NEET 2012 · Class 11

Biomolecules

For its activity, carboxypeptidase requires

  1. (A)zinc
  2. (B)iron
  3. (C)niacin
  4. (D)copper

The NCERT line that answers it

Verbatim line

A number of enzymes require metal ions for their activity which form coordination bonds with side chains at the active site and at the same time form one or more coordination bonds with the substrate, e.g., zinc is a cofactor for the proteolytic enzyme carboxypeptidase.

Chapter
Biomolecules
Section
9.8.6 Co-factors
Page
14
Words matched
30 of 45

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

0, emb=1.0, combined=1.0). Verified: high — The span explicitly states 'zinc is a cofactor for the proteolytic enzyme carboxypeptidase', which directly answers the MCQ by identifying zinc as the required element for carboxypeptidase activity.

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