Question

in the citric acid cycle (see figure below) beginning with one molecule of isocitrate and ending with fumarate, how many atp molecules can be made through substrate - level phosphorylation? 1 2 11 12 24

Explanation:

Step1: Identify relevant step in cycle

In citric - acid cycle, substrate - level phosphorylation occurs when succinyl - CoA is converted to succinate.

Step2: Determine ATP production

One ATP (or GTP which is equivalent in energy terms) is produced during this conversion per molecule of succinyl - CoA. From isocitrate to fumarate, this substrate - level phosphorylation step occurs once.

Answer:

1