Which cytokine enhances macrophage activity?

Correct Answer: C

Rationale: IFN-gamma boosts macrophages; IL-2 aids T cells, IL-4 helps B cells, IL-10 suppresses.

Correct Answer: A

Rationale: Lymph typically contains proteins, microorganisms, and macrophages, but red blood cells are primarily in the blood, not lymph, unless there's injury or pathology.

Correct Answer: D

Rationale: Paracortex is rich in T-lymphocytes; primary/secondary follicles and medullary cords contain B-lymphocytes.

Correct Answer: C

Rationale: Blood sinusoids collect blood into venous sinuses in red pulp.

Correct Answer: D

Rationale: Macrophages phagocytose debris , destroy erythrocytes , and contribute to iron metabolism (part of B); all apply.