CH. 6 HOW CELLS RELEASE ENERGY

What are the three kinds of cellular respiration?

Aerobic respiration, anaerobic respiration, and fermentation.

What are the three stages of aerobic cellular respiration?

Glycolysis, Krebs cycle (Citric Acid Cycle), and Electron Transport Chain (ETC)/Oxidative Phosphorylation.

What is the balanced equation for aerobic cellular respiration?

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + 38 ATP

What is glycolysis and where does it occur?

Glycolysis is the first step of respiration that occurs in the cytoplasm, breaking glucose into 2 pyruvate molecules.

What is the net yield of ATP and NADH during glycolysis?

Net yield: 2 ATP, 2 NADH.

What are the two methods of ATP production?

Substrate-level phosphorylation and Oxidative phosphorylation.

What happens during the second stage of aerobic respiration?

The Krebs cycle occurs in the mitochondrial matrix.

What are the yields of ATP, NADH, and FADH₂ during the Krebs cycle?

2 ATP, 6 NADH, 2 FADH₂.

What is the total net ATP yield from aerobic cellular respiration?

38 ATP.

Why do some cells produce only 36 ATP instead of 38?

Because NADH from glycolysis cannot cross the mitochondrial membrane directly.

What is the role of O₂ in respiration?

O₂ is the final electron acceptor in the Electron Transport Chain.

How do carbohydrates enter respiration pathways?

Carbohydrates are converted into glucose.

How do proteins enter respiration pathways?

Proteins are broken into amino acids, entering at various points.

How do lipids enter respiration pathways?

Lipids are broken into glycerol (enters glycolysis) and fatty acids (enter Krebs cycle).

How is anaerobic respiration different from aerobic respiration?

Anaerobic respiration occurs without oxygen and produces less ATP.

What is fermentation?

Fermentation is an anaerobic process that regenerates NAD⁺ for glycolysis.

What are the two types of fermentation and their ATP yield?

Lactic acid fermentation (produces lactate) and Alcoholic fermentation (produces ethanol & CO₂); both produce 2 ATP.