Question

Describe various pathways of glucose break down in organisms.

Answer 1

First, glycolysis of glucose takes place in the cytoplasm of the cell, which forms three-carbon pyruvate molecule and energy.

Then one of the two types of respiration takes place:

1) Aerobic respiration: This type of respiration takes place in normal body cells of living organisms. It takes place in mitochondria of the cells. Here, pyruvate breaks down into carbon dioxide, water and energy, in the presence of oxygen.

2) Anaerobic respiration: This type of respiration takes place if there is a lack of oxygen, for example in muscle cells. This process takes place in the cytoplasm of the cell and produces lactic acid and energy.

Fermentation: It is a type of anaerobic respiration, which takes place in absence of oxygen. Here, pyruvate breaks down to form ethanol, carbon dioxide and energy.

This type of respiration is observed in yeast cells