BIO 101: Chapter/Lab 7

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Which of the following is the overall balanced equation for alcoholic fermentation? C6H12O6 → 2 C3H6O3 + 2 ATP C6H12O6 → 2 CO2 + 2 C2H5OH + 2 ATP C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + 30-32 ATP

C6H12O6 → 2 CO2 + 2 C2H5OH + 2 ATP

which form of NAD+ has more energy?

NADH

cellular respiration final electron acceptors

O2

ATP synthase is present in mitochondria as well as chloroplast.

T

fermentation

uses substrate-level phosphorylation instead of an ETC to generate ATP

Fermentation produces _ ATP per glucose molecule

2

During photosynthesis Photosystem I functions before Photosystem II.

F

Pyruvic acid starts off the Kreb's Cycle.

F it's Acetyl CoA

In the absence of oxygen, cells need a way to regenerate which compound following glycolysis? Lactate NAD+ Ethanol Glucose Carbon dioxide

NAD+

_________ is the compound that functions as the electron acceptor in glycolysis.

NAD+

what is the oxidized form of NAD+?

NAD+

fermentation final electron acceptors

an organic molecule (such as pyruvate or acetaldehyde)

The ATP made during fermentation is generated by which of the following?

substrate-level phosphorylation

The ATP made during glycolysis is generated by

substrate-level phosphorylation

When an enzyme transfers a phosphate molecule from a metabolic intermediate to ADP, forming an ATP molecule, the process is called

substrate-level phosphorylation

In fermentation of sugars by yeast, what are the products? C6H12O6 + 2 CO2 C6H12O6 2 CO2 + 2 ATP 2 CO2 + 2 C2H5OH + 2 ATP

2 CO2 + 2 C2H5OH + 2 ATP

how many net ATP are produced in glycolysis

2 total

Approximately how many molecules of ATP are produced from the complete oxidation of two molecules of glucose (C6H12O6) in aerobic cellular respiration?

30-32

Cellular respiration produces __ ATP per glucose molecule

32

What color does bromothymol blue change into when in acidic pH conditions? Blue/ green to green Blue/ green to pink Blue/ green to yellow

Blue/ green to yellow

Photosystem I gets its electrons from CO2. ATP. H2O. sun photsystem II

D

Which is a common step in both cellular respiration and fermentation? Glycolysis Kreb's cycle Citric acid cycle Oxidative phosphorylation

Glycolysis

In addition to ATP, what are the end products of glycolysis?

NADH and pyruvate

Glucose has energy in its _______ bonds

covalent

which enzyme releases chemical energy stored in organic molecules by removing hydrogen atoms?

dehydrogenase

What was the color of the bromothymol blue solution after you blew bubbles into the test tube? Blue/ green pink yellow

yellow

Where are the proteins of the electron transport chain located?

mitochondrial inner membrane (not intermembrane space.)

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? About 32 ATP About 16 ATP Two Three Four

4

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

A

Why are (most) plants green? Chlorophyll a reflects green light. Chlorophyll a absorbs green light. Chlorophyll b primarily uses green light as the source of energy for photosynthesis. Green helps plants blend into their environment as a sort of camouflage.

A

the absence of oxygen, cells may continue making ATP using ____. fermentation and anaerobic respiration aerobic respiration the Calvin cycle and aerobic respiration pyruvate oxidation

A

Glycolysis occurs in plant cells only animal cells only. none of the bacterial cells. in cells of every living organism / in all kinds of cells.

in cells of every living organism / in all kinds of cells.

Where do the reactions of glycolysis occur in a eukaryotic cell? In the cytosol In the inner membrane of the mitochondrion In the matrix of the mitochondrion In the intermembrane space of the mitochondrion Across the inner membrane of the mitochondrion

in the cytosol

Where is ATP synthase located in the mitochondrion?

inner membrane

The electron transport chain involved in cellular respiration is located in/on the __________. intermembrane space of the mitochondrion matrix of the mitochondrion inner membrane of the mitochondrion cytosol

inner membrane of the mitochondrion

the energy released from the falling electrons in the ETC are used for pushing the H+ from the inner mitochondrial matrix into the _____ _______ _____ to form a potential gradient with a proton motive force

inner membrane space

lactate

ionized form of lactic acid

In photosynthesis, the chemiosmotic production of ATP requires oxygen. is analogous / similar to the production of ATP in mitochondria. is done by the Calvin cycle. requires the input of NADPH.

is analogous / similar to the production of ATP in mitochondria.

