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.
In which of the following examples, pre-formed antibodies are not introduced into our body?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Diabetes
Note 1: The given answer is as per the official NTA Answer Key. However, the question can have more than one correct answer, i.e. both Option (2) and Option (3), because in polio the body is given a vaccine and makes its own antibodies, and in diabetes no antibodies are given at all, as explained below.
Pre-formed antibodies are ready-made antibodies that are injected directly into the body. This gives passive immunity. It is used when the body must be protected quickly and cannot wait to make antibodies. A vaccine works differently. It contains antigens of the pathogen, and the body itself makes the antibodies. This is active immunity.
(1) Tetanus — Pre-formed antibodies are introduced. In a case of tetanus, the pre-formed antibodies, or antitoxin, are injected directly.
(2) Polio — Pre-formed antibodies are not introduced (also correct). Polio is controlled by vaccines. A vaccine carries a weakened or inactivated pathogen, so the body makes its own antibodies. No pre-formed antibodies are introduced.
(3) Diabetes — Pre-formed antibodies are not introduced. This is the answer given by NTA. Diabetes is not an infection and has no antibody treatment. It is managed by taking insulin, so no pre-formed antibodies are introduced.
(4) Anti-snake venom injections for snakebites — Pre-formed antibodies are introduced. The injection given to the patient contains pre-formed antibodies against the snake venom.
Note 2: 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:
Vaccination and Immunisation – “In vaccination, a preparation of antigenic proteins of pathogen or inactivated/weakened pathogen (vaccine) are introduced into the body. The antibodies produced in the body against these antigens would neutralise the pathogenic agents during actual infection. The vaccines also generate memory – B and T-cells that recognise the pathogen quickly on subsequent exposure and overwhelm the invaders with a massive production of antibodies. If a person is infected with some deadly microbes to which quick immune response is required as in tetanus, we need to directly inject the preformed antibodies, or antitoxin (a preparation containing antibodies to the toxin). Even in cases of snakebites, the injection which is given to the patients, contain preformed antibodies against the snake venom. This type of immunisation is called passive immunisation.”
Genetically Engineered Insulin – “… Management of adult-onset diabetes is possible by taking insulin at regular time intervals.”