Question

How many ATP are formed through substrate level phosphorylation from one molecule of glucose when it is completely oxidised?

• A. 6
• B. 8
• C. 2
• D. 4

Answer 1

The correct option is A

6

The correct option is A.

Explanation for correct option :

1. During glycolysis, four molecules of ATP are generated from one molecule of glucose, and two molecules of ATP are formed in two Krebs cycles through substrate-level phosphorylation.
2. The phosphate group is transported straight from a substrate to ADP, resulting in ATP.
3. The following are some of them:
   1. When 1,3-diphosphoglycerate is converted to 3-phosphoglycerate, 2 ATP is produced.
   2. When 2-phosphoenol pyruvic acid converts to pyruvic acid, 2 ATP is produced. When succinyl CoA is converted to succinate, two ATP molecules are produced in two Krebs cycles.
   3. GTP is formed by converting GDP to GTP, which subsequently transfers phosphate to ADP to produce ATP.

Final answer: 6 ATP are formed through substrate-level phosphorylation from one molecule of glucose when it is completely oxidized.