AP BIOLOGY

Detailed explanation-1: -They are produced during the Krebs cycle. These molecules are capable of further producing ATP molecules by transfer of electrons and with the enzyme ATP synthase. One NADH molecule produces 3 ATP molecules. Whereas one FADH2 molecule produces 2 ATP molecules.

Detailed explanation-2: -A total of four CO2, six NADHs, two FADH2, and two ATPs are made through the citric acid cycle. NADH and FADH2 are electron carriers that can produce more ATPs later in aerobic respiration.

Detailed explanation-3: -Assertion :Oxidation of one molecule of NADH gives rise to 3 molecules of ATP and that of one molecule of FADH2 produces 2 molecules of ATP. Reason: The number of ATP molecules synthesised depends on the nature of the electron donor.

Detailed explanation-4: -The oxidation of one molecule of NADH thus leads to the synthesis of three molecules of ATP, whereas the oxidation of FADH2, which enters the electron transport chain at complex II, yields only two ATP molecules.

Detailed explanation-5: -Reaction to Transition: 2 NADH generates 6 ATP. The cycle of citric acid: By oxidative phosphorylation, 6 NADH generates 18 ATP. One molecule of NADH is equivalent to two ATP in the cytoplasm. One NADH molecule is equivalent to three ATP molecules inside the mitochondria.