Select the correct order of reactions in glycolysis
(a) 3-Phosphoglyceraldehyde `rarr`1, 3-biphosphoglycerate
(b) 3-phosphoglyceric acid `rarr`2-phospho-glycerate
(c) BPGA `rarr`3-phosphoglyceric acid
(d) Splitting of 1, 6-fructose biphosphate to dihdroxy acetone phosphate and 3-phosphoglyceraldehyde

Options

A. d, a, c, b
B. b, c, a, b
C. b, d, a, c
D. a, d, c, d

Answer

To determine the correct order of reactions in glycolysis, we need to analyze the provided reactions and their sequence in the glycolytic pathway. Glycolysis consists of a series of enzyme-catalyzed reactions that convert glucose into pyruvate, producing ATP and NADH in the process. Here’s how we can break down the question step by step:

### Step-by-Step Solution:

1. **Identify the starting point**: Glycolysis begins with glucose and ends with pyruvate. The first step we need to consider is the splitting of fructose 1,6-biphosphate.

2. **Reaction (d)**: The splitting of fructose 1,6-biphosphate into dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (G3P) is the first reaction in the sequence. This is a key step in glycolysis and is catalyzed by the enzyme aldolase.

3. **Reaction (a)**: After the splitting, glyceraldehyde 3-phosphate (G3P) is converted into 1,3-bisphosphoglycerate (1,3-BPG). This reaction is catalyzed by the enzyme glyceraldehyde 3-phosphate dehydrogenase.

4. **Reaction (c)**: Next, 1,3-bisphosphoglycerate is converted into 3-phosphoglycerate (3-PG). This reaction is catalyzed by phosphoglycerate kinase.

5. **Reaction (b)**: Finally, 3-phosphoglycerate is converted into 2-phosphoglycerate (2-PG). This reaction is catalyzed by phosphoglycerate mutase.

### Correct Order of Reactions:
Based on the above analysis, the correct order of reactions in glycolysis is:
- (d) Splitting of 1,6-fructose biphosphate to dihydroxyacetone phosphate and 3-phosphoglyceraldehyde
- (a) 3-Phosphoglyceraldehyde → 1, 3-biphosphoglycerate
- (c) 1, 3-biphosphoglycerate → 3-phosphoglyceric acid
- (b) 3-phosphoglyceric acid → 2-phosphoglycerate

Thus, the correct sequence is: **d, a, c, b**.

### Final Answer:
The correct order of reactions in glycolysis is **(d) → (a) → (c) → (b)**.