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

According to the chemiosmotic coupling hypothesis,$ATP$ is synthesized in oxidative phosphorylation because:

In the $ETS$ (Electron Transport System),the final electron acceptor is .......

$A$ : In cellular respiration,$ETS$ electron movement is a downhill journey.
$R$ : Electrons move from high redox potential to low redox potential.

Cytochromes are defined as:

What is produced at the end of oxidative phosphorylation where oxidation and phosphorylation occur simultaneously?