Question

Select the correct statement.

• A. FAD is hydrogen acceptor when succinic acid is oxidised to malic acid.
• B. Oxygen acts a terminal electron acceptor in aerobic respiration.
• C. Cytochrome c and a₃ contains two copper centres.
• D. Respiration is a catabolic process only.

Answer 1

Answer: (B)

FAD is a hydrogen acceptor when succinic acid is oxidized to fumaric acid in Kreb's cycle. It is the only step in respiration where FAD is hydrogen acceptor. Respiration is an amphibolic process. Cytochrome c is a mobile carrier between complex 3 and 4 which consists of the only iron center, cytochrome a₃ contains two copper centers.
At the end of the electron transport chain, the 2 electrons, 2 protons (2H+), and (1/2) O₂ (1 atom of oxygen) combine to form one molecule of water. In this way, oxygen is the terminal acceptor of electrons of the respiratory chain.