Chapter 16, Problem 1P

Interpretation Introduction

Interpretation:

The correct option from the given is to be selected which gives the net synthesis due to conversion of one molecule of fructose-6-phosphate into 2 molecules of pyruvate.

Concept introduction:

Glycolysis, also termed as Embden-Meyerhof pathway, is an oxidative pathway, in which, one mole of glucose is converted into two moles of pyruvate. Glycolysis occurs in the cytosol of the cells. It occurs in both aerobic and anaerobic organisms and does not include molecular oxygen.

Answer to Problem 1P

Among the answers given, the correct answer is option (d), four molecules of ATP and two molecules of NADH.

Explanation of Solution

Given:

1. Two molecules of NADH and two molecules of ATP.
2. Two molecules of NAD+ and two molecules ATP.
3. Four molecules of NADH and four molecules of ATP.
4. Two molecules of NADH and four molecules of ATP.

Reason for the correct option:

Option (d) is four molecules of ATP and two molecules of NADH. Glycolysis is divided into two phases, the preparatory phase, and payoff phase. In the preparatory phase, two moles of ATP are used, while in payoff phase, four moles of ATP are and 2 moles of NADH are formed. So, overall in the glycolysis process, 2 ATP molecules are produced and 2 NADH molecules are produced. In the glycolysis, when one molecule of fructose-6-phosphate is converted into two molecules of pyruvate, then four moles of ATP are and 2 moles of NADH are formed. Hence, this option is correct.

Conclusion

Reason for incorrect options:

Option (a) is two molecules of NADH and two molecules of ATP. The net result of glycolysis is two molecules of NADH and two molecules of ATP. Hence, this option is incorrect.

Option (b) is two molecules of NAD+ and two molecules of ATP. In glycolysis, two molecules of NAD+ are used up to produce two molecules of NADH. Hence, this option is incorrect.

Option (c) is four molecules of ATP and four molecules of NADH. When fructose-6-phosphate is converted into pyruvate, then four molecules of ATP and two molecules of NADH are produced. Hence, this option is incorrect.