In muscle cells, fermentation produces _____.

lactate and NAD+

The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction:

loses electrons and loses potential energy

Oxidation is defined as the ___________________ of electrons.

loss

Comparing Fermentation with Anaerobic and Aerobic Respiration

-All use glycolysis (net ATP 2) to oxidize glucose and harvest chemical energy of food -All three produce some ATP by substrate-level phosphorylation -In all three, NAD is the oxidizing agent that accepts electrons during glycolysis

Explain how the redox reactions of catabolic pathways yield energy by oxidizing organic fuels.

-the transfer of electrons during chemical reactions -not all redox reactions involve complete transfer of electrons, some share

Which of the following is a product of the light reactions? ATP sugar water carbon dioxide

ATP

Suppose that a cell's demand for ATP suddenly exceeds its supply of ATP from cellular respiration. Which statement correctly describes how this increased demand would lead to an increased rate of ATP production? ATP levels would fall at first, decreasing the inhibition of PFK and increasing the rate of ATP production. ATP levels would fall at first, increasing the inhibition of PFK and increasing the rate of ATP production. ATP levels would rise at first, increasing the inhibition of PFK and increasing the rate of ATP production. ATP levels would rise at first, decreasing the inhibition of PFK and increasing the rate of ATP production.

ATP levels would fall at first, decreasing the inhibition of PFK and increasing the rate of ATP production.

In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of

ATP, CO2, and ethanol (ethyl alcohol).

In which organelles does photosynthesis and cellular respiration take place?

Chloroplast and mitochondrion

Each of the four stages of cellular respiration occurs in a specific location inside or outside the mitochondria. These locations permit precise regulation and partitioning of cellular resources to optimize the utilization of cellular energy. Match each stage of cellular respiration with the cellular location in which it occurs. Labels may be used once, more than once, or not at all.

Glycolysis: cytosol Acetyl CoA Formation: mitochondrial matrix Citric Acid Cycle: mitochondrial matrix Oxidative Phosphorylation: inner mitochondrial membrane

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

H+ concentration across the membrane holding ATP synthase

Why did you use Bromo-Thymol Blue to test for respiration? Hint: search on Internet what is Bromothymol blue It is a biological indicator that detects for the presence of CO2 It is a pH indicator and indicates formation of carbonic acid It helps the peas carry out cellular respiration

It is a pH indicator and indicates formation of carbonic acid

In the oxidation of pyruvate to acetyl CoA, one carbon atom is released as CO2. However, the oxidation of the remaining two carbon atoms—in acetate—to CO2 requires a complex, eight-step pathway—the citric acid cycle. Consider four possible explanations for why the last two carbons in acetate are converted to CO2 in a complex cyclic pathway rather than through a simple, linear reaction. Use your knowledge of the first three stages of cellular respiration to determine which explanation is correct. More ATP is produced per CO2 released in cyclic processes than in linear processes. It is easier to remove electrons and produce CO2 from compounds with three or more carbon atoms than from a two-carbon compound such as acetyl CoA. Redox reactions that simultaneously produce CO2 and NADH occur only in cyclic processes. Cyclic processes, such as the citric acid cycle, require a different mechanism of ATP synthesis than linear processes, such as glycolysis.

It is easier to remove electrons and produce CO2 from compounds with three or more carbon atoms than from a two-carbon compound such as acetyl CoA.

Molecular oxygen (O2) has what role in aerobic cellular respiration? It is necessary in the regeneration of citric acid in the citric acid cycle. It oxidizes pyruvate at the end of glycolysis. It is the final electron acceptor at the end of the electron transport chain. It removes a carbon only from pyruvate, producing CO2. It is the source of oxygen in all of the CO2 molecules produced during cellular respiration.

It is the final electron acceptor at the end of the electron transport chain.

Which of the following statements describes NAD+?

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

The reduced form of the electron acceptor in glycolysis is _________.

