Cellular Respiration

What is the purpose of cellular respiration?

To break down complex molecules and synthesize ATP

What type of organisms perform photosynthesis?

Autotrophic organisms.

What do heterotrophic organisms break down to produce ATP?

The reduced compounds of food.

Define a reduced compound in terms of energy.

A compound that has gained electrons and increased in energy.

What is oxidation in the context of cellular respiration?

A decrease in energy where an atom or molecule loses electrons.

What is the summary reaction of aerobic respiration?

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O.

What are the four stages of cellular respiration?

1. Glycolysis, 2. Pyruvate oxidation, 3. Citric acid cycle, 4. Oxidative phosphorylation.

Where does glycolysis occur?

In the cytosol

What is the net output of glycolysis?

2 ATP, 2 NADH, and 2 Pyruvate.

What is substrate-level phosphorylation?

The transfer of a phosphate from a reactant to ADP to form ATP.

What happens during pyruvate oxidation?

Pyruvate is oxidized to form acetate and NADH.

Where does pyruvate oxidation take place?

In the mitochondria matrix

What molecules are generated during the citric acid cycle?

2 ATP, 6 NADH, and 2 FADH₂ per glucose.

What is oxidative phosphorylation?

The process of ATP production through electron transport and chemiosmosis.

What are the high energy electron carriers in cellular respiration?

NADH and FADH₂

What is the final electron acceptor in the electron transport chain?

Oxygen (O₂)

What is the proton motive force?

An electrochemical gradient generated by proton pumping actions in the electron transport chain.

What does chemiosmosis involve?

The conversion of the proton gradient into ATP.

What enzyme complex is responsible for ATP synthesis during chemiosmosis?

ATP Synthase.

Where are the components of the electron transport chain located?

In the inner mitochondrial membrane

What is the role of complexes I, II, III, and IV in the electron transport chain?

To accept and pass electrons down the chain, releasing energy.

How many ATP does NADH produce through the electron transport chain?

Approximately 2.5 ATP

How many ATP does FADH2 produce?

Approximately 1.5 ATP

What is the function of the cristae in mitochondria?

To increase the surface area for ATP production.

What occurs during glycolysis regarding glucose?

Glucose is energized and split into two 3-carbon pyruvates.

Why is the citric acid cycle also called the Krebs cycle?

It is named after Hans Krebs, who discovered the cycle.

What is produced in the mitochondria matrix apart from acetyl coenzyme A?

NADH and carbon dioxide (CO₂)

What happens to the energy released during electron transport?

It is used to pump protons into the intermembrane space, creating a gradient.

What is the role of ADP in ATP synthesis?

It combines with phosphate (P) to form ATP.

What is the significance of the inner mitochondrial membrane?

It houses the proteins of the electron transport chain.

How does ATP synthase work?

It utilizes the flow of protons down the gradient to synthesize ATP from ADP.