Which of the following diseases is caused by a deficiency of insulin? MCQ with Answer and Explanation

Explanation:
Not all bacteria cause disease; many are beneficial (e.g., nitrogen fixers, gut flora). The other statements are true.

Explanation:
Klinefelter syndrome (47,XXY) is a sex chromosome aneuploidy causing male hypogonadism, tall stature, gynecomastia, and infertility. Turner syndrome (45,X) affects females. Down syndrome is trisomy 21. Cri du chat is deletion in chromosome 5. Nondisjunction during meiosis leads to these aneuploidies.

Explanation:
Fats yield about 9 kcal/g of energy, more than double the 4 kcal/g provided by carbohydrates and proteins. Roughage (dietary fiber) adds bulk to the stool and stimulates peristalsis, preventing constipation. Water is an essential nutrient, crucial for hydration, solvent functions, and temperature regulation, though it provides no calories. Thus, statements 1 and 2 are correct.