Human health and disease
Read the following passage carefully and answer the given questions.
Diseases like typhoid, cholera, pneumonia, fungal infections of skin, malaria and many others are a major cause of distress to human beings. Our immune system plays the major role in preventing these diseases when we are exposed to disease-causing agents. If the pathogens succeed in gaining entry to our body, specific antibodies and cells serve to kill these pathogens. AIDS and cancer kill a large number of individuals worldwide. AIDS is fatal but can be prevented if certain precautions are taken. Many cancers are curable if detected early and appropriate therapeutic measures are taken. Drug and alcohol abuse among youth and adolescents is becoming another cause of concern.
Which one of the followings is not an antibody produced in our body?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Ig B
An antibody (immunoglobulin) is a protein made by B-lymphocytes against an antigen. Different types are produced in our body: IgA, IgM, IgE and IgG.
(1) Ig A — An antibody produced in our body. It is the antibody in colostrum, the first milk of a mother.
(2) Ig M — An antibody produced in our body.
(3) Ig E — An antibody produced in our body. It is the type involved in allergic reactions.
(4) Ig B — Not an antibody produced in our body. There is no antibody of this name. The four types are IgA, IgM, IgE and IgG.
Note: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.
NCERT Extract:
Acquired Immunity – “… The B-lymphocytes produce an army of proteins in response to pathogens into our blood to fight with them. These proteins are called antibodies. The T-cells themselves do not secrete antibodies but help B cells to produce them. Each antibody molecule has four peptide chains, two small called light chains and two longer called heavy chains. Hence, an antibody is represented as H2L2. Different types of antibodies are produced in our body. IgA, IgM, IgE, IgG are some of them.”