When a poison such as cyanide blocks the electron transport chain, glycolysis and the citric acid cycle also eventually stop working. Which of the following is the best explanation for this? a) The uptake of oxygen stops because electron transport was inhibited b) They run out of ADP c) A high level of NADH is present in the cell d) Electrons are no longer available from the electron transport chain to power glycolysis and the citric acid cycle e) NAD⁺ and FAD are not available for glycolysis and the citric acid cycle to continue

NAD⁺ and FAD are not available for glycolysis and the citric acid cycle to continue.

Explanation:

The glycolysis, citric acid cycle and the Electron transport chain all together makes up the aerobic respiration. The glycolysis and Kreb's Cycle produces a lot of reduced hydrogen ion transporters like NADH and FADH which are then transported to the inner Mitochondrial membrane which are then oxidised back to the NAD and FAD forms by accepting their hydrogens by either complex 1 or complex 2. Now the cyanide blocks the electron transport chain which means there's noone to accept those hydrogens. So there will be enormous NADH and FADH in cell, but there will be reduced or nil NAD and FAD. This will lead to disappearance of hydrogen ion acceptors which are essential to carry out Kreb's Cycle and glycolysis. So this will lead to stoppage of them.