AP Biology Chapter 9 Questions Study Guide

Successfully making cheese requires separating what? curds and whey carbohydrates and proteins rennet and bacteria fats and salts

curds and whey

Which step of the cellular respiration pathway can take place in the absence of oxygen? Hints Krebs cycle Electron transport chain Glycolysis Fermentation

Glycolysis

True or false? The potential energy in an ATP molecule is derived mainly from its three phosphate groups. Hints True False

True

Which terms describe two atoms when they form a bond in which electrons are completely transferred from one atom to the other? Hints Ionic and covalent. Polar and nonpolar. Anion and cation. Proton and electron.

anion and cation

Where are the proteins of the electron transport chain located? a. mitochondrial matrix b. mitochondrial inner membrane c. mitochondrial intermembrane space d. mitochondrial outer membrane

mitochondrial inner membrane

Acetyl CoA combines with _______ to form _______ in the first step of the citric acid cycle.

oxaloasetate; citrate

In glycolysis, ATP molecules are produced by _____. cellular respiration substrate-level phosphorylation photosynthesis photophosphorylation oxidative phosphorylation

substrate-level phosphorylation

In the citric acid cycle, ATP molecules are produced by _____. substrate-level phosphorylation photophosphorylation cellular respiration photosynthesis oxidative phosphorylation

substrate-level phosphorylation

How many of the following are produced per Acetyl CoA that enters the citric acid cycle? How would these numbers change if I asked per glucose? a. ATP b. NADH c. FADH2 d. CO2

1,3,1,2 per glucose 2,6,2,4

For every FADH2 that enters the ETC _____ ATP are produced.

2

How many NADH are produced by glycolysis? 3 1 5 4 2

2

In glycolysis there is a net gain of _____ ATP. 3 1 5 4 2

2

Starting with one molecule of glucose, the energy-containing products of glycolysis are _____. 2 NADH, 2 pyruvate, and 2 ATP 2 FADH2, 2 pyruvate, and 4 ATP 2 NAD+, 2 pyruvate, and 2 ATP 6 CO2, 2 pyruvate, and 2 ATP

2 NADH, 2 pyruvate, and 2 ATP

For every NADH that enters the ETC _____ ATP are produced.

3

Approximately how many molecules of ATP are produced from the complete oxidation of one molecule of glucose (C6H12O6) in aerobic cellular respiration? 4 2 30-32 18-24

30-32

In glycolysis, what starts the process of glucose oxidation? hexokinase NADPH ATP ADP FADH2

ATP

What molecule enters the citric acid cycle?

Acetyl CoA

Into which molecule are all the carbon atoms in glucose ultimately incorporated during cellular respiration? Hints ATP NADH Water Carbon dioxide

Carbon Dioxide

The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the a. affinity of oxygen for electrons. b. oxidation of glucose and other organic compounds. c. flow of electrons down the electron transport chain. d. H+ concentration across the membrane holding ATP synthase. e. transfer of phosphate to ADP.

D. H+ concentration across the membrane holding ATP synthase.

Which stage of glucose metabolism produces the most ATP? Hints Krebs cycle Electron transport and chemiosmosis Fermentation of pyruvate to lactate Glycolysis

Electron transport and chemiosmosis

During aerobic respiration, which of the following directly donates electrons to the electron transport chain at the lowest energy level? FADH2 NADH ATP ADP + i

FADH2

Which of these is NOT a product of glycolysis? ATP FADH2 NADH pyruvate

FADH2

What is the difference between the last two questions

FADH2 starts giving up electrons at the second protein not the first like NADH. FADH2 starts later.

When oxygen is not present many organisms resort to just glycolysis for ATP production. What process takes place to ensure the cell does not run out of NAD+ for glycolysis?

Fermentation

Which process is not part of the cellular respiration pathway that produces large amounts of ATP in a cell? Hints Fermentation Krebs cycle Glycolysis Electron transport chain

Fermentation

Which molecule is metabolized in a cell to produce energy "currency" in the form of ATP? Hints ADP Phosphate Carbon dioxide Glucose

Glucose

As electron move from one protein to another ________ are pumped into the ________ of the mitochondria.

H+; inner membrane space

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 in the form of _____. pyruvate NADH glucose acetyl-CoA

NADH

What is the final electron acceptor in cellular respiration?

