Question

Assertion : The first step in TCA cycle is the condensation of pyruvate with oxaloacetic acid and water.
Reason : This reaction is catalysed by enzyme pyruvate synthase.
A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Answer 1

Correct Answer - d
The TCA cycle starts with the condensation of acetyl group with oxaloacetic acid (OAA) and water to yield citric acid. The reaction is catalysed by the enzyme citrate synthetase and a molecule of CoA is released.
Acetyl `CoA + OA A + H_(2)O underset("synthetase")overset("Citrate")(rarr) " Citrate " + CoA`