Which of the following statements are correct regarding immunity?
(I) Innate immunity is achieved through various types of barriers.
(II) Acquired immunity is present from birth and inherited from parents.
(III) Acquired immunity can be categorised into antibody-mediated and cell-mediated immunity.
(IV) Innate immunity is also known as specific immunity.
(V) Acquired immunity involves specialised cells (T-cells and B-cells) and circulating antibodies.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → I, III and V
Innate immunity is a non-specific defence present at birth, given by four types of barriers. Acquired immunity is pathogen specific, has memory, and is carried out by B-lymphocytes (through antibodies) and T-lymphocytes (through cell-mediated immunity).
(I) Innate immunity is achieved through various types of barriers. — True. It is given by four types of barriers: physical, physiological, cellular and cytokine barriers.
(II) Acquired immunity is present from birth and inherited from parents. — False. It is innate immunity that is present at the time of birth. Acquired immunity develops after the body meets a pathogen.
(III) Acquired immunity can be categorised into antibody-mediated and cell-mediated immunity. — True. The humoral (antibody-mediated) response and the cell-mediated immune response (CMI) are the two types of acquired immune response.
(IV) Innate immunity is also known as specific immunity. — False. Innate immunity is a non-specific type of defence. It is acquired immunity that is pathogen specific.
(V) Acquired immunity involves specialised cells (T-cells and B-cells) and circulating antibodies. — True. B-lymphocytes produce antibodies into the blood, and T-lymphocytes help B cells and mediate CMI.
NCERT Extract:
Innate Immunity – “Innate immunity is non-specific type of defence, that is present at the time of birth. This is accomplished by providing different types of barriers to the entry of the foreign agents into our body.”
Acquired Immunity – “Acquired immunity, on the other hand is pathogen specific. … The primary and secondary immune responses are carried out with the help of two special types of lymphocytes present in our blood, i.e., B-lymphocytes and T-lymphocytes. … Because these antibodies are found in the blood, the response is also called as humoral immune response. This is one of the two types of our acquired immune response – antibody mediated. The second type is called cell-mediated immune response or cell-mediated immunity (CMI).”