O2

True or false? The reactions that generate the largest amounts of ATP during cellular respiration take place in the mitochondria. Hints True False

True

Carbohydrates and fats are considered high-energy foods because they _____. a. have a lot of electrons associated with hydrogen. b. have no nitrogen in their makeup. c. are easily reduced. d. have a lot of oxygen atoms.

a.

In most cells, not all of the carbon compounds that participate in glycolysis and the citric acid cycle are converted to carbon dioxide by cellular respiration. What happens to the carbon in these compounds that does not end up as CO2? Hints a. The carbon compounds are removed from these processes to serve as building blocks for other complex molecules. b. They are used to make NADH. c. They are used to make ATP from NADH. d. These carbon compounds are used to convert ADP to ATP via chemiosmosis. e. They are converted to heat energy.

a.

Select the correct statement about cellular respiration. a. Cellular respiration and breathing differ in that cellular respiration is at the cellular level, whereas breathing is at the organismal level. b. Animals carry out cellular respiration whereas plants carry out photosynthesis. c. Plants carry out cellular respiration only in organs such as roots that cannot carry out photosynthesis.

a.

The chemiosmotic hypothesis is an important concept in our understanding of cellular metabolism in general because it explains _____. a. how ATP is synthesized by a proton motive force b. how electron transport can fuel substrate-level phosphorylation c. the sequence of the electron transport chain molecules d. the reduction of oxygen to water in the final steps of oxidative metabolism

a.

The electron transport chain _____. a. is a series of redox reactions b. is a series of substitution reactions c. takes place in the cytoplasm of prokaryotic cells d. is driven by ATP consumption

a.

The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction _____. a. loses electrons and loses potential energy b. gains electrons and loses potential energy c. loses electrons and gains potential energy d. gains electrons and gains potential energy

a.

When electrons move closer to a more electronegative atom, what happens? The more electronegative atom is _____. a. reduced, and energy is released b. oxidized, and energy is consumed c. reduced, and energy is consumed d. oxidized, and energy is released

a.

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+ can donate electrons for use in oxidative phosphorylation. c. NAD+ has more chemical energy than NADH. d. In the absence of NAD+, glycolysis can still function.

a.

The enzyme in the previous question is a. inhibited by what two molecules? b. stimulated by what molecule?

a. ATP and Citrate b. AMP

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule? a. glycolysis b. the electron transport chain c. reduction of pyruvate to lactate d. synthesis of acetyl CoA from pyruvate e. the citric acid cycle

a. glycolysis

Which of these enters the citric acid cycle? glucose acetyl CoA NADH + H+ pyruvate G3P

acetyl CoA

Which of these is NOT a product of the citric acid cycle? FADH2 ATP acetyl CoA CO2 NADH + H+

acetyl CoA

Which one of the following is formed by the removal of a carbon (as CO2) from a molecule of pyruvate? acetyl CoA glyceraldehyde 3-phosphate citrate oxaloacetate

acetyl CoA

A glucose molecule is completely broken down to carbon dioxide and water in glycolysis and the citric acid cycle, but together these two processes yield only a few molecules of ATP. What happened to most of the energy that the cell obtains from the oxidation of glucose? Hints a. It is stored in pyruvate. b. It is stored in NADH and FADH2 c. It was lost as heat. d. It is stored in the ATP that was formed by glycolysis and the citric acid cycle. e. It is stored in the carbon dioxide and water molecules released by these processes.

b.

Chemiosmotic ATP synthesis (oxidative phosphorylation) occurs in _____. a. only in mitochondria, using either oxygen or other electron acceptors b. all respiring cells, both prokaryotic and eukaryotic, using either oxygen or other electron acceptors c. all cells, but only in the presence of oxygen d. only eukaryotic cells, in the presence of oxygen

b.

Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic cells? a. mitochondrial inner membrane b. mitochondrial intermembrane space c. mitochondrial matrix d. mitochondrial outer membrane

b.

How will a healthy individual's ATP production change during an eight-hour fast? a. The individual's ATP production will decrease significantly. b. The individual's ATP production will not change significantly. c. The individual's ATP production will increase significantly.

b.

In mitochondria, exergonic redox reactions a. are coupled via phosphorylated intermediates to endergonic processes. b. provide the energy that establishes the proton gradient. c. are directly coupled to substrate-level phosphorylation. d. are the source of energy driving prokaryotic ATP synthesis. e. reduce carbon atoms to carbon dioxide.

b.

