The region of the root that provides protection to the growing tip is the: MCQ with Answer and Explanation

Explanation:
Dengue is a viral disease caused by the Dengue virus, not a protozoan (malaria is caused by a protozoan). Filariasis (elephantiasis) is caused by parasitic nematode worms like Wuchereria bancrofti, which block lymphatic vessels. Pneumonia is an infection that inflames the air sacs in one or both lungs, affecting the respiratory system. Thus, statements 2 and 3 are correct.

Explanation:
Spermiogenesis is the final stage of spermatogenesis, where the spherical, non-motile spermatids undergo a complex morphological transformation to become highly specialized, motile spermatozoa (sperm). This involves the formation of the acrosome, condensation of the nucleus, development of the flagellum (tail), and the shedding of excess cytoplasm. Spermiation is the subsequent release of these mature sperm into the tubule lumen.

Explanation:
The skin and mucous membranes act as primary physical barriers in innate immunity, preventing pathogen entry. Phagocytosis by macrophages and neutrophils is a non-specific (innate) cellular defense mechanism, not a specific immune response. Memory B and T cells are produced during the primary specific immune response and provide rapid, long-lasting immunity upon re-exposure. Thus, statements 1 and 3 are correct.