In the process of blood clotting, the enzyme 'thrombin' is formed from its inactive precursor 'prothrombin' in the presence of: MCQ with Answer and Explanation

Explanation:
ELISA (enzyme-linked immunosorbent assay) uses enzyme-linked antibodies to detect and quantify specific antigens or antibodies in a sample. PCR amplifies DNA, Northern blotting detects RNA, Southern blotting DNA.

Explanation:
Active immunity occurs when the body's own immune system is stimulated by an antigen (either through infection or vaccination) to produce its own antibodies and memory cells, providing long-lasting protection. Passive immunity occurs when an individual is directly given pre-formed antibodies (like through mother's milk or antiserum), providing immediate but temporary protection. Vaccination stimulates the body to produce its own immune response, thus providing artificial active immunity, not passive. Thus, statements 1 and 2 are correct.

Explanation:
Acromegaly is the enlargement of bones and soft tissues due to overproduction of growth hormone in adults after growth plates have fused. Gigantism occurs in childhood, dwarfism GH deficiency, cretinism congenital hypothyroidism.