In the Tricarboxylic acid (TCA) cycle, there are specific points where oxidations occur. Which of the following steps involves the reduction of FAD ⁺ to FAD H₂ rather than NAD ⁺ to NADH + H ⁺ ?

Step-by-step solution

In the TCA cycle, there are three points where NAD ⁺ is reduced to NADH + H ⁺ and one point where FAD ⁺ is reduced to FADH₂ . The reduction of FAD ⁺ to FADH₂ occurs specifically during the oxidation of succinic acid. The conversions of isocitrate to -ketoglutaric acid, -ketoglutaric acid to succinyl-CoA, and malic acid to oxaloacetic acid are the three steps that involve the reduction of NAD ⁺ to NADH + H ⁺ . Answer: Oxidation of succinic acid