Question

Chemically, an antibody is a –
A. Protein
B. Lipoprotein
C. Lipid
D. Nucleoprotein

Answer 1

Hint: The antibody is a Y-shaped molecule composed of four chains. Two of the chains are longer chains and tow chains are short chains. The uppermost part of the molecule interacts with a molecule known as “antigen”. Antigens are specific to the antibodies they bind to. Antibodies are released by Plasma Cells and are used to fight against the foreign potentially harmful pathogens or viruses.

Complete answer:
-An Antibody is a Y-shaped protein, also known as’ Immunoglobulin’ (Ig).Antibodies are secreted by B-cells also called plasma cells and they are used to bind to the specific antigen of a virus or a pathogen to neutralize their effect. Antibodies are made by our body to fight the foreign agent who is potentially harmful to us or might cause any type of disease. Antibodies are made of two large amino acid chains and two small amino acid chains.
-These chains differ at the topmost end of the Y-shaped antibody and this slight change is responsible for the existence of a variety of antibodies in our body, ready to bind a whole variety of potential pathogens.
The part of the antibody that interacts with the part of antigen (an antigen is specific to an antibody and is a part of the foreign particle such as a virus or a pathogen) is called Hypervariable Region.
-Antibodies are released by our immune system to fight off a foreign disease. Antigens are molecules that are bound to the surface of a pathogen and they can interact with their specific antibody. The interaction of antigens to the antibody can bring an immune response in the body to alert that a foreign particle has entered inside.
-Antigen and antibody react just like a Lock and Key. An antigen can bind to its specific antibody only.
The part of the antibody that binds with antigen is called “paratope” and part of antigen binding to the antibody is called “epitope”.

Hence, the correct answer is option (A).

Note: Antibodies are proteins that are found in the blood or body fluid of an organism. They are synthesized by the body as a response to the entry of a foreign particle, known as ‘Antigen”. Antigens are molecules that are bound to the surface of the foreign molecule. They interact with the cells of our body to destroy them. Antibodies are globular plasma proteins.