NADH

The final recipient of the electron passed along the electron transport chain during aerobic cellular respiration_______. O2 H2O H+ Alcohol

O2

Most of the ATP produced in aerobic cellular respiration comes from which of the following processes? Substrate-level phosphorylation Oxidative phosphorylation Reduction of NAD+ The citric acid cycle Glycolysis

Oxidative phosphorylation

What is the terminal electron acceptor in aerobic cellular respiration? Pyruvate NAD+ Oxygen Glucose

Oxygen

Cellular respiration generates Carbon dioxide T/F

T

Fermentation is not dependent on oxygen T/F

T

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? About 38 ATP Two ATP, six NADH, two FADH2 One ATP, three NADH, one FADH2 Four ATP, six NADH, two FADH2 Three ATP, three NADH, one FADH2

Two ATP, six NADH, two FADH2

What is the difference between aerobic and anaerobic metabolic pathways for producing ATP? aerobic processes require oxygen while anaerobic processes do not require oxygen. aerobic processes do not require oxygen while anaerobic processes do require oxygen. anaerobic processes only occur in eukaryotes while anaerobic processes only occur in prokaryotes.

aerobic processes require oxygen while anaerobic processes do not require oxygen.

fermentation does not use oxygen as the final electron acceptor. the process that releases CO2 is __________ __________ and the process that does not release CO2 is ________ _____ ____________

alcoholic fermentation lactic acid fermentation

In cellular respiration, the energy for most ATP synthesis is supplied by

a proton gradient across a membrane

The oxygen consumed during cellular respiration is involved directly in which process or event?

accepting electrons at the end of the electron transport chain

prior to entering the citric acid cycle, pyruvate is converted to:

acetyle molecule and CO2 ??????

The primary role of oxygen in cellular respiration is to

act as an acceptor for electrons and hydrogen, forming water.

In photosynthesis, ATP and NADPH play role as reactants that fuel Glucose synthesis in the Calvin cycle as its products whose production is associated with events taking place on the inner mitochondrial membrane.

as reactants that fuel Glucose synthesis

What was the initial color of the bromothymol blue solution? Initial= when you placed a few drops of Bromothymol Blue in the test tube containing tap water. Blue/ green pink yellow

blue/green

What is the term for metabolic pathways that release stored energy by breaking down complex molecules? thermodynamic pathways anabolic pathways bioenergetic pathways catabolic pathways fermentation pathways

catabolic pathways

Inside an active mitochondrion, most electrons follow which pathway?

citric acid cycle → NADH → electron transport chain oxygen

Location of Glycolysis is __________ while location of Electron Transport Chain is only _________.

cytoplasm mitochondrial and chloroplast membranes

Where does glycolysis take place in eukaryotic cells?

cytosol

glycolysis occurs in the

cytosol

During redox reactions the loss of electrons from one substance is called reduction. a substance that gains electrons is said to be oxidized. electrons are lost from one substance and added to another substance. protons from one molecule replace the electrons lost from another molecule.

electrons are lost from one substance and added to another substance.

In chemiosmosis, what is the most direct source of energy that is used to convert ADP + i to ATP?

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

The Calvin cycle involves all of the following except: carbon fixation. addition of electrons and protons to carbon. regeneration of NADP+. formation of waste products in the form of CO2.

formation of waste products in the form of CO2.

Of the following molecules in the glycolytic pathway (the process of glycolysis), the one with the most chemical energy is __________. fructose-1,6-bisphosphate fructose-6-phosphate pyruvate glucose glyceraldehyde-3-phosphate

fructose-1,6-bisphosphate

Reduction is defined as the ___________________ of electrons.

gain

Select all the typical products of Fermentation process gas acid alcohol alkali

gas acid alcohol

In glycolysis, the carbon-containing compound that functions as the electron donor is _________.

glucose

which coenzyme helps dehydrogenase?

nicotinamide adenine dinucleotide (NAD+)

Does glycolysis require oxygen?

no, it's anaerobic

ATP is a protein lipid carbohydrate nucleic acid

nucleic acid

Carbon dioxide (CO2) is released during which of the following stages of cellular respiration?

oxidation of pyruvate to acetyl CoA and the citric acid cycle

When a compound donates (loses) electrons, that compound becomes ________. Such a compound is often referred to as an electron donor.

oxidized

What is proton-motive force?

the force provided by a transmembrane hydrogen ion gradient

In mitochondrial electron transport, what is the direct role of O2? to provide the driving force for the synthesis of ATP from ADP and Pi to function as the final electron acceptor in the electron transport chain to provide the driving force for the production of a proton gradient to oxidize NADH and FADH2 from glycolysis, acetyl CoA formation, and the citric acid cycle

to function as the final electron acceptor in the electron transport chain

what is the goal of glycolysis?

