Question

The correct match between item I and item II is:

	Item I		Item II
(A)	Allosteric effect	(P)	Molecule binding to the active site of enzyme
(B)	Competitive inhibitor	(Q)	Molecule crucial for communication in the body
(C)	Receptor	(R)	Molecule binding to a site other than the active site of enzyme
(D)	Poison	(S)	Molecule binding to the enzyme covalently

• A. $\left(A\right)\to \left(P\right);\left(B\right)\to \left(R\right);\left(C\right)\to \left(S\right);\left(D\right)\to \left(Q\right)$
• B. $\left(A\right)\to \left(R\right);\left(B\right)\to \left(P\right);\left(C\right)\to \left(S\right);\left(D\right)\to \left(Q\right)$
• C. $\left(A\right)\to \left(P\right);\left(B\right)\to \left(R\right);\left(C\right)\to \left(Q\right);\left(D\right)\to \left(S\right)$
• D. $\left(A\right)\to \left(R\right);\left(B\right)\to \left(P\right);\left(C\right)\to \left(Q\right);\left(D\right)\to \left(S\right)$

Answer 1

The correct option is D $\left(A\right)\to \left(R\right);\left(B\right)\to \left(P\right);\left(C\right)\to \left(Q\right);\left(D\right)\to \left(S\right)$

• In biochemistry, allosteric regulation is the regulation of an enzyme by binding an effector molecule at a site other than the enzyme's active site. The site to which the effector binds is termed the allosteric site or regulatory site.

• In competitive inhibition, an inhibitor that resembles the normal substrate binds to the enzyme, usually at the active site, and prevents the substrate from binding.

• A receptor is a protein-molecule that recognizes and responds to endogenous chemical signals.

• A number of poisons are harmful to cells because they are potent noncompetitive inhibitors(These substances, which are generally structurally unrelated to the substrate, bind reversibly to groups distant from the binding site of the enzyme and are thus less specific than competitive inhibitors).

So, the correct answer is '$D$'.