First stage in respiration is

Options

A. Aerobic oxidation of pyruvic acid
B. Liberation of `CO_2`
C. Glycolysis
D. Electron transport system

Answer

C

Explanation

First stage of respiration is glycolysis i.e. breakdown of glucose. It occurs in the cytoplasm of the cell and is present in all living organisms it is defined as the process of partial oxidation of glucose to form two molecules of pyruvic acid.