Question

Which lymphoid organ is particularly large in children but gradually shrinks with age?

Options

• Spleen

• Bone marrow

• Thymus

• Lymph nodes

Answer 1

The thymus is a primary lymphoid organ that is proportionally largest and most active during childhood when T-lymphocyte production is at its peak. As an individual ages, thymic tissue is gradually replaced by fatty tissue, and the thymus shrinks (a process called thymic involution), reflecting the declining need for new T-cell production in older adults.