Question

Distinguish between the following:

(a) Aerobic respiration and Anaerobic respiration

(b) Glycolysis and Fermentation

(c) Glycolysis and Citric acid Cycle

Answer 1

(a) Aerobic respiration and Anaerobic respiration

Aerobic respiration		Anaerobic respiration
1.	It uses oxygen for deriving energy.	1.	It occurs in the absence of oxygen.
2.	It occurs in cytoplasm and mitochondria.	2.	It occurs in cytoplasm.
3.	The end products of aerobic respiration are carbon dioxide and water.	3.	The end products of fermentation are ethyl alcohol and carbon-dioxide.
4.	Complete oxidation of respiratory substrate takes place.	4.	Incomplete oxidation of respiratory substrate takes place.
5.	36-38 ATP molecules are produced.	5.	Only 2 ATP molecules are produced.

(b) Glycolysis and Fermentation

	Glycolysis		Fermentation
1.	Glycolysis occurs during aerobic and anaerobic respiration.	1.	Fermentation is a type of anaerobic respiration.
2.	Pyruvic acid is produced as its end product.	2.	Ethanol or lactic acid is produced as its end product.

(c) Glycolysis and citric acid cycle

Glycolysis		Citric acid cycle (Krebs cycle)
1.	It is a linear pathway.	1.	It is a cyclic pathway.
2.	It occurs in the cell cytoplasm.	2.	It occurs in the mitochondrial matrix.
3.	It occurs in both aerobic and anaerobic respiration.	3.	It occurs in aerobic respiration.
4.	One glucose molecule breaks down to generate 2 NADH2 and 2 ATP molecules.	4.	It produces 6 NADH2, 2 FADH2, and 2 ATP molecules on breakdown of two acetyl-coA molecules.