Which of the following best describes the main purpose of the combined processes of glycolysis and cellular respiration? Hints a. breaking down ATP, so that ADP and P can be reused b. transforming the energy in glucose and related molecules in a chemical form that cells can use for work c. producing complex molecules from chemical building blocks d. catabolism of sugars and related compounds e. the breakdown of glucose to carbon dioxide and water

b.

Which of the following describes the process of glycolysis? Hints a. It requires ATP and NADH. b. It represents the first stage in the chemical oxidation of glucose by a cell. c. It converts one glucose molecule to two molecules of pyruvate and carbon dioxide. d. Glycolysis produces 30 ATP from each molecule of glucose. e. Glycolysis occurs in the mitochondria.

b.

Which of the following events takes place in the electron transport chain? a. the breakdown of glucose into two pyruvate molecules b. the extraction of energy from high-energy electrons remaining from glycolysis and the citric acid cycle c. the breakdown of an acetyl group to carbon dioxide d. substrate-level phosphorylation

b.

Which of the following is true? a. A high fat cheese is more dense than a low fat cheese. b. A high fat cheese is less dense than a low fat cheese. c. Fat content is not related to density in cheese. d. All cheeses have equal densities.

b.

Which of the following normally occurs regardless of whether or not oxygen (O2) is present? a. oxidative phosphorylation (chemiosmosis) b. glycolysis c. fermentation d. citric acid cycle

b.

Which of the following statements is not true of most cellular redox reactions? Hints a. The electron acceptor is reduced. b. A hydrogen atom is transferred to the atom that loses an electron. c. The reactant that is oxidized loses electrons. d. Changes in potential energy can be released as heat.

b.

Which statement about the citric acid cycle is correct? Hints a. The citric acid cycle produces most of the ATP that is subsequently used by the electron transport chain. b. The last reaction in the citric acid cycle produces a product that is a substrate for the first reaction of the citric acid cycle. c. The citric acid cycle depends on the availability of NAD+, which is a product of glycolysis. d. The citric acid cycle oxidizes glucose to carbon dioxide. e. The oxidation of compounds by the citric acid cycle requires molecular oxygen.

b.

What is the oxidizing agent in the following reaction? Pyruvate + NADH + H+ → Lactate + NAD+ a. NAD+ b. pyruvate c. NADH d. oxygen e. lactate

b. pyruvate

When electrons flow along the electron transport chains of mitochondria, which of the following changes occurs? a. The electrons gain free energy. b. The pH of the matrix increases. c. The cytochromes phosphorylate ADP to form ATP. d. NAD+ is oxidized. e. ATP synthase pumps protons by active transport.

b. the ph of the matrix increases

You are a cheese maker wanting to connect a large quantity of lactose to acid. Which of the following do you need? bacteria potassium chloride rennet hydrocolloids

bacteria

In respiration, beta oxidation involves the _____. breakdown of fatty acids regulation of glycolysis oxidation of pyruvate oxidation of glucose

breakdown of fatty acids

Carbon dioxide (CO2) is released during which of the following stages of cellular respiration? a. fermentation and glycolysis b. glycolysis and the oxidation of pyruvate to acetyl CoA c. oxidation of pyruvate to acetyl CoA and the citric acid cycle d. oxidative phosphorylation and fermentation

c.

Identify all correct statements about the basic function of fermentation. Select all that apply. a. The basic function of fermentation is the production of ethyl alcohol or lactic acid. b. The basic function of fermentation is the production of additional ATP by further oxidation of the products of glycolysis. c. The basic function of fermentation is the regeneration of NAD+, which allows continued ATP production by glycolysis.

c.

In cellular respiration, a series of molecules forming an electron transport chain alternately accepts and then donates electrons. What is the advantage of such an electron transport chain? a. The advantage of the respiratory electron transport chain is that oxygen is the final electron acceptor. b. The advantage of an electron transport chain is the production of a large number of reduced, high-energy intermediates. c. The advantage of an electron transport chain is that a small amount of energy is released with the transfer of an electron between each pair of intermediates.

c.

In muscle cells, fermentation produces _____. a. carbon dioxide, ethanol, NADH, and ATP b. lactate, NADH, and ATP c. lactate and NAD+ d. carbon dioxide, ethanol, and NAD+ e. pyruvate

c.

