Question

Assuming 1.5 ATP per FADH, 2.5 ATP per NADH in mitochondria, compare
approximately how many ATP equivalents would be required to build  - starting with CO₂ -

a. two molecules of glucose (12 C)

b. 12 C saturated fatty acid

Answer 1

a) In C3 plants , 12 Calvin cycles will be required to form 2 glucose molecules. Each Calvin cycle require 3Atp and 2 NADPH. So, total required = 36 ATP and 24 NADPH ,

As NADH form 2.5 ATP fromthe given data, NADPH will form 3.5 ATP.,

So total ATP required =36+84 ATP = 120 ATP.

For fatty acid chain 12 C . The carbon are added in pairs, each pair form 5 bonds for forming 12 C product and for each bond 1 ATP and 1 NADH will be required.

5 NADH and 5 ATP will be required. So, total ATP required will be = 12.5 + 5 ATP = 17.5 ATP required.