Lymphatic capillaries are more permeable than blood capillaries due to:

Correct Answer: B

Rationale: Overlapping endothelial cells allow greater permeability in lymphatic capillaries; they have thinner walls , looser junctions , and no smooth muscle .

Correct Answer: B

Rationale: Macrophages in red pulp phagocytose RBCs; lymphocytes , T , and B cells are in white pulp.

Correct Answer: C

Rationale: Trunks drain lymph into ducts; filtering is nodes, collecting is capillaries, producing is marrow.

Correct Answer: B

Rationale: The thymus matures T cells ; B cells mature in bone marrow, macrophages and neutrophils are innate.

Correct Answer: C

Rationale: Neutrophils are rapid innate responders; T and B cells are adaptive, dendritic cells present antigens.