Marasmus is a disease of severe malnutrition characterized by: MCQ with Answer and Explanation

Explanation:
Coal is a fossil fuel formed over millions of years and is finite, thus non-renewable. Solar, wind, and tidal energy are renewable and replenishable. Non-renewable resources include coal, petroleum, natural gas, and nuclear minerals. Overexploitation leads to depletion and environmental pollution. Conservation of such resources is essential for sustainable development.

Explanation:
Magnesium (Mg²⁺) is the central atom in the porphyrin ring of chlorophyll, essential for absorbing light energy during photosynthesis. Iron is central in heme (hemoglobin, cytochromes). Calcium is a secondary messenger and structural component, zinc is a cofactor. Magnesium deficiency causes chlorosis.

Explanation:
Iodine deficiency impairs thyroid hormone synthesis, leading to elevated TSH and enlargement of the thyroid gland (goiter). Iodized salt prevents it.