SmartBook Assignment Module 4-SB: Chapter 7

Each turn of the citric acid cycle produces Blank______.

3 NADH and 1 FADH2

How many ATP molecules are produced by oxidative phosphorylation for every one molecule of glucose that enters the pathways of cellular respiration?

30-34 ATP

Which term is used to describe an environment that lacks oxygen?

Anaerobic

As a result of the reactions of the citric acid cycle, the carbons from acetyl CoA are released as _____ _____.

Blank 1: carbon or C Blank 2: dioxide or O2

The breakdown of pyruvate results in the production of acetyl-CoA, which then enters the _____ _____ cycle.

Blank 1: citric or tricarboxylic Blank 2: acid

While glycolysis occurs in the _____ in eukaryotic cells, the remaining steps of respiration occur in the _____ of the cell.

Blank 1: cytosol or cytoplasm Blank 2: mitochondria or mitochondrion

This figure shows the process of _____ in muscle cells.

Blank 1: fermentation, lactic acid fermentation, or lactate fermentation

In the second phase of glycolysis, a molecule of _____-1,6-_____ is cleaved into two molecules of _____-3-phosphate.

Blank 1: fructose Blank 2: bisphosphate, biphosphate, or diphosphate Blank 3: glyceraldehyde

The rate of glycolysis is regulated primarily by the availability of substrates such as _____ and by the process of _____ inhibition.

Blank 1: glucose, carbohydrates, or sugars Blank 2: feedback

The citric acid cycle begins when acetyl CoA is combined with _____ to produce _____.

Blank 1: oxaloacetate, oxaloacetic acid, oxaloaceticacid, or oxaloacetic-acid Blank 2: citrate, citric acid, citricacid, or citric-acid

In the final stage of glucose metabolism, the high-energy electrons from NADH and FADH2 are removed and used to produce more ATP. This process is called _____ _____.

Blank 1: oxidative Blank 2: phosphorylation

During the cleavage stage of glycolysis, a molecule with _____ carbon atoms is broken into two molecules of _____-3-phosphate.

Blank 1: six or 6 Blank 2: glyceraldehyde

The removal of a phosphate from 1,3-bisphosphoglycerate allows for the transfer of the phosphate to ADP, producing ATP via _____-_____ phosphorylation.

Blank 1: substrate Blank 2: level

Oxidative phosphorylation is regulated by the availability of _____ for the electron transport chain and by the ratio of _____ to ADP.

Blank 1: substrates, NADH, O2, oxygen, ETC substrates, or electron substrates Blank 2: ATP

The electron transport chain results in the oxidation of what energy intermediates produced in the earlier steps of cellular respiration?

NADH FADH2

Which of the following molecules are energy intermediates produced during cellular respiration?

NADH FADH2 ATP

What energy intermediates are produced in the citric acid cycle?

NADH GTP FADH2

During oxidative phosphorylation, which molecules are oxidized?

NADH and FADH2

Which of the following best describes the chemical reactions of oxidative phosphorylation?

NADH is oxidized and ATP is produced.

One important component of the electron transport chain is cytochrome oxidase. Which of the following inhibits this complex?

Cyanide

When a muscle is working strenuously and becomes anaerobic, pyruvate from glycolysis is reduced to lactate to allow the oxidation of Blank______.

NADH to NAD+

True or false: The redox reactions of the electron transport chain transfer electrons from components with higher electronegativity to those with lower electronegativity.

False

The citric acid cycle is directly regulated by which three of the following?

Feedback inhibition NAD+ levels Acetyl-CoA levels

What type of pathway produces ATP by substrate-level phosphorylation without any net oxidation of organic molecules?

Fermentation

During the energy investment phase of glycolysis, glucose is converted to which molecule?

Fructose-1,6-bisphosphate

During the breakdown of pyruvate, two high-energy electrons are removed from it. These are then used to convert Blank______.

NAD+ to NADH

Under anaerobic conditions, high levels of Blank______ may cause the production of free radicals.

NADH

What is produced during the oxidation of glyceraldehyde-3-phosphate?

NADH

Which two molecules act as feedback inhibitors of the citric acid cycle in mammals?

NADH ATP

What are the products of the breakdown of a single pyruvate molecule?

One CO2 One NADH molecule One acetyl group

What happens during the fermentation reactions that occur in muscle cells?

Pyruvate is reduced to lactate. NADH is oxidized to NAD+.

What is the outcome of aerobic respiration?

