of CO2 are released in the citric acid cycle? A) 6 B) 32 C) 2 D) 4

6

In the absence of oxygen, yeast cells can obtain energy by fermentation, which results in the production of which of the following sets of molecules? A) ATP, CO2, and lactate B) ATP, NADH, and ethanol C) ATP, CO2, and acetyl CoA D) ATP, CO2, and ethanol (ethyl alcohol)

ATP, CO2, and ethanol (ethyl alcohol)

Which of the following is formed by the removal of a carbon (as CO2) from a molecule of pyruvate? A) acetyl CoA B) citrate C) water D) ATP

Acetyl CoA

Which of the following statements below describes the results of the following reaction? C6H12O6 + 6O2 -> 6CO2 + 6H2O + Energy A) CO2 is reduced and O2 is oxidized B) O2 is oxidized and H2O is reduced C) O2 is reduced and CO2 is oxidized D) C6H12O6 is oxidized and O2 is reduced

C6H12O6 is oxidized and O2 is reduced

In chemiosmosis, what is the most direct source of energy that is used to convert ADP+Pi to ATP? A) Energy released from movement of protons through ATP synthase, down their electrochemical gradient B) Energy released as electrons flow through the electron transport chain C) Energy released from substrate level phosphorylation D) Energy released as electrons are transferred across the inner mitochondrial membrane

Energy released from movement of protons through ATP synthase, down their electrochemical gradient

During aerobic respiration, which of the following molecules directly donates electrons to the electron transport chain at the lowest energy level? A) FADH2 B) water C) ATP D) NADH

FADH2

In which reactions of cellular respiration and fermentation does substrate-level phosphorylation occur? A) only in the citric acid cycle B) only in glycolysis C) only in the electron transport chain D) in both glycolysis and the citric acid cycle

In both glycolysis and the citric acid cycle

Which of the following statements describes what happens to a molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction? A) it loses electrons and gains potential energy B) it gains electrons and loses potential energy C) it loses electrons and loses potential energy D) it gains electrons and gains potential energy

It loses electrons and loses potential energy

Which of the following statements about NAD+ is true? A) NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle. B) NAD+ has more chemical energy than NADH C) in the absence of NAD+, glycolysis can still function D) NAD+ can donate electrons for use in oxidative phosphorylation

NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle.

Following glycolysis and the citric acid cycle, but before the electron transport chain and oxidative phosphorylation, the carbon skeleton of glucose has been broken down to CO2 with some net gain of ATP. Most of the energy from the original glucose molecule at that point in the process, however, is stored in the form of which of the following molecules? A) NADH B) acetyl-CoA C) NAD+ D) pyruvate

NADH

Which electron carrier(s) function in the citric acid cycle? A) NADH and FADH2 B) The electron transport chain C) ADP and ATP D) NAD+ only

NADH and FADH2

If pyruvate oxidation is blocked what will happen to the levels of oxaloacetate and citric acid in the citric acid cycle shown in the accompanying figure? A) Oxaloacetate will accumulate and citric acid will decrease B) both oxaloacetate and citric acid will decrease C) both oxaloacetate and citric acid will accumulate D) Oxaloacetate will decrease and citric acid will accumulate

Oxaloacetate will accumulate and citric acid will decrease

When a molecule of NAD+ (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a proton), the molecule becomes____. A) reduced B) dehydrogenated C) oxidized D) redoxed

Reduced

During which of the following metabolic processes is most of the CO2 from the catabolism of glucose released? A) The citric acid cycle B) electron transport C) glycolysis D) oxidation of pyruvate to acetyl CoA

The citric acid cycle

What happens to a glucose molecule when it loses a hydrogen atom as the result of an oxidation-reduction reaction? A) the glucose molecule is oxidized B) the glucose molecule is hydrolyzed C) the glucose molecule is an oxidizing agent D) the glucose molecule is reduced

The glucose molecule is oxidized

Which of the following events takes place in the electron transport chain? A) The breakdown of glucose into six carbon dioxide molecules B) The breakdown of an acetyl group to carbon dioxide C) substrate-level phosphorylation D) The harnessing of energy from high energy electrons derived from glycolysis and the citric acid cycle

The harnessing of energy from high energy electrons derived from glycolysis and the citric acid cycle