to make pyruvate and NADH

In glycolysis, for each molecule of glucose oxidized to pyruvate

two molecules of ATP are used and four molecules of ATP are produced. (net total of 2 ATP)

chemiosmosis

use of energy in a H+ gradient to drive cellular work

anaerobic respiration

uses ETC with final electron acceptor other than oxygen ex: sulfate

Which of the two, produces maximum ATP? Aerobic respiration Fermentation

Aerobic respiration

When you blew air in the test tube through straw: What caused the solution with Bromothymol Blue to change color? As you blew into the test tube, oxygen dissolved into the water and formed ox and acid. This lowered the pH of the solution. As you blew the test tube, CO2 dissolved in the water and formed carbonic acid. This lowered the pH of the solution. As you blew into the test tube, and CO2 was driven off from the solution. Since the tube was removed from the water, the solution became less acidic and the pH was raised.

As you blew the test tube, CO2 dissolved in the water and formed carbonic acid. This lowered the pH of the solution.

In fermentation of sugars by yeast, what are the reactants? C6H12O6 + 2 CO2 C6H12O6 2 CO2 + 2 ATP 2 CO2 + 2 C2H5OH + 2 ATP

C6H12O6

Write down the overall balanced equation for cellular respiration. Which gets oxidized and which gets reduce? Which molecule is the reducing agent and which is the oxidizing agent?

C6H12O6 + 6O2 -> 6CO2 + 6H2O + Energy (ATP+heat) -C6H12O6 gets oxidized to 6CO2 -6O2 gets reduced to 6H2O

Which of the following is the overall balanced equation for alcoholic fermentation? C6H12O6 → 2 C3H6O3 + 2 ATP C6H12O6 → 2 CO2 + 2 C2H5OH + 2 ATP C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + 34 - 38 ATP

C6H12O6 → 2 CO2 + 2 C2H5OH + 2 ATP

The ATP that is generated in glycolysis is produced by substrate-level phosphorylation, a very different mechanism than the one used to produce ATP during oxidative phosphorylation. Phosphorylation reactions involve the addition of a phosphate group to another molecule. Sort the statements into the appropriate bin depending on whether or not they correctly describe some aspect of substrate-level phosphorylation in glycolysis.

Correct Statements: -one of the substrates is a molecule derived from the breakdown of glucose -A bond must be broken between an organic molecule and phosphate before ATP can form -An enzyme is required in order for the reaction to occur Incorrect statements: -The phosphate group added to ADP to make ATP comes from free inorganic phosphate ions -The enzymes involved in ATP synthesis must be attached to a membrane to produce ATP.

The light reactions occur in the __________ while the Calvin cycle occurs in the __________. stroma . . . thylakoid membranes stroma . . . nucleus cytoplasm . . . stroma cytoplasm . . . thylakoid membrane thylakoid membranes . . . stroma

D

Which of the following is correctly matched? oxidation: gain of neutrons reduction: loss of potential energy oxidation: increase of hydrogen atoms reduction: gain of electrons

D

first stage of cellular respiration

Glycolysis: glucose is broken down into pyruvic acid + NADH + 4 ATP (net gain of 2 ATP)

Electron Transport Chain

Location: Cristae Input: FADH2 and NADH, Oxygen Output: Water

Glucose enters into glycolysis and some of its energy (in the form of electrons) is placed on the electron carrier ___________. The glucose has been converted to __________________. This molecule travels to the __________ of the mitochondria

NAD+ pyruvate matrix

the electrons in glucose are initially placed onto an electron carrier called _____________________.

NAD+ to yield NADH

When a poison such as cyanide blocks the electron transport chain, glycolysis and the citric acid cycle also eventually stop working. Which of the following is the best explanation for this? The uptake of oxygen stops because electron transport was inhibited. They run out of ADP. Electrons are no longer available from the electron transport chain to power glycolysis and the citric acid cycle. NAD+ and FAD are not available for glycolysis and the citric acid cycle to continue. A high level of NADH is present in the cell.

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

Which of the following statements describes NAD+? NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle NAD+ has more chemical energy than NADH NAD+ can donate electrons for use in oxidative phosphorylation In the absence of NAD+, glycolysis can still function

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

what is the reduced form of NAD+ and what is it carrying?

NADH carrying 2e' and 1 H+

Which process is the one in which glucose is oxidized to generate two molecules of pyruvate and in which ATP and NADH are produced? Fermentation Chemiosmosis The citric acid cycle None of the listed responses is correct. The oxidation of pyruvate

None of the listed responses is correct.