O2 is reduced to H2O

The three subunits of the membrane embedded region of ATP synthase are called Blank______.

a, b, and c

The metabolic reactions that a cell uses to get energy from food molecules and release waste products are collectively called Blank______.

cellular respiration

Glucose contains covalent bonds that store a large amount of Blank______.

chemical energy

Energy stored in a proton gradient is used to synthesize ATP from ADP and Pi during the process of _____.

chemiosmosis

The use of energy stored in a proton gradient to drive the synthesis of ATP is called Blank______.

chemiosmosis

The citric acid cycle consists of Blank______ reactions or steps.

eight

A series of redox reactions makes up the _____ transport chain.

electron or e-

In the electron transport chain, electrons are transferred to molecules with increasingly higher Blank______.

electronegativity

The measure of an atom's ability to attract electrons is called its _____.

electronegativity

Electronegativity refers to the ability to attract _____.

electrons or e-

During glycolysis, one molecule of _____ is broken down into two molecules of pyruvate, driving the synthesis of ATP.

glucose

During the first phase of glycolysis, ATP is hydrolyzed so that phosphate groups can be added to Blank______.

glucose

Glycerol can enter into glycolysis after it is converted to Blank______.

glyceraldehyde-3-phosphate

Fats are typically broken down to _____ and fatty acids.

glycerol

ATP is an allosteric inhibitor of phosphofructokinase, so when levels of ATP are high, Blank______ is slowed.

glycolysis

Fats are broken down into glycerol and fatty acids. The glycerol is converted to glyceraldehyde-3-phosphate, which enters Blank______.

glycolysis

In the Warburg effect, cancer cells preferentially use Blank______ for ATP production. This phenomenon is used to clinically diagnose cancer via PET scans.

glycolysis

Organisms that can use only oxygen as a final electron acceptor can generate ATP via _____ during anaerobic conditions.

glycolysis

PET scans can be used to detect regions of the body with high levels of Blank______.

glycolysis

The energy that allows for the phosphorylation of ADP to produce ATP is provided by the flow of _____ ions through ATP synthase.

hydrogen, hydrogens, H+, protons, H, or proton

The process of glycolysis can take place Blank______.

in the presence or absence of oxygen

During glycolysis, fructose-1,6-bisphosphate is split into two three-carbon sugars. The rearrangement of one of these molecules results in the net production of two molecules of Blank______.

glyceraldehyde-3-phosphate

The cristae increase the amount of ATP that can be made by Blank______.

increasing the surface area of the inner mitochondrial membrane

The majority of ATP produced in aerobic cellular respiration is during Blank______.

oxidative phosphorylation

The final electron acceptor in the electron transport chain is Blank______.

oxygen

During aerobic respiration, the final electron acceptor in the electron transport chain is _____.

oxygen, O2, 02, O, or oxygen gas

Many organisms, including animals and yeasts, can only use _____ as a final electron acceptor in their electron transport chains.

oxygen, O2, 0xygen, oxygen gas, or 02

The purpose of the energy investment phase of glycolysis is to Blank______.

prime glucose for the exergonic reactions to follow

The hydrolysis of ATP early in glycolysis leads directly to Blank______.

the phosphorylation of glucose

In glycolysis, what is the net yield of ATP per molecule of glucose?

Two ATP molecules

Glycolysis consists of _____ reactions or steps.

10

For every glucose molecule that enters glycolysis, the energy liberation phase (steps 6-10) generates a total of Blank______.

2 NADH and 4 ATP molecules

The net products of glycolysis are Blank______.

2 pyruvate, 2 NADH, 2 H+, 2 ATP, and 2 H2O

The number of ATP molecules hydrolyzed during the first stage of glycolysis is _____.

2, two, 2 ATP, 2 ATP molecules, 2 ATPs, or a couple

Glycolysis results in a net gain of _____ ATP per glucose molecule.

2, two, a couple of, or a pair of

In the first reaction of the citric acid cycle, oxaloacetate, which contains Blank______ carbons, is combined with acetyl-CoA, which contains Blank______ carbons in its acetyl group, to produce citric acid, which contains Blank______ carbons.

4; 2; 6

Which of the following is the best description of the process of cellular respiration?

A means to extract energy from organic molecules

The GTP produced in the citric acid cycle is used to synthesize Blank______.

ATP

What is the main product of cellular respiration?

ATP

List the products of the citric acid cycle.

ATP Carbon dioxide FADH2 NADH

During oxidative phosphorylation, ATP is produced by which enzyme?

ATP synthase

During oxidative phosphorylation, what enzyme produces ATP?

