For the existence of nitrogen in its stable molecular form,how many nitrogen atoms are required?

The three boxes in this diagram represent the three major biosynthetic pathways in aerobic respiration. Arrows represent net reactants or products. Arrows numbered $4, 8$ and $12$ can all be

In the presence of a dilute salt solution,the rate of respiration in a respiring tissue:

$A$: Four $ATP$ molecules are produced directly during glycolysis.
$R$: Substrate level phosphorylation occurs at two steps for a glucose broken down in mitochondrial matrix.

Which of these is not a ketone body?

Photosynthesis and respiration are similar because:
$I$. In eukaryotes,both processes occur in specialized organelles.
$II$. $ATP$ synthesis in both is explained by the chemiosmotic theory.
$III$. Both use an $ETC$ (Electron Transport Chain).
Select the correct option.