Glycolysis is not dependent on oxygen T/F

T

UV light has shorter wavelength than visible light.

T

During Glycolysis, total 4 ATPs are synthesized.

T only 2 NET ATP are produced, but 2 are used and hence net gain is 2 ATPs.

What process occurs within Box B?

The citric acid cycle transfers electrons to NADH and FADH2.

What is the main advantage of the C4 and CAM photosynthesis strategies over the C3 strategy? They help the plant conserve water and synthesize glucose efficiently under hot, dry conditions. They allow the plant to fix carbon more efficiently under conditions of low atmospheric CO2. They allow the plant to fix carbon more efficiently in cold conditions. They allow the plant to avoid photorespiration by producing a five-carbon sugar in place of glucose.

They help the plant conserve water and synthesize glucose efficiently under hot, dry conditions.

Lactic acid fermentation

by some fungi and bacteria is used to make cheese and yogurt or by human muscle cells to generate ATP when O2 is scarce, Yeasts and bacteria responsible for producing chocolate from cacao beans also use this process -pyruvate is converted directly to lactate (an ionized form of lactic acid) without producing CO2 •NADH is oxidized regenerating NAD+

Alcohol fermentation

by yeast is used in brewing, winemaking, and baking -pyruvate is converted to ethanol (ethyl alcohol) in two steps 1.CO2 is released from pyruvate, forming acetaldehyde 2.Acetaldehyde is reduced by NADH to ethanol 3.NADH is oxidized regenerating NAD +

Match the following cellular locations with the chemical reactions Glycolysis Citric acid cycle Oxidative phosphorylation Fermentation cell cytoplasm Cytoplasm of a yeast cell Mitochondrial matrix Mitochondrial inner membrane or Cristae

cell cytoplasm Mitochondrial matrix Mitochondrial inner membrane or Cristae Cytoplasm of a yeast cell

Match the material (sugar) with the type of carbohydrate that it is (mono or disaccharide). Answers may be used more than once. maltose sucrose glucose lactose

disaccharide disaccharide monosaccharide disaccharide

Review your answers to the previous questions and continue to dig a little deeper into this topic. Of the sugars that yeast are capable of metabolizing, which ONE do they most prefer? In other words, on which carbohydrate source will the yeast grow the fastest and make the most fermentative products? Glucose Sucrose Lactose Maltose

glucose

Which of the following carbohydrates do yeast metabolize? Glucose Sucrose Lactose Maltose

glucose sucrose maltose

Which of the following carbohydrates do yeast metabolize? Select all that apply. Glucose Sucrose Lactose Maltose

glucose sucrose maltose

Of the sugars that yeast are capable of metabolizing, which do they prefer the most? In other words, on which carbohydrate source will the yeast is likely to grow the fastest and make the most fermentative products? Glucose Sucrose Lactose Maltose

glucose sucrose

Which of the following normally occurs regardless of whether or not oxygen (O2) is present?

glycolysis

Which process in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent?

glycolysis

What process occurs in Box A?

glycolysis glycolysis occurs in the cytosol

Which of the following occur(s) in the cytosol of a eukaryotic cell?

glycolysis and fermentation

During which of the following phases of cellular respiration does substrate-level phosphorylation take place? glycolysis the citric acid cycle oxidation of pyruvic acid glycolysis and the citric acid cycle

glycolysis and the citric acid cycle

Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic cells?

mitochondrial intermembrane space (not inner membrane.)

What molecule is indicated by the letter D?

oxygen Oxygen is the final electron acceptor of cellular respiration

Photoautotrophs: make sugar by eating organic raw materials for their source of energy and their source of carbon. produce sugar molecules by using sunlight for energy and CO2 as a carbon source.. eat other organisms that use light energy to make food molecules. include only the green plants.

produce sugar molecules by using sunlight for energy and CO2 as a carbon source..

Once the electron donor in glycolysis gives up its electrons, it is oxidized to a compound called _________.

pyruvate

In fermentation _____ is reduced and _____ is oxidized.

pyruvate and NADH

Among the products of glycolysis, which compounds contain energy that can be used by other biological reactions? ATP only CO2 only O2 only ATP and NADH only pyruvate, ATP, and NADH pyruvate and ATP only NADH only

pyruvate, ATP, and NADH

what are the final outputs of glycolysis?

pyruvate, NADH, ATP (2)

2 by-products of this pyruvate processing are _________ and _________

pyruvate, NADH, and ATP?????