ATP synthase

During chemiosmosis, the energy in the form of a proton gradient is converted to chemical potential energy in _____ molecules.

ATP, adenosine-triphosphate, adenosine triphosphate, or adenosinetriphosphate

The primary aim of cellular respiration is to produce molecules of _____, which provide energy to the cell.

ATP, adenosinetriphosphate, or adenosine triphosphate

______ involves the complete breakdown of glucose in the presence of oxygen gas to yield carbon dioxide, water, and energy in the form of ATP.

Aerobic respiration

Which of the following molecules are used as energy sources by living organisms?

Amino acids Sugars Fatty acids

What happens during substrate-level phosphorylation?

An enzyme transfers a phosphate group from an organic molecule to ADP

How can the flow of electrons through the electron transport chain be described?

An exergonic process

During strenuous exercise, what type of condition may develop in cells when the rate of oxygen delivery cannot keep up with the rate of oxygen demand?

Anaerobic

Which of the following factors regulate the rate of glycolysis?

Availability of glucose Feedback inhibition

Glycolysis is the pathway for glucose breakdown in which of the following?

Bacteria Archaea Eukaryotes

What field is the study of the chemical processes that occur in living things?

Biochemistry

During the complete oxidation of a glucose molecule during aerobic cellular respiration, glycolysis produces _____ ATP (net), the citric acid cycle produces _____ ATP, and oxidative phosphorylation produces between _____ and _____ ATP.

Blank 1: 2 or two Blank 2: 2 or two Blank 3: 30 or thirty Blank 4: 34, thirty-four, or thirty four

The third stage of glycolysis (steps 6-10) is called the energy liberation phase. It produces a total of _____ molecule(s) of NADH and _____ molecule(s) of ATP for every molecule of glucose that enters the pathway. Note: This question is NOT asking about the net yield but the total.

Blank 1: 2 or two Blank 2: 4 or four

Chemiosmosis can produce between _____ and _____ ATP molecules for every molecule of glucose that is oxidized.

Blank 1: 30 or thirty Blank 2: 34 or thirty-four

Formation of ATP within the electron transport chain is catalyzed by the enzyme _____ _____.

Blank 1: ATP Blank 2: synthase or synthetase

The three energy intermediates produced during cellular respiration are _____, _____, and _____.

Blank 1: ATP or GTP Blank 2: NADH Blank 3: FADH2 or FADH

The component of the ETC that receives electrons from NADH is _____ dehydrogenase, while _____ reductase receives electrons from FADH2.

Blank 1: NADH Blank 2: succinate

A single run of the citric acid cycle results in the production of two molecules of carbon dioxide, one molecule of ATP (or GTP), three molecules of _____, and one molecule of _____, from one acetyl group.

Blank 1: NADH or 3 NADH Blank 2: FADH2 or 1 FADH2

The principal energy-yielding pathway that involves the breakdown of glucose in the presence of oxygen is called _____ _____.

Blank 1: aerobic or cellular Blank 2: respiration

What is the first phase of glycolysis termed?

Energy investment

Yeast cells can metabolize sugar under anaerobic conditions by breaking down pyruvate. Which of these are the end products of fermentation in yeast?

Ethanol CO2 NAD+

Which of these organic molecules can be produced during fermentation reactions?

Ethanol Lactate

What reactants are required for the citric acid cycle?

FAD NAD+ GDP2- Acetyl-CoA

What molecules become oxidized during oxidative phosphorylation?

FADH2 NADH

True or false: Amino acids can be used for cellular respiration only after they are converted to glucose.

False

True or false: Glycolysis can only occur under aerobic conditions.

False

True or false: NADH and FADH2 donate electrons to the electron transport chain at the same point.

False

True or false: The flow of electrons through the electron transport chain requires an input of energy.

False

True or false: The matrix of the mitochondrion generally has a more positive charge than the intermembrane space.

False

True or false: The process of glycolysis takes place in the mitochondria.

False

What are the products of the citric acid cycle? Select all that apply.

GTP FADH2 CO2 CoA—SH NADH

During the cleavage phase of glycolysis, fructose-1,6-bisphosphate is split into two different three-carbon molecules. Which ones?

Glyceraldehyde-3-phosphate Dihydroxyacetone phosphate

What problem results from the buildup of NADH and decrease of NAD+ under anaerobic conditions?

High concentrations of NADH can lead to the release of free radicals, which can damage DNA and proteins.

Which of the following statements about invaginations of the inner mitochondrial membrane are true?

Increase surface area Allow for greater ATP production Are called cristae

What happens to the acetyl-CoA that is produced from pyruvate?

