Class 12th Biology 2011 Set3 Delhi Board Paper Solution
Question 15
Name the two types of immune systems in a human body. Why are cell mediated and humoral immunities so called?
Name the two types of immune systems in a human body. Why are cell mediated and humoral immunities so called?
OR
Write the scientific names of the causal organisms of elephantiasis and ringworm in humans. Mention the body parts affected by them.
Answer
Human being are provided with two type of immune system-
1. Innate immunity
2. Acquired immunity
1. Innate immunity – is the type of immunity which is confer to a baby by birth, and is the primary defense system of our body.
2. Aquired immunity – it is acquired by a person during various stage of a person life, it involves B and T cells.
Humoral immunity is so called because blood is involved in developing defense in the bodys, it is supported by the presence of B cells.
Cell mediate immunity it is so called because of the involvement of different cell for developing immune response, it actively involves T cells.
OR
Elephantiasis is caused by Wuchereria species; it may be either W. bancrofti or W.malayi
Ringworm is caused by genera Microsporum, Trichophyton and Epidermophyton
Filarial worm remain in the body for a long time and develops chronic inflammation. They inhabit lymphatic vessels of lower limbs resulting in the swelling of lower limbs and the disease is called elephantiasis or filariasis. Genital organ also gets affected resulting in deformities in its shape and size. Ringworm fungi may infect any part of the body, leads to dry, scaly lesions. Commonly it inhabit in between fingers.
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