Chapter 7 learning curve activity

The final electron acceptor of the electron transport chain is: NAD+. cytochrome C. ATP synthase. coenzyme Q. oxygen.

oxygen

Which of the following does not occur during the third phase of glycolysis? oxygen consumption None of the answer options is correct. pyruvate production the transfer of high-energy electrons to NAD+ ATP synthesis

oxygen consumption

In eukaryotes, acetyl-CoA synthesis takes place in the: mitochondrial matrix. outer mitochondrial membrane. inner mitochondrial membrane. intermembrane space of mitochondria. cytoplasm.

mitochondrial matrix.

The citric acid cycle takes place in the: mitochondrial matrix. inner mitochondrial membrane. intermembrane space of mitochondria. cytoplasm. outer mitochondrial membrane.

mitochondrial matrix.

In what organelle is acetyl-CoA synthesis carried out in a cell? endoplasmic reticulum nucleus chloroplast mitochondrion Golgi apparatus

mitochondrion

During the citric acid cycle, the production of CO2 is a(n) _____ reaction coupled to the production of ____________. oxidation; GTP reduction;, NADH reduction; ATP oxidation; ATP oxidation; NADH

oxidation; NADH

The electron transport chain is part of: glycolysis. acetyl-CoA synthesis. fermentation. oxidative phosphorylation. the citric acid cycle.

oxidative phosphorylation.

In cellular respiration, glucose is _____ to CO2 and oxygen is _____ to water. deoxygenated; phosphorylated phosphorylated; deoxygenated oxidized; oxidized oxidized; reduced reduced; oxidized

oxidized; reduced

The _____ forms of the electron carriers NAD+/NADH and FADH/FADH2 have high potential energy. oxidized reduced phosphorylated carboxylated None of the answer options is correct.

reduced

Fermentation occurs in: only in bacteria, fungi, and plants. anaerobic organisms only. some aerobic organisms, such as yeast, even in the presence of oxygen.

some aerobic organisms, such as yeast, even in the presence of oxygen.

When a single pyruvate is converted to acetyl-CoA, the other products of the reaction are: FADH2 and ATP. ATP and NADH. NADH and CO2. CO2 and ATP. Pi and FADH2.

NADH and CO2.

The inputs to glycolysis do not include (select all correct choices): NADH. ADP. glucose. NAD+. Pi.

NADH.

The inputs to glycolysis do not include (select all correct choices): Pi. NADH. NAD+. ADP. glucose.

NADH.

Energy released by transferring electrons along the electron transport chain is stored as potential energy in the form of: ATP synthase. coenzyme Q. ATP. a proton gradient. redox couples.

a proton gradient.

When glucose is broken down in a cell, all of the energy it stores is released simultaneously, not in a stepwise process. true false

false

In which of the following organisms would you expect ethanol fermentation to occur? bacteria fungi animals plants fungi and plants

fungi and plants

in cellular respiration, oxygen: gains electrons and is an oxidizing agent. loses electrons and is a reducing agent. gains electrons and is a reducing agent. loses electrons and is an oxidizing agent. None of the answer options is correct.

gains electrons and is an oxidizing agent.

Oxidation is the gain of electrons. true false

false

Which of the following is not one of the net final products of glycolysis? two molecules of acetyl-CoA two molecules of pyruvate two molecules of NADH two molecules of ATP

two molecules of acetyl-CoA

At the end of glycolysis, the carbon molecules originally found in the starting glucose molecule are in the form of: four ATP molecules. one pyruvate molecule. two pyruvate molecules. two NADH molecules. two ATP molecules.

two pyruvate molecules.

Which best describes energy production during cellular respiration? A small amount of energy is produced by substrate level phosphorylation; most is produced by oxidative phosphorylation. A small amount of energy is produced by oxidative phosphorylation; most is produced by substrate level phosphorylation. An equal amount is produced by oxidative and substrate level phosphorylation. It depends on the organism. Some produce most of their energy by substrate level phosphorylation, and some produce most of their energy by oxidative phosphorylation. None of these answer options accurately describes energy production during cellular respiration.

A small amount of energy is produced by substrate level phosphorylation; most is produced by oxidative phosphorylation

Which best describes energy production during cellular respiration? A small amount of energy is produced by substrate level phosphorylation; most is produced by oxidative phosphorylation. A small amount of energy is produced by oxidative phosphorylation; most is produced by substrate level phosphorylation. An equal amount is produced by oxidative and substrate level phosphorylation. It depends on the organism. Some produce most of their energy by substrate level phosphorylation, and some produce most of their energy by oxidative phosphorylation. None of these answer options accurately describes energy production during cellular respiration.

