The substance which is essential for both respiration and photosynthesis is:

Cytochrome oxidase contains which of the following elements?

Given below are two statements.
Statement-$I$: During aerobic respiration,$ETS$ regenerates co-enzymes such as $NAD^+$ and $FAD^+$ from their reduced forms $NADH + H^+$ and $FADH_2$.
Statement-$II$: During aerobic respiration,$ETS$ generates a major amount of energy in the form of $ATP$ molecules.
In the light of the above statements,choose the correct answer from the options given below.

Which of the following is not an electron transferring molecule?

Cyanide kills an animal by

The mechanism of $ATP$ production in aerobic respiration was proposed by whom?