C1.2 Cell Respiration

What is ATP?

ATP is the molecule that distributes energy in cells.

What is the structure of ATP?

ATP consists of adenine, ribose, and three phosphate groups.

What happens during the hydrolysis of ATP?

ATP is converted to ADP and Pi, releasing a small amount of energy.

Phosphorylation

ADP + Pi → ATP

What is the role of ATP in life processes?

ATP is needed for synthesizing macromolecules, active transport, and cellular movement.

What distinguishes aerobic respiration from anaerobic respiration?

Aerobic respiration requires oxygen, while anaerobic respiration does not.

What factors affect the rate of respiration?

Temperature and glucose/oxygen levels can affect the rate of respiration.

What is the role of NAD in cellular respiration?

NAD functions as an electron carrier, undergoing oxidation and reduction during respiration.

What reaction occurs in glycolysis

Glucose (6C) is converted to pyruvate (3C)

What are the byproducts of glycolysis?

2 ATP and 2 NADH

Where does glycolysis occur?

In the cytosol

What occurs during the link reaction of aerobic respiration?

Pyruvate (3C) is oxidized and decarboxylated to form Acetyl CoA (2C)

What are byproducts of the link reaction?

2 CO2 and 2 NADH

Where does the link reaction occur?

Mitochondrial matrix

What reaction occurs in Krebs Cycle?

Oxaloacetate (4C) + Acetyl CoA (2C) → Citrate (6C)

How many of each product does the Krebs cycle produce for one glucose molecule?

4 CO2, 6 NADH, 2 FADH2, 2 ATP

Where does the Krebs cycle occur?

Mitochondrial matrix

What transfers energy to the electron transport chain?

NADH and FADH2 transfer electrons to the electron carrier proteins in the electron transport chain.

How is the concentration gradient created at ETC?

Energy released from electrons is used to pump protons across the inner mitochondrial membrane (matrix → intermembrane space)

What is the role of the proton gradient in ATP synthesis?

The proton gradient created during electron transport is used to synthesize ATP through chemiosmosis.

What protein is used to generate ATP?

ATP synthase (integral protein performing oxidative phosphorylation)

What is the final acceptor of electrons in cellular respiration?

Oxygen is the final electron acceptor in the electron transport chain.

How many ATP are produced in total during cellular respiration?

A total of 38 ATP are produced: 2 from glycolysis, 2 from the Krebs Cycle, and 34 from oxidative phosphorylation.

What occurs after glycolysis in anaerobic conditions?

Fermentation

What are products of fermentation?

Lactate or ethanol

What are byproducts of fermentation?

NAD+ and CO2

Where does fermentation occur?

In the cytoplasm