When a compound accepts (gains) electrons, that compound becomes ________. Such a compound is often referred to as an electron acceptor.

reduced

When a molecule of NAD+ (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a proton), the molecule becomes

reduced

Molecules that are (reduced or oxidized) have more energy?

reduced electrons have more energy when associated with less electronegative atoms like C or H

When the protein gramicidin is integrated into a membrane, an H+ channel forms and the membrane becomes very permeable to protons (H+ ions). If gramicidin is added to an actively respiring muscle cell, how would it affect the rates of electron transport, proton pumping, and ATP synthesis in oxidative phosphorylation? (Assume that gramicidin does not affect the production of NADH and FADH2 during the early stages of cellular respiration.) Sort the labels into the correct bin according to the effect that gramicidin would have on each process.

remains the same: proton pumping rate, electron transport rate, rate of oxygen uptake. decreases or goes to zero: rate of ATP synthesis, size of protein gradient

If muscle cells in the human body consume O2 faster than it can be supplied, which of the following is likely to result? The muscle cells will have trouble making enough ATP to meet demands and the cells will not be able to carry out oxidative phosphorylation. All of the listed events will occur. The cells will not be able to carry out oxidative phosphorylation. The muscle cells will have trouble making enough ATP to meet demands. The cells will consume glucose at an increased rate.

All of the listed events will occur.

Which of the following substances is/are involved in oxidative phosphorylation? All of the listed substances are involved in oxidative phosphorylation. ADP ATP Oxygen None of the listed substance is involved in oxidative phosphorylation.

All of the listed substances are involved in oxidative phosphorylation.

In the experiment of Yeast Fermentation using different sugars; you will present your data using a graph. What kind of graph will you draw?

Bar graph with different kinds of sugars on X axis and height of bubble column on Y axis

How would anaerobic conditions (when no O2 is present) affect the rate of electron transport and ATP production during oxidative phosphorylation? (Note that you should not consider the effect on ATP synthesis in glycolysis or the citric acid cycle.) Neither electron transport nor ATP synthesis would be affected. Electron transport would stop but ATP synthesis would be unaffected. Both electron transport and ATP synthesis would stop. Electron transport would be unaffected but ATP synthesis would stop.

Both electron transport and ATP synthesis would stop.

Under anaerobic conditions (a lack of oxygen), the conversion of pyruvate to acetyl CoA stops. Which of these statements is the correct explanation for this observation? A. Oxygen is required to convert glucose to pyruvate in glycolysis. Without oxygen, no pyruvate can be made. B. In the absence of oxygen, electron transport stops. NADH is no longer converted to NAD+, which is needed for the first three stages of cellular respiration. C. ATP is needed to convert pyruvate to acetyl CoA. Without oxygen, no ATP can be made in oxidative phosphorylation. D. Oxygen is an input to acetyl CoA formation.

C

NADH and FADH2 are both electron carriers that donate their electrons to the electron transport chain. The electrons ultimately reduce O2 to water in the final step of electron transport. However, the amount of ATP made by electrons from an NADH molecule is greater than the amount made by electrons from an FADH2 molecule. Which statement best explains why more ATP is made per molecule of NADH than per molecule of FADH2? The H+ gradient made from electron transport using NADH is located in a different part of the mitochondrion than the H+ gradient made using FADH2. There is more NADH than FADH2 made for every glucose that enters cellular respiration. It takes more energy to make ATP from ADP and Pi using FADH2 than using NADH. Fewer protons are pumped across the inner mitochondrial membrane when FADH2 is the electron donor than when NADH is the electron donor. FADH2 is made only in the citric acid cycle while NADH is made in glycolysis, acetyl CoA formation, and the citric acid cycle.

Fewer protons are pumped across the inner mitochondrial membrane when FADH2 is the electron donor than when NADH is the electron donor.

Under anaerobic conditions (a lack of oxygen), glycolysis continues in most cells despite the fact that oxidative phosphorylation stops, and its production of NAD+ (which is needed as an input to glycolysis) also stops. The diagram illustrates the process of fermentation, which is used by many cells in the absence of oxygen. In fermentation, the NADH produced by glycolysis is used to reduce the pyruvate produced by glycolysis to either lactate or ethanol. Fermentation results in a net production of 2 ATP per glucose molecule. During strenuous exercise, anaerobic conditions can result if the cardiovascular system cannot supply oxygen fast enough to meet the demands of muscle cells. Assume that a muscle cell's demand for ATP under anaerobic conditions remains the same as it was under aerobic conditions. What would happen to the cell's rate of glucose utilization? Glucose utilization would increase a lot. Glucose utilization would increase a little. Glucose utilization would remain the same. Glucose utilization would decrease a little. Glucose utilization would decrease a lot.

