Chapter 9: Cellular Respiration

33.) Why is the total count about 36 or 38 ATP rather than a specific number?

In can change in oxidative phosphorylation, depending on which shuttle transports the electrons from NADH back to the cytosol.

For aerobic respiration to continue, the cell must be supplied with oxygen (the ultimate electron acceptor). What is the electron acceptor in fermentation?

NAD+.

Each NADH can form a maximum of ____ ATP molecules. Each FADH2, which donates electrons that activate only two proton pumps, makes ____ ATP molecules.

3, 2.

In cellular respiration, electrons are not transferred directly from glucose to oxygen. Each electron is coupled with a proton to form a hydrogen atom. Following the movement of hydrogen's allows you to follow the flow of electrons. The hydrogen's are held in the cell temporarily by what electron carrier?

A coenzyme called: NAD+.

What is the function of the electron transport chain in cellular respiration?

A sequence of electron carrier molecules (membrane proteins) shuttle electrons during the redox reactions that release energy used to make ATP.

What is a coenzyme?

An organic molecule serving as a cofactor. Most vitamins function as coenzymes in important metabolic reactions.

Explain how a MP stimulates cellular respiration while citrate and ATP inhibit it.

As ATP is used up, AMP accumulates which signals more ATP to be made. The more ATP there is, the slower glycolysis is.

Explain the difference in energy usage between the catabolic reactions of cellular respiration and anabolic Pathways of biosynthesis.

Cellular respiration energy is converted to synthesize ATP. Biosynthesis energy from ATP is used to synthesize more complex molecules.

Explain what happened to the six-carbon molecules found in the original glucose molecules.

Each six-carbon molecule has been broken down into two 3-carbon molecules.

Explain the difference between fermentation and cellular respiration?

Fermentation is without oxygen. Cellular respiration is referring to aerobic respiration. Some prokaryotes use other substances instead of oxygen. Is with Oxygen.

Give the formula (with names) for the catabolic degradation of glucose by cellular respiration.

Glucose + 6 Water --> 6 Carbon dioxide + 6 Water + Energy (ATP + heat).

Show the normal, downhill route most electrons follow in cellular respiration:

Glucose --> NADH --> electron transport chain --> oxygen.

12.) Why is glycolysis an appropriate term this step of cellular respiration?

Glycolysis means sugar splitting- in the reaction a six-carbon sugar is split into two 3-carbon sugars.

The step that converts pyruvate to acetyl CoA at the top of the diagram also occurs twice per glucose. This step accounts for two additional reduced ___________ molecules and two carbon dioxide molecules.

NAD+.

The two electron carrier molecules that feed electrons into the electron transport system are ________and ________.

NADH and FADH2.

Both cellular respiration and photosynthesis are redox reactions. In redox reactions, pay attention to the flow of electrons. What is the difference between oxidation and reduction?

Oxidation is the loss of electrons from one substance. Reduction is the addition of electrons to another substance.

What three organic macromolecules are often utilized to make ATP by cellular respiration?

Proteins, carbohydrates, and fats / lipids.

Explain how lactic acid fermentation starts with glucose and yields lactate.

Pyruvate converted to lactate allowing NADH to go there which also allows NAD+ to be recycled.

Explain how alcohol fermentation starts with glucose and yields ethanol.

Pyruvate loses a carboxyl group coming out as CO2 making it ethyl alcohol, which allows NAD+ to go there so the NADH can be "recycled"

Explain how the electron transport chain is utilized in oxidative phosphorylation.

The electron transport chain powers the oxidative phosphorylation.

The following is a generalized formula for a redox reaction: Which part is oxidized and which is reduced?

Xe- + Y--> X + Ye- (Xe- is the part that's oxidized, Ye- is the part that's reduced.)

How many molecules of the following are formed from the breakdown of glucose: a.) NADH: b.) FADH2: c.) ATP:

a.) 2. b.) 2. c.) 2.

In the citric acid cycle: a.) How many NADH's are formed? b.) How many total carbons are lost as pyruvate is oxidized? c.) The carbons have been lost as the molecule ________? d.) How many FADH2's have been formed? e.) How many ATP's are formed?

a.) 3 per pyruvate. b.) 2 per pyruvate. c.) carbon dioxide. d.) 1 per pyruvate. e.) 1 per pyruvate.

Notice that glycolysis occurs in the ___________ of the cell. What is the relationship concerning glycolysis and oxygen?

cytosol. Glycolysis happens whether or not oxygen is present. If oxygen is present the chemical energy stored in pyruvate and NADH can be extracted by the citric acid cycle and be converted to oxidative phosphorylation.

When compounds lose electrons, they ________________ energy; when compounds gain electrons, they _______________ energy.

gain, lose (opposite).

The starting product of glycolysis is the six-carbon sugar ____________, and the ending product is two _________ carbon compounds termed ____________.

glucose, three, pyruvate.

Fermentation allows for the production of ATP without using either ____ or any _____.

oxygen, electron transport chain.