Question

In Krebs cycle :

• A. ADP is converted into ATP
• B. pyruvic acid is converted into $C{{O}_{2}}$ and ${{H}_{2}}O$
• C. glucose is converted into $C{{O}_{2}}$
• D. pyruvic acid is converted into ATP

Answer 1

Answer: (B)

pyruvic acid is converted into $C{{O}_{2}}$ and ${{H}_{2}}O$

Answer 2

In the presence of oxygen the oxidation of glucose that begins in glycolysis continues, where glycolysis leaves off with pyruvate. The cell harvests pyruvates considerable energy in two steps : first by oxidising pyruvate to form acetyl Co-A and then by oxidising acetyl Co-A in the Krebs cycle. The reactions of Krebs cycle occur in mitochondria. In this cycle the two carbon acetyl Co-A combines with a 4-carbon molecule called oxaloacetate. The resulting 6 C molecule goes through a sequence of electron yielding oxidation reaction to form $C{{O}_{2}}$ and wafer with releasing sufficient energy. The NADH and $FAD{{H}_{2}}$ formed during Krebs cycle carry energetic electrons and are employed to drive the synthesis of large amount of ATP by electron transport chain.