A small amount of energy is produced by substrate level phosphorylation; most is produced by oxidative phosphorylation.

During the citric acid cycle: fuel molecules are completely reduced. ATP is synthesized by substrate level phosphorylation. high-energy electrons are removed from NAD+ and FADH. ATP is synthesized by oxidative phosphorylation.

ATP is synthesized by substrate level phosphorylation.

Which of the following statements is true regarding acetyl-CoA synthesis? Acetyl-CoA synthesis forms the same number of NADH (per glucose molecule) as glycolysis. Like glycolysis, acetyl-CoA synthesis is carried out in the mitochondria. Acetyl-CoA synthesis ends with the oxidation of an acetyl group, which forms CO2. Acetyl-CoA synthesis directly follows the citric acid cycle during cellular respiration.

Acetyl-CoA synthesis forms the same number of NADH (per glucose molecule) as glycolysis.

Which of the following statements is true regarding acetyl-CoA synthesis? Like glycolysis, acetyl-CoA synthesis is carried out in the mitochondria. Acetyl-CoA synthesis directly follows the citric acid cycle during cellular respiration. Acetyl-CoA synthesis forms the same number of NADH (per glucose molecule) as glycolysis. Acetyl-CoA synthesis ends with the oxidation of an acetyl group, which forms CO2.

Acetyl-CoA synthesis forms the same number of NADH (per glucose molecule) as glycolysis.

Recall that fatty acids (like palmitic acid) can yield substantially more ATP compared to glucose. Why doesn't aerobic respiration rely solely on fatty acids as energy sources, rather than glucose? Fatty acids cannot be used by some vital tissues in the human body, such as the brain. Fatty acids are rare in the environment and cannot be readily acquired from food sources. Beta-oxidation—where fatty acids are broken down—requires a great deal of ATP and is not an energy-efficient process for cells. Aerobic respiration usually does rely on fatty acids in other mammals; however, humans are unique due to their relatively recent appearance on Earth. Fatty acids cannot be used to generate acetyl-CoA, and so cannot tie into the later stages of aerobic respiration

Fatty acids cannot be used by some vital tissues in the human body, such as the brain.

imagine that a eukaryotic cell carries a mutation impairing its ability to phosphorylate glucose during glycolysis. What is a likely result of this mutation? Without the phosphorylation of glucose, glycolysis would consist entirely of exergonic reactions. Because phosphorylation stabilizes glucose, glucose would spontaneously form pyruvate. More pyruvate would be formed at the end of glycolysis. High (possibly toxic) levels of glucose would accumulate in the cell. Glucose could move out of the cell, slowing cellular respiration.

Glucose could move out of the cell, slowing cellular respiration.

______________ is found in animals, and possesses a large, central protein. ____________ is found in plants, and lacks a central protein. Glycogen; Glycogen also Starch; Glycogen Glycogen; Starch Starch; Starch also

Glycogen; Starch

You may be familiar with the story of Philippides, the famous Grecian who ran the first marathon and then died after completing his run. Based on what you know of aerobic respiration and fermentation, why might Philippides have died? His muscles may have produced toxic levels of ethanol, causing his blood to become more basic. His muscles may have produced toxic levels of both ethanol and lactic acid, causing his blood to become more acidic. His muscles may have produced toxic levels of ethanol, causing his blood to become more acidic. His muscles may have produced toxic levels of lactic acid, causing his blood to become more basic. His muscles may have produced toxic levels of lactic acid, causing his blood to become more acidic.

His muscles may have produced toxic levels of lactic acid, causing his blood to become more acidic.

Which of the following statements is true regarding the proton gradient? It is synonymous with the "electrochemical gradient." It contains a great deal of kinetic energy. It results from differences in the concentration of hydroxide ions. It results from a combination of "neutral" charges. None of the answer options is correct.

It is synonymous with the "electrochemical gradient."

Which of the following correctly characterizes the F1 subunit of ATP synthase? It is embedded in the inner mitochondrial membrane. It forms the channel through which protons flow. It is the catalytic unit that synthesizes ATP. None of these answer options correctly characterizes the F1 subunit of ATP synthase.

It is the catalytic unit that synthesizes ATP.

Which of the following statements is true regarding a reducing agent? It is never oxidized. It is usually oxygen. It gains electrons. It is an electron acceptor. It loses electrons.

It loses electrons.

Imagine that you notice rust has formed on the frame of your bicycle. How would this have happened? The iron in your bicycle frame was reduced and gained electrons. The iron in your bicycle frame was oxidized and gained electrons. The iron in your bicycle frame was oxidized and lost electrons. The iron in your bicycle frame was reduced and lost electrons.