Glucose utilization would increase a lot.

In acetyl CoA formation, the carbon-containing compound from glycolysis is oxidized to produce acetyl CoA. From the following compounds involved in cellular respiration, choose those that are the net inputs and net outputs of acetyl CoA formation. Drag each compound to the appropriate bin. If a compound is not involved in acetyl CoA formation, drag it to the "not input or output" bin. (Note that not all of the inputs and outputs of acetyl CoA formation are included.)

Net Input: Pyruvate Coenzyme A NAD+ Net Output: CO2 NADH Acetyl CoA Not Input or Output: ATP ADP Glucose O2 -In acetyl CoA formation, pyruvate (a product of glycolysis) is oxidized to acetyl CoA, with the reduction of NAD+ to NADH and the release of one molecule of CO2.

In the citric acid cycle (also known as the Krebs cycle), acetyl CoA is completely oxidized. From the following compounds involved in cellular respiration, choose those that are the net inputs and net outputs of the citric acid cycle. Drag each compound to the appropriate bin. If a compound is not involved in the citric acid cycle, drag it to the "not input or output" bin. (Note that not all of the inputs and outputs of the citric acid cycle are included.)

Net input: Acetyl CoA NAD+ ADP Net output: NADH CO2 ATP Coenzyme A Not input or output: Glucose O2 Pyruvate -In the citric acid cycle, the two carbons from the acetyl group of acetyl CoA are oxidized to two molecules of CO2, while several molecules of NAD+ are reduced to NADH and one molecule of FAD is reduced to FADH2. In addition, one molecule of ATP is produced.

From the following compounds involved in cellular respiration, choose those that are the net inputs and net outputs of glycolysis. Drag each compound to the appropriate bin. If the compound is not involved in glycolysis, drag it to the "not input or output" bin.

Net input: Glucose NAD+ ADP Net output: Pyruvate NADH ATP Not input or output: O2 CO2 Acetyl CoA Coenzyme A -In glycolysis, the six-carbon sugar glucose is converted to two molecules of pyruvate (three carbons each), with the net production of 2 ATP and 2 NADH per glucose molecule. There is no O2 uptake or CO2 release in glycolysis.

In the last stage of cellular respiration, oxidative phosphorylation, all of the reduced electron carriers produced in the previous stages are oxidized by oxygen via the electron transport chain. The energy from this oxidation is stored in a form that is used by most other energy-requiring reactions in cells. From the following compounds involved in cellular respiration, choose those that are the net inputs and net outputs of oxidative phosphorylation. Drag each compound to the appropriate bin. If a compound is not involved in oxidative phosphorylation, drag it to the "not input or output" bin. (Note that not all of the inputs and outputs of oxidative phosphorylation are listed.)

Net input: O2 ADP NADH Net output: NAD+ ATP Water Not input or output: CO2 Glucose Coenzyme A Acetyl CoA Pyruvate -In oxidative phosphorylation, the NADH and FADH2 produced by the first three stages of cellular respiration are oxidized in the electron transport chain, reducing O2 to water and recycling NAD+ and FAD back to the first three stages of cellular respiration. The electron transport reactions supply the energy to drive most of a cell's ATP production.

Why is the citric acid cycle called a cycle? The four-carbon acid that accepts the acetyl CoA in the first step of the cycle is regenerated by the last step of the pathway. The acetyl CoA that enters the cycle is regenerated in the last step of the pathway. Citric acid is cycled through the electron transport chain. All of the carbon from glucose is cycled back into the atmosphere as carbon dioxide. NAD+ and FAD are recycled.

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.

During the reaction C6H12O6 + 6 O2 → 6 CO2 + 6 H2O, which compound is reduced as a result of the reaction? Oxygen Water Carbon dioxide Glucose Both glucose and carbon dioxide

oxygen

The final electron acceptor of the electron transport chain that functions in aerobic oxidative phosphorylation is __________.

oxygen

During glycolysis, when each molecule of glucose is catabolized to two molecules of pyruvate, most of the potential energy contained in glucose is

retained in the two pyruvates.


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