Question

If one triose phosphate completely oxidized inside prokaryotic cell than gain of ATP of energy equal to?

• A. $5$ ATP
• B. $4$ ATP
• C. $20$ ATP
• D. $19$ ATP

Answer 1

The correct option is D $19$ ATP

Triose phosphate is another name of glyceraldehyde 3- phosphate

Total NADH and ATP are produced in the cycle are as follows as -

Name of process	Gain of ATP
Glycolysis: glyceraldehyde 3- phosphate $\to$ pyruvate	1 NADH ( each NADH is equal to 3 ATP) + 1 ATP 3ATP+ 1ATP = 4ATP
Oxidative decarboxylation pyruvate $\to$ acetyl CoA	1 NADH = 3 ATP
Tricarboxylic acid cycle	3NADH +1 FADH (each FADH is equal to 2ATP) + 1 GTP(equivalent to ATP) = 12 ATP

Total gain of ATP, when one triose phosphate is completely oxidised = 4 ATP =3 ATP =12 ATP $\to$ 19 ATP

So, the correct answer is ' 19 ATP '