The iron in your bicycle frame was oxidized and lost electrons.

Which of the following statements is true regarding the equation C6H12O6 + 6O2 →6CO2+ 6H2O + energy? The oxygen atoms in both CO2 and H2O are electronegative, and glucose could be considered a reducing agent. The oxygen atoms in both CO2 and H2O are electronegative. Glucose could be considered a reducing agent. The movement of hydrogen atoms in reactions involving C6H12O6 and H2O yields no information regarding the movement of electrons. In CO2, the oxygen atoms lose electrons and the carbon atom is oxidized

The oxygen atoms in both CO2 and H2O are electronegative, and glucose could be considered a reducing agent.

A researcher is studying a population of bacteria that carry out the citric acid cycle, but do so in reverse. What statements are likely true of these bacteria? These bacteria will release CO2 as a waste product and will carry out cellular respiration within their mitochondria. An individual bacterium will produce most of its energy via the citric acid cycle. The bacteria will release CO2 as a waste product. These bacteria will produce sugars from intermediates of the citric acid cycle. These bacteria carry out cellular respiration in their mitochondria

These bacteria will produce sugars from intermediates of the citric acid cycle.

Which of the following statements is true regarding triacylglycerols? Triacylglycerols are stored in the liver and are used to produce ATP via substrate-level phosphorylation. ATP is derived from triacylglycerols through beta-oxidation and substrate-level phosphorylation. Like glycogen, triacylglycerols are stored primarily in the liver. Triacylglycerols have no structural similarities to glycerol. Triacylglycerols can be used to generate acetyl-CoA.

Triacylglycerols can be used to generate acetyl-CoA.

The pyruvate dehydrogenase complex plays a role in which of the following processes? the formation of NADH the oxidation of pyruvate the formation of acetyl-CoA the formation of CO2 All of the answer options are correct.

all

Which of the following statements are true regarding acetyl-CoA synthesis? This process occurs within the matrix of mitochondria. This process constitutes the second stage of cellular respiration. The process produces both CO2 and acetyl-CoA. The process yields no ATP via substrate-level phosphorylation. All of the answer options are correct.

all

Glycolysis is: aerobic. anaerobic. aerobic in some organisms but anaerobic in others. aerobic in some tissues but anaerobic in others. None of the answer options is correct.

anaerobic.

Lactic acid fermentation occurs in (select all correct answer options): animals and fungi. fungi and bacteria. plants and bacteria. bacteria and animals. animals and plants.

bacteria and animals.

How did the earliest organisms on Earth most likely produce ATP? by the citric acid cycle by acetyl CoA synthesis by oxidative phosphorylation by glycolysis

by glycolysis

Cellular respiration is a series of _____ reactions. carboxylation catabolic phosphorylation anabolic glycolytic

catabolic

The second phase of glycolysis: generates ATP by oxidative phosphorylation. generates ATP by substrate level phosphorylation. cleaves a phosphorylated sugar molecule and rearranges the products. reduces NAD+ to NADH. phosphorylates glucose.

cleaves a phosphorylated sugar molecule and rearranges the products.

A high-energy electron from NADH entering the electron transport chain would travel among components of the chain in what sequence? complex I, coenzyme Q, complex III, cytochrome C, complex IV, oxygen complex I, coenzyme Q, complex II, cytochrome C, complex III, coenzyme Q, complex IV, cytochrome C, oxygen complex I, coenzyme Q, complex III, cytochrome C, ATP synthase, oxygen complex II, cytochrome C, complex IV, cytochrome C, oxygen complex II, coenzyme Q, complex IV, cytochrome C, ATP synthase, oxygen

complex I, coenzyme Q, complex III, cytochrome C, complex IV, oxygen

Phosphorylating glucose during phase 1 of glycolysis: releases phosphorylated glucose from cells. destabilizes the glucose molecule so that it can be broken down in stage 2. provides electrons to reduce NAD+ in stage 3. provides electrons to reduce FADH in stage 3. None of the answer options is correct.

destabilizes the glucose molecule so that it can be broken down in stage 2.

At what phase of glycolysis is NADH formed? during Phase 1, when fructose 1,6-biphosphate is formed during Phase 1, when glucose is phosphorylated during Phase 3, when glyceraldehyde 3-phosphate is phosphorylated during Phase 2, when glyceraldehyde 3-phosphate is formed during Phase 3, when pyruvate is finally formed

during Phase 3, when glyceraldehyde 3-phosphate is phosphorylated

In the first three stages of cellular respiration, the chemical energy in glucose is transferred to: proton pumps and ATP. electron carriers and ATP. only coenzyme Q. ATP and cytochrome b. cytochrome b and coenzyme Q.

electron carriers and ATP.