It enters the citric acid cycle.

When pyruvate is broken down, the acetyl group is attached to coenzyme A, and two high-energy electrons are transferred to _____.

NAD+ or NAD

The citric acid cycle is considered cyclical because Blank______.What happens to the GTP that is produced in the citric acid cycle?

It is used to make ATP.

What happens to the GTP that is produced in the citric acid cycle?

It is used to make ATP.

What molecule is produced during fermentation in muscle cells?

Lactate

Where does the citric acid cycle occur in eukaryotic cells?

Mitochondrial matrix

In order for glycolysis to continue in the absence of cellular respiration with oxygen, which product must be regenerated?

NAD+

Under anaerobic conditions, glycolysis slows due to the depletion of Blank______.

NAD+

What intermediate is regenerated as a result of the reactions of the citric acid cycle?

Oxaloacetate

What four pathways are involved in the breakdown of glucose to carbon dioxide and water?

Oxidative phosphorylation Breakdown of pyruvate Citric acid cycle Glycolysis

What is the main function of oxidative phosphorylation?

Production of ATP

Select the organic molecules obtained from food that are most typically used as energy sources.

Proteins Carbohydrates Fats

Which of the following are end products of glycolysis?

Pyruvate ATP NADH

During cellular respiration, acetyl-CoA is formed during a reaction that also does what?

Removes a CO2 from pyruvate

The structural components of the electron transport chain include which of the following?

Small organic molecules Protein complexes

Which of the following are reasons that the maximum amount of ATP may not always be produced through oxidative phosphorylation?

Some NADH might be used to synthesize organic molecules. Some FADH2 might be used for anabolic pathways. The mitochondrion may use some of the H+ gradient for other purposes.

What type of motion is coupled to the synthesis of ATP by the enzyme ATP synthase?

Spinning

What process is used to synthesize ATP during glycolysis?

Substrate-level phosphorylation

The yield of ATP per molecule of glucose is often lower than the maximum possible value. Why is this so?

The H+ gradient is also used to transport pyruvate into the matrix. Some of the NADH and FADH2 are used in other biochemical pathways.

Which of the following factors regulate oxidative phosphorylation?

The availability of NADH The availability of O2 The ATP/ADP ratio

Amino acids can be broken down or modified so that they can enter which pathways?

The citric acid cycle Glycolysis

In eukaryotic cells, which of the following metabolic pathways occur in the mitochondria?

The citric acid cycle The breakdown of pyruvate Oxidative phosphorylation

What is the source of energy for the synthesis of ATP by the enzyme ATP synthase?

The flow of protons down their electrochemical gradient

Why does fermentation produce less ATP than aerobic respiration?

The pyruvate produced during glycolysis is not oxidized to produce additional ATP. Electrons in the NADH produced during glycolysis are not used to make ATP by chemiosmosis.

The second event in oxidative phosphorylation is the production of ATP by the enzyme ATP _____.

The second event in oxidative phosphorylation is the production of ATP by the enzyme ATP .

What evidence suggests that glycolysis arose very early in the evolution of life?

The steps of glycolysis are found in bacteria and archaea as well as eukaryotes.

Why are phosphate groups added to glucose during the first phase of glycolysis?

To raise its free energy so that later reactions can be exergonic

True or false: PET scans detect areas with abnormally high levels of glycolysis.

True

True or false: Some organisms can only use oxygen as a final electron acceptor.

True

The preferential use of glycolysis for ATP production in cancer cells is called the Blank______.

Warburg effect

If an organism can use only O2 as a final electron acceptor, can it generate ATP under anaerobic conditions?

Yes, it can generate ATP through glycolysis.

Ethanol production by yeast results when NADH donates its electrons to Blank______.

acetaldehyde

When a carbon dioxide is removed from pyruvate, the product is a(n) _____ group, which then attaches to coenzyme A.

acetyl, C2H3O, or COCH3

The pyruvate molecule produced in glycolysis undergoes a reaction which results in the production of one _____ group and one CO2 molecule.

acetyl, acetyl CoA, or acetyl-CoA

The breakdown of fatty acids results in the production of Blank______.

acetyl-CoA

At high concentrations, ATP regulates the rate of glycolysis through Blank______.

allosteric inhibition of phosphofructokinase

An environment where oxygen is absent is termed _____.

anaerobic or anoxic

Consider a scenario where the rate of oxygen delivery to cells cannot keep up with the rate of oxygen demand. This would lead to conditions that are known as _____.