If you were to add one of the eight citric acid cycle intermediates to the culture medium of yeast growing in the laboratory, what would you think would happen to the rates of ATP and carbon dioxide production? A) The rate of ATP production will increase, but the rate of carbon dioxide production would decrease B) there would be no change in ATP production, but the rate of carbon dioxide production would increase C) The rates of ATP production and carbon dioxide production would both increase D) The rates of ATP and carbon dioxide production would both decrease

The rates of ATP production and carbon dioxide production would both increase

The oxygen consumed during cellular respiration is directly involved in which of the following processes or events? A) accepting electrons at the end of the electron transport chain B) glycolysis C) The citric acid cycle D) oxidation of pyruvate to acetyl CoA

accepting electrons at the end of the electron transport chain

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. Which of the following sets of products result from these reactions? A) acetyl CoA, NADH, and CO2 B) acetyl CoA, FADH2, and CO2 C) acetyl CoA, NAD+, ATP, and CO2 D) acetyl CoA, O2, and ATP

acetyl CoA, NADH, and CO2

Which kind of metabolic poison would most directly interfere with glycolysis? A) an agent that reacts with NADH and oxidizes it to NAD+ B) an agent that binds to pyruvate and inactivates it C) an agent that closely mimics the structure of glucose but is not metabolized D) an agent that reacts with oxygen and depletes its concentration in the cell

an agent that closely mimics the structure of glucose but is not metabolized

A cell has enough available ATP to meet its needs for about 30 seconds. What is likely to happen when an athlete exhausts his or her ATP supply? A) other cells take over and the muscle cells that have used up their ATP cease to function B) he or she has to sit down and rest C) ATP is transported into the cell from the circulatory system D) catabolic processes are activated to generate more ATP

catabolic processes are activated to generate more ATP

Yeast cells that have defective mitochondria incapable of respiration will be able to grow by catabolizing which of the following carbon sources of energy? A) fatty acids B) amino acids C) cholesterol D) glucose

glucose

Which of the following sequences describes the path by which electrons travel downhill energetically in aerobic respiration? A) food-> glycolysis-> citric acid cycle-> NADH-> ATP B) glucose-> NADH-> electron transport chain-> oxygen C) glucose-> pyruvate-> electron transport chain-> NADH-> ATP D) glucose-> pyruvate-> ATP-> oxygen

glucose-> pyruvate-> electron transport chain-> NADH-> ATP

Which of the following metabolic processes normally occurs regardless of whether or not oxygen is present? A) citric acid cycle B) lactate fermentation C) oxidative phosphorylation D) glycolysis

glycolysis

Which of the following metabolic processes take place in the cytosol of a eukaryotic cell? A) fermentation and chemiosmosis B) glycolysis and fermentation C) oxidation of pyruvate to acetyl CoA D) citric acid cycle

glycolysis and fermentation

Which of the following statements about the electron transport chain is true? A) it is driven by ATP hydrolysis B) it consist of a series of redox reactions C) it includes a series of hydrolysis reactions associated with mitochondrial membranes D) it occurs in the cytoplasm of both prokaryotic and eukaryotic cells

it consist of a series of redox reactions

Why is glycolysis considered to be one of the first metabolic pathways to have evolved? A) it requires the presence of membrane-enclosed cell organelles found only in eukaryotic cells B) it produces much less ATP than does oxidative phosphorylation C) it is present in prokaryotic cells but not in eukaryotic cells D) it does not involve organelles or specialized structures, does not require oxygen, and is present in most organisms

it does not involve organelles or specialized structures, does not require oxygen, and is present in most organisms

In liver cells, the inner mitochondrial membranes are about five times the area of the outer mitochondrial membrane's. What purpose must this serve? A) it increases the surface for oxidative phosphorylation B) it allows for an increased rate of glycolysis C) it increases the surface for substrate level phosphorylation D) it allows for an increased rate of the citric acid cycle

it increases the surface for oxidative phosphorylation

An organism is discovered that thrives in both the presence and absence of oxygen. Interestingly as oxygen is removed from the organisms environment, the rate of sugar consumption increases while the growth rate decreases. What do these observations suggest about the likely identity of this organism? A) it is an unremarkable eukaryotic organism B) it is an obligate anaerobic organism C) it is a facultative anaerobic organism D) it is a photosynthetic organism

