Question

Arrange the enzymes of glycolysis in correct order? A. Hexokinase B. Glyceraldehyde-3-phosphate dehydrogenase C. Aldolase D. Phosphohexose isomerase E. Phosphofructokinase-1 Choose the correct answer from the options given below:

• A. A, D, E, C, B \
• B. D, A, E, C, B \
• C. B, A, E, C, D \
• D. A, B, E, C, D

Hint:

Glycolysis always begins with Hexokinase (A) turning glucose into G6P. The payoff phase is later initiated by Glyceraldehyde-3-phosphate Dehydrogenase (B).

Answer 1

The Correct Option is A

Step 1: Concept Glycolysis is a central metabolic pathway consisting of 10 sequential enzymatic steps that break down one molecule of glucose into two molecules of pyruvate.

Step 2: Meaning The pathway is divided into an initial preparatory (investment) phase and a subsequent pay-off phase.

Step 3: Analysis Let us track the first five steps of glycolysis in order: 1. Glucose is phosphorylated by Hexokinase (A) to form Glucose-6-phosphate. 2. Glucose-6-phosphate is converted to Fructose-6-phosphate by Phosphohexose isomerase (D). 3. Fructose-6-phosphate is phosphorylated by Phosphofructokinase-1 (E) to form Fructose-1,6-bisphosphate. 4. Fructose-1,6-bisphosphate is cleaved by Aldolase (C) into two 3-carbon sugars. 5. Glyceraldehyde-3-phosphate is oxidized by Glyceraldehyde-3-phosphate dehydrogenase (B) to initiate the pay-off phase.

Step 4: Conclusion This chronological sequence corresponds to the order A $\rightarrow$ D $\rightarrow$ E $\rightarrow$ C $\rightarrow$ B, matching option A. Final Answer: (A)