BIO 111: Chapter 6

C6H12O6 + 6O2 → 6CO2 + 6H2O + 36ATP is the overall equation for what process?

aerobic respiration

If oxygen is present, most of the known organisms on Earth use the energy pathway ______, which generates the highest amount of ATP of all the energy pathways.

aerobic respiration

What cellular process uses glucose and oxygen to produce ATP?

aerobic respiration

How is ATP formed during the Krebs cycle?

substrate-level phosphorylation

When the electron carrier molecules NADH and FADH2 enter ______, electrons are removed, and the energy pumps protons into the intermembrane compartment of the mitochondrion.

the electron transport chain

How many molecules of ATP are produced in the Krebs cycle per every two molecules of acteyl CoA that enter the Krebs cycle?

2 ATP

Although the theoretical yield of ATP per one molecule of glucose in aerobic respiration is about 36 ATP, the actual yield is about ______ ATP per glucose.

30

The oxidation of glucose during aerobic respiration yields ATP, NADH, and FADH2 molecules. In theory, the ATP yield during the electron transport chain is ______ molecules of ATP per NADH and ______ molecules of ATP per FADH2.

3; 2

Select all of the following that are reactants of pyruvate oxidation during the "transition step" of cellular respiration.

NAD+ pyruvate

During fermentation, ______ reduces pyruvate and is oxidized to NAD+, which can then be used in glycolysis.

NADH

Select all of the following that have been produced from the original glucose molecule after glycolysis, oxidation of pyruvate, and the Krebs cycle occur, but before molecules enter the electron transport chain.

NADH ATP FADH2 CO2

The electron transport chain harnesses the potential energy of the molecules ______, which donate electrons to proteins in the electron transport chain.

NADH and FADH2

The molecules ______ that are produced by glycolysis and the Krebs cycle must move to the inner mitochondrial membrane to enter the electron transport chain.

NADH and FADH2

The rearrangement and oxidation of intermediates in the Krebs cycle transfers electrons to what molecules?

NADH and FADH2

The first protein in the electron transport chain accepts electrons from ______, and the second protein in the electron transport chain accepts electrons from ______.

NADH; FADH2

Select all of the following that cause the difference between the theoretical and actual yields of ATP in aerobic respiration.

Protons leak across the inner mitochondrial membrane without using ATP synthase. ATP is spent transporting pyruvate and ADP into the mitchondrial matrix.

Select all of the following that are true about alcoholic fermentation.

Pyruvate is converted to ethanol and CO2. NAD+ is produced.

In the anaerobic energy pathway called ______, pyruvate from glycolysis is reduced, NADH is oxidized, and NAD+, ethanol, and CO2 are produced.

alcoholic fermentation

Prokaryotic organisms that use NO3-, SO42-, and CO2 as final electron acceptors in an energy pathway that generates ATP are conducting what energy pathway?

anaerobic respiration

Plants conduct photosynthesis. Which of the following conduct cellular respiration?

animals and plants

The first product of the Krebs cycle is the 6-carbon molecule citrate; hence, the Krebs cycle is also known as the ______ cycle.

citric acid

The organic product of photosynthesis, ______, is the reactant of cellular respiration. Multiple choice question.

glucose

The polysaccharides starch and glycogen are broken down during digestion into ______ monomers, which can enter cellular respiration to generate ATP.

glucose

What increases the surface area of the inner mitochondrial membrane?

cristae

If there are sufficient levels of ATP, organisms may store potential energy by diverting acetyl CoA away from the Krebs cycle and storing it as ______ molecules.

fat

The glycerol and fatty acid components of ______ molecules present in food can be converted into pyruvate and acetyl CoA, respectively, which then enter the pathways of aerobic respiration.

fat

______ have more calories per gram than any other food because a single molecule can yield dozens of acetyl CoA molecules that can enter the Krebs cycle.

fats

Two pathways that cells use to make ATP from glucose without oxygen are anaerobic respiration and

fermentation

Select the two energy pathways that generate ATP from glucose without requiring oxygen.

