Pyridoxine is the chemical name of: MCQ with Answer and Explanation

Explanation:
Telomerase is a ribonucleoprotein enzyme that adds repetitive nucleotide sequences to the ends of chromosomes (telomeres), preventing them from shortening during DNA replication. It is highly active in germ cells, stem cells, and most cancer cells, granting them replicative immortality. In most normal somatic cells, telomerase is inactive, leading to gradual telomere shortening and cellular aging.

Explanation:
Magnesium (Mg²⁺) is the central atom in the porphyrin ring of chlorophyll, essential for absorbing light energy during photosynthesis. Iron is central in heme (hemoglobin, cytochromes). Calcium is a secondary messenger and structural component, zinc is a cofactor. Magnesium deficiency causes chlorosis.

Explanation:
Penicillin is derived from the fungus Penicillium chrysogenum (formerly P. notatum). Alexander Fleming discovered it in 1928.