Consider statements about vitamins: 1. Vitamin E acts as an antioxidant. 2. Vitamin K is synthesized by gut bacteria. 3. Vitamin C is essential for collagen synthesis. Which are correct? MCQ with Answer and Explanation

Explanation:
Alexander Fleming, a Scottish bacteriologist, discovered penicillin in 1928. He returned from a vacation to find that a Petri dish containing Staphylococcus bacteria had been accidentally contaminated by a mold. He noticed a clear zone around the mold where the bacteria had been killed. The mold was identified as Penicillium notatum, and the antibacterial substance was named penicillin.

Explanation:
Louis Pasteur developed the first rabies vaccine in 1885, using dried spinal cords from infected rabbits. Jenner developed smallpox vaccine, Koch identified tuberculosis bacterium, Salk developed inactivated polio vaccine.

Explanation:
Iron (Fe²⁺) is a central component of the heme group in hemoglobin, enabling oxygen binding. Deficiency leads to iron-deficiency anemia, characterized by fatigue, pallor, and reduced oxygen-carrying capacity. Calcium is for bones and clotting, magnesium is a cofactor and in chlorophyll, potassium is for nerve impulses. Iron is obtained from diet (meat, leafy greens).