The double helix model of DNA was given by: MCQ with Answer and Explanation

Explanation:
Malnutrition includes undernutrition (deficiency of calories, protein, or micronutrients) and overnutrition (excess intake leading to obesity and related diseases). Both result in physiological disorders. Examples: marasmus and kwashiorkor (deficiency), obesity (excess). A balanced diet prevents malnutrition. It is a significant global health issue, especially in developing countries.

Explanation:
The plasma membrane (cell membrane) is primarily composed of a phospholipid bilayer with embedded proteins, following the fluid mosaic model, regulating transport in and out of the cell. The nucleus is the membrane-bound organelle that houses the cell's genetic material (DNA) organized into chromosomes. Mitochondria are the site of aerobic cellular respiration and ATP production; chloroplasts are the organelles where photosynthesis occurs in plant cells. Thus, statements 1 and 2 are correct.

Explanation:
A typical leaf consists of the leaf base, petiole (stalk), and lamina (leaf blade). In dicotyledonous leaves, stomata are generally more abundant on the lower epidermis to reduce excessive water loss from direct sunlight, unlike monocots where they may be equal. Therefore, statements 1 and 3 are correct, while statement 2 is incorrect.