The scientist who discovered the enzyme reverse transcriptase was: MCQ with Answer and Explanation

Explanation:
Vitamin A (Retinol) is essential for the formation of rhodopsin (visual purple), a pigment in the rod cells of the retina necessary for vision in low light conditions. Deficiency of Vitamin A leads to night blindness (nyctalopia), where a person has difficulty seeing in dim light. Severe deficiency can also cause xerophthalmia and complete blindness.

Explanation:
The Haldane effect describes how the oxygenation of blood in the lungs displaces carbon dioxide from hemoglobin, increasing the removal of CO2. Conversely, deoxygenated blood in the tissues has an increased capacity to carry CO2. This is complementary to the Bohr effect. Exam tip: Bohr = CO2 affects O2; Haldane = O2 affects CO2.

Explanation:
Azotobacter is a free-living, aerobic, nitrogen-fixing soil bacterium used as a biofertilizer for non-legume crops like wheat, maize, and cotton. Rhizobium is symbiotic, Nostoc is a cyanobacterium (algal biofertilizer), and mycorrhiza is a fungal symbiont that enhances phosphorus uptake. Biofertilizers reduce the need for chemical nitrogen fertilizers and are eco-friendly.