fermentation (with glycolysis) anaerobic respiration

Cellular respiration harvests energy from ______ and uses the energy to power the synthesis of ______ from ADP and a phosphate group.

food molecules; ATP

Before the NADH and FADH2 produced during glycolysis and the Krebs cycle are "cashed in" during the electron transport chain, the net number of ATP molecules produced per glucose molecule is ______ molecules.

four

Select all of the molecules that are reactants of glycolysis.

glucose NAD+

Aerobic respiration captures energy from the oxidation of ______ and reduction of ______ and stores the captured energy in the bonds of ATP.

glucose; oxygen

During what step of cellular respiration is glucose split into two 3-carbon pyruvate molecules?

glycolysis

Select all of the following steps of cellular respiration that generate ATP by substrate-level phosphorylation—that is, without a proton gradient.

glycolysis Krebs cycle

Approximately 32% of the potential energy in a molecule of glucose is captured in ATP through aerobic respiration; the remainder is lost as

heat

In fermentation, ______ produced by glycolysis is reduced, and ______ is regenerated, which allows glycolysis to continue to produce a small amount of ATP.

pyruvate; NAD+

Cellular respiration is an oxidation-reduction reaction that ______ energy, which the cell uses to synthesize ______.

releases; ATP

Select all of the following that are true of ATP synthesis.

requires an input of energy (endergonic reaction) a phosphate group is added to ADP

In the electron transport chain, electrons are shuttled through a series of membrane proteins, which creates a gradient of ______ ions across the inner mitochondrial membrane.

hydrogen

In the electron transport chain, energy from electron transfers powers the pumping of ______ into the intermembrane compartment by some of the proteins in the chain.

hydrogen ions

Glycolysis can occur

in both aerobic and anaerobic conditions.

The Krebs cycle not only produces ATP and electron carriers, but intermediate molecules formed in the Krebs cycle can also be used

in pathways that manufacture amino acids or fats.

Select organisms that are able to generate ATP by conducting anaerobic respiration, which includes an electron transport chain with an inorganic molecule other than oxygen as the final electron acceptor.

some archaeans some bacteria

Select all the food molecules that can be broken down into glucose monomers, which enter aerobic respiration at the beginning of glycolysis.

starch glycogen

What method is used to generate ATP in glycolysis?

substrate-level phosphorylation

True or false: Plants use a portion of the glucose they produce in photosynthesis to make ATP in cellular respiration.

true Reason: Plants use a portion of the glucose they produce in photosynthesis to make ATP in cellular respiration.

Within mitochondria, the electron transport chain and ATP synthase proteins are located in the

inner mitochondrial membrane.

The area between the outer and inner membranes of a mitochondrion is called the ______ compartment.

intermembrane

How do organisms make ATP?

using potential energy stored in molecules

When there is no oxygen available to human muscle cells, the cells can continue to make ATP for a short time using glycolysis as part of

lactic acid fermentation.

The anaerobic respiration pathway generates

less ATP than aerobic respiration.

The fluid enclosed within the inner membrane of a mitochondrion is called the

matrix.

What organism conducts alcoholic fermentation?

yeast

Select all the types of organisms that can rely on fermentation as the sole pathway for producing ATP.

microorganisms in sugar-rich environments single-celled organisms

Select all the organelles that contain electron transport chains within their inner membranes or inner compartments and that are likely to have arisen from endosymbiosis of bacteria with electron transport chains on their cell membranes.

mitochondria chloroplasts

In the cells of protists, plants, fungi, and animals, the Krebs cycle and the electron transport chain take place in organelles called

mitochondria.

Pyruvate is the product of glycolysis, and after it moves into the ______, it is oxidized to form ______ that enters the Krebs cycle. Multiple choice question.

mitochondrial matrix; acetyl CoA

What organelle in a eukaryotic cell provides most of the cell's ATP?

mitochondrion

Muscle soreness in humans is not likely due to a pH drop from fermentation because

muscle cells produce lactate, not lactic acid.

