[vuoreksensanomat]

My professor says it. However, I have difficulty in accepting it, since the thing has NADH/NAD+ as exchanging electrons so in my opinion redox reactions should happen.

Why does no redox reactions happen in the Citric acid cycle?

[Dan]

You are correct, and your Professor s wrong. The citric acid cycle is full of redox chemistry! NAD⁺ or FAD are oxidising agents that oxidise the intermediates of the cycle, and are themselves reduced (to NADH.H⁺ and FADH₂, respectively) in the process - as you have pointed out, this is clearly redox.