......... is required for both respiration and photosynthesis processes.

The following is a scheme showing the electron transport system. Identify the electron carrier molecules indicated as $A$ and $B$. Choose the correct option.

Cytochrome is related to

Which of the following is important in the electron transport system?

The last or terminal cytochrome in the respiratory chain is

Match the electron carriers and reduced substances in Column $I$ with respiratory complexes in Column $II$. Choose the correct option given below.

Column $I$	Column $II$
$i.$ $FADH_2$	$a.$ Complex $III$
$ii.$ Ubiquinol	$b.$ Complex $IV$
$iii.$ $NADH + H^{+}$	$c.$ Complex $II$
$iv.$ Cytochrome $C$	$d.$ Complex $I$