BISC 130 - Chapter 7: Cellular Respiration

What is the main function of cellular respiration?

The complete breakdown and oxidation of glucose to generate ATP.

What is Oxidation?

 When an atom loses an electron, also loses some of its potential energy.

What is Reduction?

When an atom gains an electron, thus gaining potential energy. But since electrons are negative charges, the atom gains ‘negative’ energy.

What are examples of Electron Carriers?

NAD+ (oxidized) and NADH (reduced)

What is the chemical formula for Glucose?

C6 H12 O6

What is the chemical equation for cellular respiration?

C6 H12 O6 + O2 --> CO2 + H2O + energy (ATP)

What are the stages of cellular respiration?

Glycolysis, Pyruvate Oxidation, Citric Acid Cycle, and Electron Transport Chain.

Where does glycolysis take place?

In the cytoplasm.

Explain the use of ATP in Glycolysis

ATP is spent in the earlier stages of glycolysis, resulting in ADP + Pi, but more ATP is generated in later stages from ADP + Pi

What is the end product of glycolysis?

Pyruvate (3-Carbon) and a net amount of ATP.

What is the role of NAD+ in glycolysis?

NAD+ is reduced to NADH during glycolysis as it gains electrons.

What are NAD+ and NADH?

NAD+ doesn’t have many electrons (oxidized), but is capable of taking in electrons. Once it starts taking in a lot of electrons, it turns into NADH (reduced).

What is produced during pyruvate oxidation?

Acetyl-CoA, NADH, and CO2.

In Pyruvate Oxidation, what happens to the two 3-carbon pyruvates?

Each loses a carboxyl group in the form of CO2, and both 2-carbon molecules are attached to Coenzyme A (now collectively known as acetyl CoA).

What happens to the two 2-carbon molecues?

They lose electrons (oxidize), which are then picked up by NAD+ to form NADH. The oxidized molecule then attaches to Coenzyme A

What happens during the Citric Acid Cycle?

Acetyl group is transferred to oxaloacetate to form citrate, which is then oxidized back to oxaloacetate.

What is generated in the Citric Acid Cycle?

ATP, NADH, and FADH2.

What happens to NADH and FADH2 in the Electron Transport Chain?

They are oxidized back to NAD+ and FAD, passing high-energy electrons through a series of carriers.

What creates the proton gradient during cellular respiration?

Energy from electrons is used to pump H+ across the membrane.

What is ATP Synthase?

A large multi-protein complex that allows H+ to pass through, generating ATP.

How do other carbohydrates enter cellular respiration?

They are broken down into monosaccharides, which enter glycolysis.

How are proteins catabolized in cellular respiration?

They are broken into amino acids, which enter glycolysis, pyruvate oxidation, or the citric acid cycle.

What happens to lipids in cellular respiration?

They are broken into 2-Carbon units that enter the citric acid cycle.