The enzyme in saliva that begins starch digestion is: MCQ with Answer and Explanation

Explanation:
Vitamin A is a fat-soluble vitamin stored primarily in the liver, and excess can lead to toxicity. The B-complex vitamins are water-soluble and generally not stored in the body in significant amounts. Fat-soluble vitamins (A, D, E, K) are stored in body fat and liver, making excess Vitamin D difficult to excrete, potentially causing hypervitaminosis D. Thus, statements 1 and 2 are correct.

Explanation:
Oxytocin from the posterior pituitary causes myoepithelial cells around mammary alveoli to contract, ejecting milk. Prolactin stimulates milk synthesis.

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.