What is the term for immunity from prior exposure?

Correct Answer: A

Rationale: Natural active is from prior exposure; artificial active is vaccines, passive (C, D) is antibody transfer.

Correct Answer: B

Rationale: Lymphatic capillaries remove fat and bacteria due to gaps in endothelium and interrupted basal lamina, not tight junctions or non-fenestrated cells.

Correct Answer: A

Rationale: Carcinoma causes lymph node enlargement via metastatic spread from a primary site.

Correct Answer: D

Rationale: Palatine tonsils have non-keratinized epithelium , glands opening into crypts , and nodules ; they are non-capsulated but prone to inflammation (D is incorrect).

Correct Answer: C

Rationale: T-lymphocytes enter lymph nodes via post-capillary venules ; figure context suggests lymph node, not tonsil , spleen , or efferent entry .