Immunity & Cancer
Read the following passage carefully and answer the given questions.
If the pathogens succeed in gaining entry to our body, specific antibodies and cells serve to kill these pathogens. The B-lymphocytes produce an army of proteins in response to pathogens into our blood to fight with them. The T-cells themselves do not secrete antibodies but help B cells to produce them. The principle of immunisation or vaccination is based on the property of ‘memory’ of the immune system. 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 exaggerated response of the immune system to certain antigens present in the environment is called allergy. The human immune system consists of lymphoid organs, tissues, cells and soluble molecules like antibodies. Cancer causing viruses called oncogenic viruses have genes called viral oncogenes. Furthermore, several genes called cellular oncogenes (c-onc) or proto oncogenes have been identified in normal cells which, when activated under certain conditions, could lead to oncogenic transformation of the cells.
The injection which is given to the patients containing preformed antibodies against the snake venom is a type of:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Passive immunisation
In active immunity the body makes its own antibodies after meeting an antigen. This is slow. In passive immunity ready-made antibodies are given directly. This works at once.
(1) Passive immunisation — Correct. Snake venom acts very fast, and there is no time for the body to make its own antibodies. So preformed antibodies against the venom are injected.
(2) Active immunisation — Incorrect. Active immunisation gives an antigen (a vaccine) so that the body makes its own antibodies. That takes time, and no antigen is given here.
(3) Innate immunisation — Incorrect. Innate immunity is the non-specific defence present from birth, such as the skin and phagocytes. It is not given by an injection.
(4) Auto-immunisation — Incorrect. This is not a type of immunisation. Autoimmunity is a disease in which the body attacks its own cells, as in rheumatoid arthritis.
Note: This passage is taken from NCERT as it is. 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 – “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.”