When carbohydrate supplies are depleted in cells, amino acids from proteins can enter aerobic respiration after ______ is removed from the amino acid and excreted.

nitrogen

In aerobic respiration, the final electron acceptor, ______, combines with hydrogen ions to form water.

oxygen

What byproduct of photosynthesis is used as the final electron acceptor of aerobic respiration?

oxygen

Specialized organs such as gills or lungs help many organisms acquire what gas that is required for aerobic cellular respiration?

oxygen (O2)

In substrate-level phosphorylation, a molecule donates a(n) ______ group to ADP to form ATP, and a ______ is not required.

phosphate; proton gradient

Select all of the following that are encoded by mitochondrial DNA.

proteins of the electron transport chain ATP synthase

Enzymes separate the glycerol and fatty acids of fats in food molecules; then the glycerol is converted to ______, which is able to enter aerobic respiration.

pyruvate

In glycolysis, a glucose molecule is split into two molecules of ______, and energy is harvested as ATP and NADH.

pyruvate

Match each product or result with its type of anaerobic respiration.

- H2S byproduct: wetland bacteria that use SO42- as the electron acceptor in anaerobic respiration - generate methane: archaea inside cow intestines that is CO2 as the electron acceptor in aerobic respiration -Result in production of nitrogen gas: bacteria living in water-logged soils that use NO3- as the electron acceptor in aerobic respiration

Match the aerobic respiration step with the correct location where it occurs in the cell in prokaryotes (bacteria and archaea) and eukaryotes.

- Krebs cycle in prokaryotes: cytosol - Krebs cycle in eukaryotes matches: mitichandrial matrix - electron transport in prokaryotes matches - electron transport in eukaryotes matches: inner mitochondrial membrane inner mitochondrial membrane

Rank the types of metabolic pathways from smallest ATP production (at the top) to largest production of ATP (at the bottom). Position 1 of 3 aerobic respiration incorrect toggle button unavailable aerobic respiration

1. fermentation (with glycolysis) 2. anaerobic respiration 3. aerobic respiration

Rank the 3 groups of reactions of aerobic respiration in the order they occur, beginning with the first stage of cellular respiration at the top.

1. glocolysis 2. Krebs cycle 3. Electrons transport chain

Select reactions that occur during the first stage of glycolysis, called the energy investment stage, which consists of the first five reactions.

A 6-carbon intermediate is split into two 3-carbon molecules. Phosphate is transferred to glucose.

ATP synthase is an enzyme that forms a channel for hydrogen ions to diffuse across a membrane and power the formation of

ATP

Mutations to mitochondrial DNA may cause severe disorders if the genes that code for electron transport proteins or ATP synthase are affected because ______ may not be generated.

ATP

Organisms in oxygen-rich environments use aerobic cellular respiration to generate

ATP

The potential energy stored in food (such as glucose) is used by all organisms to make the energy-carrying molecule _____ , which powers cellular activity.

ATP

What molecule powers most energy-requiring cell activities, including active transport, movement of chromosomes and flagella, muscle contraction, and the synthesis of organic molecules?

ATP

Select all of the following that are required for glycolysis to occur.

ATP glucose

Select all of the following that are products in the overall equation for aerobic respiration.

ATP (adenosine triphosphate) CO2 (carbon dioxide)

Select reactions that occur during the second stage of glycolysis, called the energy harvest stage and consisting of reactions 6 through 10.

ATP is generated by substrate-level phosphorylation. NAD+ is reduced to NADH. Two molecules of pyruvate are produced.

What enzyme uses the energy of a proton gradient to add a phosphate to ADP?

ATP synthase

Glycolysis generates 4 --- molecules per glucose, but requires an input of ---- ATP molecule(s), producing a net of 2 ATP molecules per glucose.

ATP; TWO

Anaerobic respiration and fermentation are two pathways that generate ______ in the absence of ______.

ATP; oxygen

Match the organisms and their correct method for obtaining oxygen and releasing carbon dioxide during cellular respiration.