it is an obligate anaerobic organism

Which of the following statements best describes the primary role played by oxygen in cellular respiration? A) it serves as an acceptor for carbon, forming CO2 in the citric acid cycle B) it yields energy in the form of ATP as it is passed down the electron transport chain C) it oxidizes glucose to form two molecules of pyruvate D) it serves as the final acceptor for electrons from the electron transport chain

it serves as the final acceptor for electrons from the electron transport chain

A person on a strict diet and exercise regimen lost 7 kg (about 15 pounds) of body fat in just two weeks. What is the most likely way that the lost fat left the body? A) it was eliminated from the body as feces B) it was converted to ATP, which weighs much less than fat C) it was released as CO2 and H2O D) it was converted to heat and then released

it was released as CO2 and H2O

Where are the proteins of the electron transport chain located? A) mitochondrial outer membrane B) mitochondrial inner membrane C) mitochondrial matrix D) mitochondria intermembrane space

mitochondrial inner membrane

Energy released by the electron transport chain is used to pump H+ ions into which location in eukaryotic cells? A) mitochondrial intermembrane space B) cytoplasm adjacent to the mitochondrial outer membrane C) mitochondrial inner membrane D) mitochondrial matrix

mitochondrial intermembrane space

The free energy for the oxidation of glucose to CO2 and water is -686 kcal/mole, and the free energy for the reduction of energy to NADH is +53 kcal/ mole. Why are only two molecules of NADH formed during glycolysis when it appears that as many as a dozen could be formed? A) most of the free energy available from the oxidation of glucose is used in the production of ATP in glycolysis B) there is no CO2 or water produced as products of glycolysis C) most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis D) glycolysis is a very insufficient reaction, with much of the energy of glucose released as heat.

most of the free energy available from the oxidation of glucose remains in pyruvate, one of the products of glycolysis

What kinds of cells carry out ATP synthesis by chemiosmosis? A) all cells, both prokaryotic and eukaryotic, exclusively using oxygen as the electron acceptor B) all respiring cells, both prokaryotic and eukaryotic, using either oxygen or other electron acceptors C) only eukaryotic cells, both plant and animal, using their oxygen or other electron acceptors D) only animal cells and mitochondria, exclusively using oxygen as the electron acceptor

only eukaryotic cells, both plant and animal ,using their oxygen or other electron acceptors

Carbon dioxide is released during which of the following stages of cellular respiration? A) oxidation of pyruvate to acetyl CoA and the citric acid cycle B) fermentation and glycolysis C) glycolysis and the oxidation of pyruvate to acetyl CoA D) oxidative phosphorylation and fermentation

oxidation of pyruvate to acetyl CoA and the citric acid cycle

Which of the following processes is driven by chemiosmosis? A) ATP hydrolysis B) oxidative phosphorylation C) substrate-level phosphorylation D) reduction of NAD+ to NADH

oxidative phosphorylation

Which of the following processes generates a proton-motive force in mitochondria? A) The flow of protons through ATP synthase down there concentration gradient B) pumping of hydrogen ions from the mitochondrial matrix across the inner membrane and into the intermembrane space C) lowering of pH in the mitochondrial matrix D) The reduction of NAD+ by the first electron carrier in the electron transport chain

pumping of hydrogen ions from the mitochondrial matrix across the inner membrane and into the intermembrane space

Which of the following statements describes a primary function of both alcohol fermentation and lactic acid fermentation? A) reduction of FAD to FADH2 B) Hydrolysis of ATP to ADP+Pi C) oxidation of NADH to NAD+ D) reduction of NAD+ to NADH

reduction of NAD+ to NADH

Why are carbohydrates and fats frequently considered high energy foods? A) they contain no nitrogen atoms B) they are strong oxidizing molecules C) they contain many oxygen atoms D) they contain many electrons associated with hydrogen atoms

they contain many electrons associated with hydrogen atoms

In glycolysis, for each molecule of glucose oxidized to pyruvate,____. A) four molecules of ATP are used, and two molecules of ATP are produced B) two molecules of ATP are used, and four molecules of ATP are produced C) two molecules of ATP are used, and two molecules of ATP are produced D) two molecules of ATP are used, and six molecules of ATP are produced

two molecules of ATP are used, and four molecules of ATP are produced