Statement - I: The number of ATP molecules produced in ETS depends on nature of electron donor.
Statement - II: Oxidation of one molecule of matrix  $\mathrm{NADH}+{\mathrm{H}}^{+}$ yield 3 ATP whereas ${\mathrm{FADH}}_2$ yield 2 ATP.

The number of ATP molecules synthesised depends on the nature of the electron donor. Oxidation of one molecule of NADH gives rise to 3 molecules of ATP, while that of one molecule of FADH2 produces 2molecules of ATP.