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What is True about electron transport chaina) FADH gives 2 ATPb) Entry point of NADH is at complex IIc) NADH gives 3 ATPd) FADH gives 3 ATPe) NADH enters the step 1 of cycle and explain in detail?
NADH enters the step 1 of cycle > FA gives 2 ATP & NADH gives 3 ATP

NADH enters the ETC at complex I and FADH2 enters the ETC at complex II.
According to old calculations one molecule of NADH produces 3 ATPs and molecule of FADH2 produces 2 ATP molecules. However, in recent studies it has been proved that NADH produces 2.5 ATPs and FADH2 produces 1.5 ATP s.