Biology - Chapter 6

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

ATP; oxygen

What step of aerobic respiration generates the most ATP?

Electron transport chain

What is the final electron acceptor of aerobic respiration?

Oxygen

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

NADH

The electron transport chain accepts energy-rich electrons from ______ and ______ produced in the previous reactions of aerobic respiration.

NADH FADH2

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

NADH and FADH2

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

NO3- SO42-

What cellular process generates ATP and uses an inorganic molecule other than oxygen as the final electron acceptor of an electron transport chain?

anaerobic respiration

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

anaerobic respiration fermentation (with glycolysis)

At the beginning of the Krebs cycle, acetyl CoA loses its coenzyme, and the two-carbon acetyl group combines with a four-carbon molecule, producing a six-carbon molecule called

citrate.

The folds of the inner mitochondrial membrane are called ______, and they greatly increase the surface area of the inner membrane.

cristae

Glycolysis occurs in the ______ of all living cells.

cytosol

In what pathway is ATP produced in glycolysis but the NADH product of glycolysis does not enter an electron transport chain?

fermentation

Cellular respiration harvests the potential energy stored in ______ and uses the energy to make ATP.

food moecules

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

four; two

The polysaccharides starch and glycogen can be broken down into what monomer that enters the cellular respiration pathway?

glucose

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

glucose ATP

Select all of the molecules that amino acids can be converted to when entering the energy pathways of cellular respiration.

pyruvate an intermediate in the Krebs cycle acetyl CoA

In the electron transport chain, electrons are shuttled through a series of membrane proteins, which creates a gradient of

hydrogen ions.

Glycolysis can occur

in both aerobic and anaerobic conditions

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

starch glycogen

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

matrix

In eukaryotes, the oxygen-requiring reactions of aerobic cellular respiration occur in cellular organelles called

mitochondria

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

mitochondrial matrix; acetyl CoA

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

nitrogen

The reactions of the Krebs cycle ______ citrate as they produce ______.

oxidize; CO2, NADH, and FADH2

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

oxygen

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

proteins lipids carbohydrates

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

pyruvate

Select all of the molecules that are reactants of glycolysis.

NAD+ glucose

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. glycolysis 2. Krebs cycle 3. Electron transport train

Using an input of energy from food molecules, the reactions of cellular respiration produce ______.

ATP

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

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

In the last stage of cellular respiration, protons moving down their concentration gradient back into the mitochondrial matrix through ______ drive the production of ATP.

ATP synthase

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

ATP synthase

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

aerobic respiration

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

CO2 (carbon dioxide) ATP (adenosine triphosphate)

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

CO2; O2

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.

FADH2 NADH CO2 ATP

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

During which step of aerobic respiration is glucose split into two 3-carbon molecules?

Glycolysis

In aerobic respiration, what process produces CO2, ATP, and electron carrier molecules?

Krebs cycle

Select all of the following that are biochemical pathways of aerobic cellular respiration.

Krebs cycle electron transport chain glycolysis

Select all of the following that are produced during the pathway of alcoholic fermentation.

NAD+ CO2 ethanol

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

True

What cellular process uses glucose and oxygen to produce ATP?

aerobic respiration.

The fatty acids of fat molecules are converted into two-carbon molecules called ______, which can enter the Krebs cycle of aerobic respiration.

acetyl CoA

What product of pyruvate oxidation enters the Krebs cycle?

acetyl CoA