Thymus

Definition

The thymus is a small gland located in the upper chest, behind the sternum. It plays a crucial role in the development and maturation of T-lymphocytes (T cells), which are essential for the adaptive immune system.

5 Must Know Facts For Your Next Test

1. The thymus is most active during childhood and gradually decreases in size and activity after puberty.
2. Thymosin, a hormone produced by the thymus, is vital for T cell differentiation and function.
3. Nutritional deficiencies, particularly in zinc and vitamin A, can impair thymus function and subsequently weaken immune response.
4. The health of the thymus indirectly affects hematologic health by influencing T cell-mediated immunity.
5. Stress and chronic illness can accelerate thymic involution (shrinkage), compromising immune defense mechanisms.

Review Questions

• What role does the thymus play in the immune system?
• How does nutrition impact the function of the thymus?
• Why is thymic activity more prominent during childhood?

Related terms

Hematopoiesis: The process of forming new blood cellular components.

T-Lymphocytes: A type of white blood cell that matures in the thymus and is essential for adaptive immunity.

Thymosin: A hormone produced by the thymus that promotes T cell development.