Question

In aerobic cellular respiration, what three major steps are involved?

Answer 1

Three major steps in cellular respiration are:. Glycolysis, Kreb's cycle and oxidative phosphorylation.

Explanation:

Cellular respiration involves 3 major steps:
1. Glycolysis
2. Kreb's cycle or Citric acid cycle
3. Oxidative phosphorylation.

Glycolysis - Glucose is main substrate . It enters glycolysis as fructose 1:6 diphosphate. It is broken down into 2 molecules of 1:3 di- phosphoglyceric acid. It is converted into phosphoglyceric acid.

Kreb's cycle - Phosphoglyceric acid is converted into phospho-enol-pyruvic acid. During cyclic reactions of citric acid cycle, phospho-enol-pyruvic acid is completely oxidized. `NADPH + H` or `NADPH2` are produced.

Oxidative phosphorylation -During this step, `NADPH2` is oxidized to produce ATP molecules.