SB Ch 6.6-6.8 Respiration and Fermentation

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

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. Multiple choice question.

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? Multiple choice question.

2 ATP

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

NADH

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

NADH and FADH2

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

If a cell's carbohydrate supplies run low, ______ monomers of proteins can be converted into molecules that enter the pathways of cellular respiration.

amino acid

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

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

anaerobic respiration

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

anaerobic respiration fermentation (with glycolysis)

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

glucose

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

glucose

The monomers of starch and glycogen food molecules first enter aerobic respiration at what step? Multiple choice question.

glycolysis

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

citric acid

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

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

fermentation

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

glycogen starch

the monomers of starch and glycogen food molecules first enter aerobic respiration at what step?

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

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?

pyruvate acetyl CoA an intermediate in the Krebs cycle

In the energy pathway called lactic acid fermentation, ______ is reduced to lactic acid, and NADH is oxidized to NAD+, which allows ______ to continue producing a small amount of ATP. Multiple choice question.

pyruvate; glycolysis

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

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

sulfate nitrate carbon dioxide

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 Multiple choice question.

less ATP than aerobic respiration.

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

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

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

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

proteins lipids carbohydrates

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. Multiple choice question.

4

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

ATP; oxygen

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.

CO2 FADH2 ATP NADH

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

NAD+

What happens to the carbon atoms in the two-carbon acetyl group that enters the Krebs cycle?

They are released as CO2.

What happens to the carbon atoms in the two-carbon acetyl group that enters the Krebs cycle? Multiple choice question.

They are released as CO2.

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

a proton gradient

What product of pyruvate oxidation enters the Krebs cycle?

acetyl CoA

When protons diffuse across a membrane through ATP synthase, energy is transferred to phosphorylate an ADP, making ATP in the process called ______ phosphorylation.

chemiosmotic

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

What step of aerobic respiration generates the most ATP? Multiple choice question.

electron transport chain

Alcoholic fermentation produces a molecule called Multiple choice question.

ethanol.