Explain how the immunity of a person is affected if there is atrophy (degeneration) of the thymus gland at an early stage of life.
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Solution and Explanation
Step 1: The thymus gland is a primary lymphoid organ responsible for the maturation of T-lymphocytes (T-cells), which play a central role in cell-mediated immunity.
Step 2: If thymus undergoes atrophy at an early stage of life, it results in reduced T-cell production.
Step 3: This weakens the body's immune response, making the person more susceptible to infections and immune-related disorders.
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Student to attempt either option (A) or (B):
(A) Explain how the immunity of a person is affected if there is atrophy (degeneration) of the thymus gland at an early stage of life.
OR
(B) (i) What are interferons? Explain their role in providing immunity to a person.
(ii) Which category of innate immunity defence barrier can interferons be classified into?- CBSE CLASS XII - 2025
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Read the following passage and answer the questions that follow.
Deaths related to the use of drugs were estimated at about 5,00,000 in 2019, 17.5 percent more than in 2009. Liver diseases attributed to Hepatitis B are a major cause of drug-related deaths, according to UNODC, accounting for more than half of the total number of deaths attributed to the use of drugs. Drug overdoses account for a quarter of drug-related deaths.
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OR
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- CBSE CLASS XII - 2025
- Biology
- human health and disease
- (i)What are interferons? Explain their role in providing immunity to a person.
(ii) Which category of innate immunity defence barrier can interferons be classified into?- CBSE CLASS XII - 2025
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