New biosensors, applied like a temporary tattoo to the skin, can alert serious athletes that they are about to "hit the wall" and find it difficult to continue exercising. These biosensors monitor lactate, a form of lactic acid, released in sweat during strenuous exercise. Which of the statements below is the best explanation of why athletes would need to monitor lactate levels? a. During aerobic respiration, muscles cells produce too much lactate which causes a rise in the pH of the muscle cells, thus athletes must consume increased amounts of sports drinks, high in electrolytes, to buffer the pH. b. During aerobic respiration, muscle cells cannot produce enough lactate to fuel muscle cell contractions and muscles begin to cramp, thus athletic performance suffers. c. During anaerobic respiration, lactate levels increase when muscles cells need more energy, however muscles cells eventually fatigue, thus athletes should modify their activities to increase aerobic respiration. d. During anaerobic respiration, muscle cells receive too little oxygen and begin to convert lactate to pyruvate (pyruvic acid), thus athletes experience cramping and fatigue.

c.

Substrate-level phosphorylation occurs _____. a. in the citric acid cycle b. during oxidative phosphorylation c. in both glycolysis and the citric acid cycle d. in glycolysis

c.

When hydrogen ions are pumped from the mitochondrial matrix across the inner membrane and into the intermembrane space, the result is the _____. a. lowering of pH in the mitochondrial matrix b. reduction of NAD+ c. creation of a proton-motive force d. formation of ATP

c.

Which of the following cheeses would likely spoil the most quickly? a. A low fat, high salt variety. b. A high fat, high salt variety. c. A low fat, low salt variety. d. A high fat, low salt variety.

c.

Which of the following occurs in the cytosol of a eukaryotic cell? a. fermentation and chemiosmosis b. citric acid cycle c. glycolysis and fermentation d. oxidation of pyruvate to acetyl CoA

c.

Which of the following statements about the chemiosmotic synthesis of ATP is correct? Hints a. The energy for production of ATP from ADP comes directly from a gradient of electrons across the inner mitochondrial membrane. b. Oxygen participates directly in the reaction that makes ATP from ADP and P. c. The chemiosmotic synthesis of ATP requires that the electron transport in the inner mitochondrial membrane be coupled to proton transport across the same membrane. d. The chemiosmotic synthesis of ATP occurs only in eukaryotic cells, because it occurs in mitochondria. e. Chemiosmotic ATP synthesis requires oxygen.

c.

Which of the following statements accurately describes the function of a metabolic pathway involved in cellular respiration? a. The function of the citric acid cycle is the transfer of electrons from pyruvate to NADH to O2. b. The function of the bonding of acetic acid to the carrier molecule CoA to form acetyl CoA is the reduction of glucose to acetyl CoA. c. The function of glycolysis is to begin catabolism by breaking glucose into two molecules of pyruvate, with a net yield of two ATP.

c.

Which of the listed statements describes the results of the following reaction? C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy a. O2 is oxidized and H2O is reduced. b. CO2 is reduced and O2 is oxidized. c. C6H12O6 is oxidized and O2 is reduced. d. O2 is reduced and CO2 is oxidized.

c.

You create a new variety of cheese that has very little water. Which of the following is true? a. It contains no fat. b. It is low in fat. c. It is quite high in fat. d. Its fat content is so low, it is immeasurable.

c.

In glycolysis, for each molecule of glucose oxidized to pyruvate _____. a. two molecules of ATP are used and six molecules of ATP are produced. b. four molecules of ATP are used and two 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 four molecules of ATP are produced.

d.

In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of _____. a. ATP, NADH, and pyruvate b. ATP, pyruvate, and acetyl CoA c. ATP, CO2, and lactate d. ATP, CO2, and ethanol (ethyl alcohol)

d.

The oxygen consumed during cellular respiration is involved directly in which process or event? a. the oxidation of pyruvate to acetyl CoA b. glycolysis c. the citric acid cycle d. accepting electrons at the end of the electron transport chain

d.

The primary role of oxygen in cellular respiration is to _____. a. yield energy in the form of ATP as it is passed down the respiratory chain b. combine with lactate, forming pyruvate c. combine with carbon, forming CO2 d. act as an acceptor for electrons and hydrogen, forming water

d.

Which of the following statements about the electron transport chain is true? Hints a. The electron transport chain is the first step in cellular respiration. b. Electrons gain energy as they move down the chain. c. Water is the last electron acceptor. d. NADH and FADH2 donate their electrons to the chain.

d.

