Certain vitamin $B$ acts as

Carboxypeptidase requires $........$ for its activity.

If organic compounds are loosely bound to the apoenzyme,what are they called?

Assertion : $A$ co-enzyme or metal ion that is very tightly bound to enzyme protein is called a prosthetic group.
Reason : $A$ complete,catalytically active enzyme together with its bound prosthetic group is called an apoenzyme.

Substances which enhance reactions after combining with enzymes are called

By what other name is a prosthetic group known?