Bacteria: Gases diffuse across cell membrane Shark: Blood is circulated through gills, and water passing by blood vessels causes diffusion of oxygen into blood vessels and diffusion of carbon dioxide out of blood vessels Human: inhaling and exhaling of air causes diffusion of oxygen into blood vessels and diffusion of carbon dioxide out of blood vessels at the lungs

Select all of the products of cellular respiration that are used as reactants in photosynthesis.

CO2 H2O

Select all of the following that are products of the "transition step" in aerobic cellular respiration.

CO2 acetyl CoA NADH

Aerobic cellular respiration requires that ______ diffuses out of cells, and ______ diffuses into cells.

CO2; O2

What happens to the lactate produced by muscle cells that conduct fermentation to acquire ATP?

Cells consume it within a short time.

Why do scientists think glycolysis was probably the first energy pathway to evolve?

Glycolysis is conducted by nearly all organisms.

Select all the products of glycolysis and the Krebs cycle that carry electrons to the electron transport chain in aerobic respiration.

FADH2 NADH

Select the molecules that are products of the Krebs cycle.

FADH2 carbon dioxide ATP NADH

Select all of the electron-carrier molecules produced by the Krebs cycle.

FADH2 (flavin adenine dinucleotide) NADH (nicotinamide adenine dinucleotide)

True or false: Glucose is the only food molecule that can enter the pathways of aerobic respiration and lead to the production of ATP.

False Reason: Proteins, lipids, and polysaccharides, such as starch, are able to enter the pathway of aerobic respiration at different stages.

Intermediates from what pathway can be used in the manufacture of amino acids and fats?

Krebs cycle

Select all of the following that are stages of aerobic cellular respiration.

Krebs cycle glycolysis electron transport chain

In lactic acid fermentation, NADH reduces pyruvate, and the products are ______ and lactic acid.

NAD+

True or false: Plants use a portion of the glucose they produce in photosynthesis to make ATP in cellular respiration. True false question.

True Reason: Plants use a portion of the glucose they produce in photosynthesis to make ATP in cellular respiration.

True or false: The potential energy stored in glucose cannot be removed all at once or it will cause destruction of the cell.

True Reason: Removal of all the potential energy stored in glucose must occur in a series of reactions.

The potential energy of ______ is used to power the production of ATP in chemiosmotic phosphorylation.

a proton gradient

What molecule carries potential energy originally present in the chemical bonds of glucose and enters the Krebs cycle?

acetyl CoA

What product of pyruvate oxidation enters the Krebs cycle?

acetyl CoA

After nitrogen is removed from the amino acids in protein-containing foods, the remainder of the amino acids can enter aerobic respiration pathways as what molecules?

acetyl CoA an intermediate in the Krebs cycle pyruvate

Select all of the cellular activities that require ATP.

active transport protein synthesis cell movement

Select molecules that have stored potential energy and that can be used in aerobic respiration to generate ATP.

carbohydrates proteins lipids

The Krebs cycle produces ATP, NADH, FADH2, and releases ______, which contains the carbon atoms remaining from the original 6-carbon glucose molecule.

carbon dioxide

Select all of the following that can be a final electron acceptor in anaerobic respiration.

carbon dioxide sulfate nitrate

Glycolysis occurs in the ______ of all living cells.

cytosol Reason: The Kreb's Cycle occurs in the mitochondria, but glycolysis occurs in the cell cytosol. The products of glycolysis move into the mitochondria to participate in the rest of aerobic respiration.

In what step of aerobic cellular respiration do electrons pass through a series of membrane proteins, and the energy released by their passage is used to create a hydrogen ion gradient?

electron transport chain

What pathway of aerobic cellular respiration generates ATP by chemiosmotic phosphorylation?

electron transport chain

What step of aerobic respiration generates the most ATP?

electron transport chain

NADH and FADH2 transfer energy-rich ______ from the molecules of glycolysis and the Krebs cycle to the electron transport chain of aerobic respiration.

electrons Reason: Electrons are transported to add a 'P' to 'ADP' to make ATP.

Chloroplasts and mitochondria, the sites of photosynthesis and cellular respiration, are thought to have arisen by

endosymbiosis of bacterial cells.

Alcoholic fermentation produces a molecule called

ethanol