The proteins of the electron transport chain are: located in the mitochondrial matrix. located in the intermembrane space of mitochondria. embedded in the outer mitochondrial membrane. embedded in both mitochondrial membranes. embedded in the inner mitochondrial membrane.

embedded in the inner mitochondrial membrane.

The first phase of glycolysis requires the input of two ATP molecules. It is therefore: endergonic. exergonic. oxidative. reducing. None of the answer options is correct.

endergonic.

Acetyl-CoA synthesis is remarkably similar to glycolysis in that when one molecule of pyruvate enters into a mitochondrion, two molecules of acetyl-CoA are formed. true false

false

During the action of ATP synthase, the kinetic energy of the proton gradient is transformed into potential energy. true false

false

In a plant cell, all stages of cellular respiration are carried out in the cytoplasm. true false

false

Like glycolysis, acetyl-CoA synthesis produces both pyruvate and acetyl-CoA. These two products feed directly into the citric acid cycle and are the reactants for this process. true false

false

The majority of cells within the human body have a very high baseline amount of ATP, so cells are always prepared for any long-term activity. true false

false

Fermentation takes place: in the mitochondrial matrix. on the outer mitochondrial membrane. on the inner mitochondrial membrane. in the intermembrane space of mitochondria. in the cytoplasm.

in the cytoplasm.

Due to the pumping action of the electron transport chain, protons have a high concentration in the _____ and a low concentration in the _____. mitochondrial matrix; extracellular fluid mitochondrial matrix; cytoplasm mitochondrial matrix; intermembrane space intermembrane space; cytoplasm intermembrane space; mitochondrial matrix

intermembrane space; mitochondrial matrix

Acetyl-CoA synthesis is an important step in cellular respiration because: it generates ATP by substrate level phosphorylation. it is the first step in oxidative phosphorylation. it transfers large numbers of high-energy electrons to electron carriers. it eliminates toxic pyruvate from the cell. it links glycolysis with aerobic respiration.

it links glycolysis with aerobic respiration.

Starting with glycolysis, lactic acid and ethanol fermentation generate only two ATP per glucose molecule. The remaining chemical energy from the glucose is found primarily in: CO2. FADH2. lactic acid and ethanol. NADH. GTP.

lactic acid and ethanol.

During acetyl-CoA synthesis, pyruvate is broken down into CO2 and an acetyl group. The CO2 is: less oxidized than the acetyl group. more reduced than the acetyl group. more energetic than the acetyl group. less energetic than the acetyl group. None of the answer options is correct.

less energetic than the acetyl group.

In glycolysis, ATP is synthesized via: electron carriers. redox reactions. substrate level phosphorylation. both substrate level and oxidative phosphorylation. oxidative phosphorylation.

substrate level phosphorylation.

Which is the only reaction in the citric acid cycle that produces ATP by substrate-level phosphorylation? the formation of oxaloacetate the formation of succinate the formation of fumarate the formation of malate the formation of citrate

the formation of succinate

The chemical bonds of carbohydrates and lipids have high potential energy because: they are easy to hydrolyze. their electrons are far away from the nuclei of the atoms. they are easy to phosphorylate. they are strong oxidizing agents. they are strong reducing agents

their electrons are far away from the nuclei of the atoms.

Recall that the citric acid cycle starts with a four-carbon molecule, but that most of its intermediates are molecules that contain six carbons. How is this possible? through the reaction of citrate and cis-aconitate through the reaction of malate and fumarate through the reaction of acetyl-CoA and oxaloacetate through the reaction of succinate and succinyl-CoA through the reaction of malate and oxaloacetate

through the reaction of acetyl-CoA and oxaloacetate

A beer maker is using yeast to make his favorite brew. How does yeast produce ethanol? directly from the reduction of glucose through the reduction of lactic acid through the oxidation of acetaldehyde, derived from pyruvate through the direct reduction of pyruvate, similar to lactic acid fermentation through the reduction of acetaldehyde, derived from pyruvate

through the reduction of acetaldehyde, derived from pyruvate

Although cellular respiration is typically thought of as an aerobic process, glycolysis itself is actually anaerobic. true false

true

Although glycolysis produces four molecules of ATP via substrate-level phosphorylation, the net gain of ATP for the cell is two molecules. This is due to the fact that glycolysis is—at first—endergonic. true false

true

Imagine that you exhale after a deep breath. What are you not exhaling? waste products of glycolysis CO2 waste products of both acetyl-CoA synthesis and the citric acid cycle waste products of the citric acid cycle waste products of acetyl-CoA synthesis

waste products of glycolysis