Question

How many ATP molecules are needed as an initial investment in the glycolytic cycle (normal glycolysis)?

• A. 1.
• B. 2.
• C. 3.
• D. 4.

Hint:

In glycolysis, 2 ATP molecules are invested during the energy investment phase, but a net gain of 2 ATP is achieved after the process.

Answer 1

The Correct Option is B

Step 1: Understanding ATP investment in glycolysis.
The initial phase of glycolysis involves glucose phosphorylation to glucose-6-phosphate, requiring one ATP. Subsequently, a second ATP is expended to convert fructose-6-phosphate into fructose-1,6-bisphosphate.Step 2: ATP molecules utilized.
Two ATP molecules are consumed in the energy-requiring initial stage of glycolysis: 1. Glucose is converted to glucose-6-phosphate, utilizing one ATP. 2. Fructose-6-phosphate is converted to fructose-1,6-bisphosphate, utilizing one ATP.\[\therefore \text{The correct answer is: 2.}\]