The 'Red Data Book' keeps records of: MCQ with Answer and Explanation

Explanation:
The skin and mucous membranes form the first line of defense (innate immunity), acting as physical barriers that prevent pathogens from entering the body. White blood cells (leukocytes), including phagocytes and lymphocytes, are the cellular components of the immune system that identify, attack, and destroy pathogens. Antibiotics are drugs designed to kill or inhibit the growth of bacteria; they are completely ineffective against viruses, which lack the cellular machinery targeted by antibiotics. Thus, statements 1 and 2 are correct.

Explanation:
Iron-deficiency anemia is the most prevalent nutritional deficiency worldwide, characterized by fatigue, pallor, and reduced oxygen-carrying capacity. It is treated with iron supplementation and dietary changes.

Explanation:
ADH (vasopressin) increases water permeability of the collecting duct cells by inserting aquaporins, reducing urine volume. Aldosterone increases sodium reabsorption, renin is an enzyme, ANP promotes sodium excretion.