anaerobic or anoxic

The study of the chemistry of living organisms is called _____.

biochemistry

Which type of ATP synthase subunit forms a ring in the membrane?

c

In yeast cells, fermentation regenerates NAD+ and produces which chemicals?

carbon dioxide and ethanol

The second phase of glycolysis is also called the Blank______ phase

cleavage

During chemiosmosis, energy stored in a proton gradient is Blank______.

converted to chemical bond energy in ATP

The Blank______ bonds in glucose store large amounts of energy.

covalent

Because the citric acid cycle regenerates one of the molecules that is necessary to start the reactions, it is considered Blank______.

cyclical

At the end of the electron transport chain, Blank______ catalyzes the transfer of electrons to O2.

cytochrome oxidase

Glycolysis occurs in the Blank______.

cytosol

What are the products of fat digestion?

fatty acids and glycerol

The breakdown of glucose to lactate or ethanol as a final end product is an example of _____.

fermentation

Cyanide is lethal to cells because it Blank______.

inhibits the flow of electrons along the ETC

In eukaryotic cells, the electron transport chain is located in the Blank______.

inner mitochondrial membrane

The oxidation of NADH initially leads to a high concentration of protons in the Blank______.

intermembrane space

The oxidation of NADH in the mitochondrion leads to an electrochemical gradient where there are more protons in the _____ space than there are in the matrix.

intermembrane, inter membrane, inner, or inner membrane

During the first phase of glycolysis, there is a(n) Blank______.

investment of ATP

The citric acid cycle is considered cyclical because Blank______.

it regenerates a required substrate

In eukaryotes, the three metabolic pathways of pyruvate breakdown, the citric acid cycle, and oxidative phosphorylation all occur in the _____.

mitochondria or mitochondrion

Due to the electron transport chain, the proton concentration is the lowest in the Blank______.

mitochondrial matrix

In eukaryotic cells, the citric acid cycle occurs in the _____ matrix.

mitochondrial, mitochondria, or mitochondrion

In order for cellular respiration to continue, the pyruvate produced in glycolysis must be transported into the Blank______.

mitochondrion

In the final reaction of the citric acid cycle, malate is oxidized to produce Blank______. The cycle can then re-start.

oxaloacetate

As electrons travel through the electron transport chain, _____ ions are pumped across the cristae into the space between the inner and outer mitochondrial membranes, from a low concentration to a high concentration.

protons, H+, hydrogen, H, or proton

The energy released during the transfer of electrons in the electron transport chain is used to Blank______.

pump protons across the inner mitochondrial membrane

The electron transport chain involves a series of Blank______ reactions.

redox

The final step in fermentation, leading to the production of lactate or ethanol, results from pyruvate or acetaldehyde being _____ by NADH.

reduced

Muscle cells overcome the buildup of NADH and decrease of NAD+ under anaerobic conditions by Blank______.

reducing pyruvate to lactate

ATP synthase functions like a Blank______.

rotary machine

The ATP produced during glycolysis is the result of _____-level phosphorylation.

substrate

How is ATP produced during fermentation?

substrate-level phosphorylation

The transfer of a high energy phosphate group from a phosphorylated organic molecule to ADP is referred to as Blank______.

substrate-level phosphorylation

Fermentation produces less ATP than aerobic respiration because during fermentation Blank______.

the NADH that is made during glycolysis is not used to make ATP by chemiosmosis

Fatty acids can be broken down to acetyl groups, which bind to CoA and enter Blank______.

the citric acid cycle

During oxidative phosphorylation, ATP synthesis is coupled to Blank______.

the removal of high-energy electrons from NADH and FADH2

All the reactions of glycolysis can be grouped into Blank______ phases.

three

Glycolysis involves the breakdown of one molecule of glucose into Blank______.

two molecules of pyruvate

Glycolysis is the breakdown of glucose into Blank______.

two pyruvate molecules

The second stage of glycolysis is called the cleavage phase. Its reactions break a six-carbon molecule into Blank______.

two three-carbon molecules

Electrons from FADH2 are transferred to succinate reductase and then to a small organic molecule called _____.

ubiquinone, coenzymeQ, or oxygen

When electrons are transferred to oxygen in the final step of the electron transport chain, a molecule of _____ is produced.

water, H2O, or H20

The type of fermentation illustrated here occurs in Blank______.

yeast cells

The flow of protons through ATP synthase causes the Blank______ subunit to turn clockwise. This causes the three Blank______ subunits to change their conformations in a way that favors ATP synthesis and release.

γ ; β