What happens to the thymus after puberty?

• A. It gradually decreases in size and becomes replaced by fat.
• B. It remains the same size and function throughout life.
• C. It is immediately removed from the body.
• D. It increases in size and activity.

Answer: (A)

Verified step by step guidance

1. Understand the role of the thymus: The thymus is a lymphoid organ located in the chest, behind the sternum. It plays a critical role in the development and maturation of T-lymphocytes (T-cells), which are essential for adaptive immunity.
2. Recognize the changes in the thymus over time: The thymus is most active during childhood and adolescence, supporting the immune system's development. After puberty, its activity decreases as the immune system matures.
3. Learn about involution: After puberty, the thymus undergoes a process called involution, where its functional tissue gradually decreases in size and is replaced by adipose (fat) tissue. This is a normal physiological change.
4. Clarify misconceptions: The thymus does not remain the same size and function throughout life, nor is it immediately removed from the body. It also does not increase in size and activity after puberty.
5. Conclude the correct answer: The correct answer is that the thymus gradually decreases in size and becomes replaced by fat after puberty, reflecting its reduced role in immune function as the body matures.