Assertion (A): Saliva contains the enzyme amylase. Reason (R): Amylase begins the digestion of starch in the mouth. MCQ with Answer and Explanation

Explanation:
Vitamin A (retinol) is crucial for the synthesis of rhodopsin, maintaining normal vision, especially in dim light. Vitamin D deficiency impairs calcium absorption, leading to rickets in children. Vitamin C (ascorbic acid) is a water-soluble vitamin, not fat-soluble; vitamins A, D, E, and K are fat-soluble. Thus, statements 1 and 3 are correct.

Explanation:
Pancreatic lipase is the major enzyme for fat digestion, secreted by the exocrine pancreas into the duodenum. It hydrolyzes triglycerides into monoglycerides and free fatty acids, aided by bile salts that emulsify fats. Gastric lipase (stomach) plays a minor role. Liver produces bile but not lipase. Salivary glands produce salivary amylase.

Explanation:
Iodine is a key constituent of the thyroid hormones thyroxine (T₄) and triiodothyronine (T₃). Deficiency leads to goiter and hypothyroidism. Iron is for hemoglobin, calcium for bones, zinc for enzyme function. Iodized salt is a public health measure to ensure adequate iodine intake.