Question

. Explain what happens to glucose during glycolysis and respiration in terms of oxidation and reduction.

Answer 1

NOTE: Glucose is the 6-carbon sugar in the food that breaks down to release energy which is stored in the chemical bonds of ATP in an organism.

Catabolism of Glucose is done by cellular respiration which involves two main steps: 1. Glycolysis and 2. Aerobic respiration.

Explanation:

Glucose is the main Respiration Substrate.The overall process of cellular respiration Oxidizes Glucose molecule to release it's energy, which is stored in ATP molecules.

In the process of Respiration Glucose(C6H12O6) is broken down and the broken down products combines with Oxygen (O2) making Water(H2O); Carbon dioxide (CO2) and Energy (ATP).Here, Glucose is Oxidized and Oxygen is Reduced.

Reaction: C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP.

Glycolysis: It's the first step in cellular respiration and first pathway used in breakdown of glucose to extract energy. There is one redox reaction during Glycolysis in which Glucose is Oxidized and NAD+ accepts the electrons during oxidation and as a result gets reduced.

Here, Glucose is Oxidized into two molecules of 3-carbon Pyruvate and ATP.

Aerobic respiration: It is the second step in cellular respiration where Glucose breaks down & Oxidized further [Pyruvate gets breakdown to Acetyl-CoA & Acetyl-CoA (2- Carbon compound) is Oxidized to CO2 and H2O].

Here, CO2 released is coupled with reduction of NAD+ and Oxidation of Acetyl-CoA; Oxygen is Reduced & donates Hydrogen to form Water.