Which of the following statements is true of the bonds in a water molecule? Hints a. There is equal sharing of the electrons between the oxygen atom and the two hydrogen atoms, and the net charge is zero. b. Oxygen acts as the electron acceptor and is oxidized. c. The electron in each hydrogen atom is completely transferred to the oxygen atom, and each hydrogen atom has a net charge of +1. d. Oxygen holds electrons more tightly than hydrogen does, and the net charge is zero.

d.

Which term describes the degree to which an element attracts electrons? Electronegativity. Reduction. Oxidation. Polarity.

electronegativity

In the absence of oxygen, what is the net gain of ATP for each glucose molecule that enters glycolysis? Hints a. none, because in the absence of oxygen, no ATP can be made b. none, because all of the available energy remains in either lactate or ethanol c. four ATP d. up to 30 ATP e. two ATP

e.

In the combined processes of glycolysis and cellular respiration, what is consumed and what is produced? Hints a. Water is consumed, and ATP is produced. b. Carbon dioxide is consumed, and water is produced. c. ATP is consumed, and oxygen is produced. d. Oxygen is consumed, and glucose is produced. e. Glucose is consumed, and carbon dioxide is produced.

e.

Which one of the following statements about the redox reactions of the electron transport chain is correct? a. The oxidation of NADH is directly coupled to the reduction of oxygen to water. b. The electron transport chain takes electrons from water and gives them to oxygen. c. NADH gains electrons in the initial reaction of the electron transport chain. d. The redox reactions of the electron transport chain are directly coupled with the synthesis of ATP. e. The redox reactions of the electron transport chain are directly coupled to the movement of protons across a membrane.

e.

Most CO2 from catabolism is released during a. oxidative phosphorylation. b. electron transport. c. lactate fermentation. d. glycolysis. e. the citric acid cycle.

e. the citric acid cycle

Gaseous hydrogen burns in the presence of oxygen to form water: 2H2 + O2 → 2H2 O + energy Which molecule is oxidized and what kind of bond is formed? Hints Hydrogen, nonpolar. Oxygen, nonpolar. Oxygen, polar. Hydrogen, polar.

hydrogen, polar

As you move from protein to protein in the ETC the electronegativity increases or decreases?

increases

What kind of bond is formed when lithium and fluorine combine to form lithium fluoride? Hints Nonpolar covalent. Ionic. Polar covalent. Redox.

ionic

Glycolysis is active when cellular energy levels are _____; the regulatory enzyme, phosphofructokinase, is _____ by ATP. high; inhibited low; activated high; activated low; inhibited

low; inhibited

Where does the citric acid cycle take place?

matrix of mitochondria

Protons flowing back into the ________ of the mitochondria flow through the _______ producing ATP.

matrix; ATP synthase

During aerobic respiration, H2O is formed. Where does the oxygen atom for the formation of the water come from? glucose (C6H12O6) carbon dioxide (CO2) molecular oxygen (O2) pyruvate (C3H3O3-)

molecular oxygen (O2)

When a glucose molecule loses a hydrogen atom as the result of an oxidation-reduction reaction, the molecule becomes _____. reduced oxidized hydrolyzed an oxidizing agent

oxidized

the final electron acceptor of the electron transport chain that functions in aerobic oxidative phosphorylation is NAD+. water. pyruvate. ADP. oxygen.

oxygen

Cellular respiration is regulated by the allosteric control of _______ in the process called ________.

phosphofructokinase; glycolysis

In order for chemiosmosis to take place an ______ must be established between the intermembrane space and the matrix of the mitochondria.

proton gradient

In fermentation _____ is reduced and _____ is oxidized. lactate ... ethanol NAD+ ... pyruvate NADH ... lactate lactate ... NADH pyruvate ... NADH

pyruvate...NADH

When a molecule of NAD+ (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a proton), the molecule becomes _____. redoxed reduced oxidized dehydrogenated

reduced

What is the basic structure of the electron transport chain?

series of protein embedded in inner membrane of mitochondria.

Most of the CO2 from the catabolism of glucose is released during _____. glycolysis electron transport chemiosmosis the citric acid cycle

the citric acid cycle

The electrons stripped from glucose in cellular respiration end up in which compound? Hints NADH water ATP oxygen carbon dioxide

water

Can a prokaryote carry out respiration? Explain anwser

yes, b/c of ETC ones with ETC not all but some