Vaccination provides which type of immunity? MCQ with Answer and Explanation

Explanation:
Thiamine pyrophosphate (TPP), derived from vitamin B₁, is a cofactor for pyruvate dehydrogenase, which catalyzes the oxidative decarboxylation of pyruvate to acetyl-CoA. Riboflavin is FAD, niacin is NAD, pyridoxine PLP for transamination.

Explanation:
Robert Hooke observed thin slices of cork under a microscope he designed and saw honeycomb-like compartments which he termed 'cells' in his 1665 book 'Micrographia'. Leeuwenhoek discovered living cells (bacteria, protozoa). Brown discovered the nucleus (1831), and Virchow proposed that all cells arise from pre-existing cells (1855). Hooke's cells were dead, empty cell walls of cork.

Explanation:
The holotype is the single physical specimen designated by the original author when the species is first formally described. It serves as the ultimate reference point for that species name. An isotype is a duplicate of the holotype, syntypes are multiple specimens cited when no holotype was designated, and paratypes are additional specimens cited in the original description.