Question

Types of drugs that mimic the natural messenger by switching on the receptor are called?
A.Antagonists
B.Chemical messengers
C.Receptors
D.Agonists

Answer 1

Hint:To answer this question, you must be familiar with the action of messengers in the body. The drug should be able to bind to a receptor and activate it to produce a biological response.

Complete step by step answer:
Drugs that enter the living body tend to stimulate receptors, ion channels and act on enzymes causing the body to react to the actions of the drug. Thus various desired reactions can be made to occur in the body by the use of specific drugs.
Drugs are of two different types, namely agonists and antagonists.
Agonists are drugs that activate certain receptors by binding to it just like natural drug messengers.Antagonists as the name suggests prevent the agonists from stimulating the cell receptors.Thus, the types of drugs that mimic the natural messengers by switching on the receptor are agonists.

The correct answer is D.

Note:
Drugs interact with receptors by forming bonds at specific binding sites. Majority of the receptors are composed of proteins and the drugs therefore interact with the amino acids changing the conformation of the receptor proteins.
The bonds formed between receptors and drugs are ionic bonds or hydrogen bonds.
Ionic bonding occurs through attractions between opposite charges, say between a protonated amino and dissociated carboxylic acid group. The bond formed is very strong and can act over large distances.Hydrogen bonding is a small but significant attraction between hydrogen atoms and polar functional groups. They act over short distances only and are dependent on the alignment between the binding functional groups.