The organelle involved in lipid metabolism and detoxification is: MCQ with Answer and Explanation

Explanation:
Oxytocin stimulates uterine smooth muscle contractions during childbirth and milk ejection during lactation. Thyroxine regulates metabolism; calcitonin and parathyroid hormone control blood calcium. Insulin lowers blood glucose. Adrenaline increases heart rate, not decreases. This question tests the core functions of major hormones.

Explanation:
Vitamin C, chemically ascorbic acid, is a water-soluble vitamin essential for collagen synthesis, wound healing, iron absorption, and antioxidant function. Its deficiency causes scurvy (bleeding gums, weakness). Vitamin A is retinol, B₁ is thiamine, D is calciferol. Vitamin C is abundant in citrus fruits, guava, amla. It is heat-labile and easily destroyed by cooking.

Explanation:
Double fertilization in angiosperms was discovered by the Russian botanist Sergei Nawaschin in 1898 in Lilium and Fritillaria. One male gamete fuses with the egg to form the zygote, the other with the secondary nucleus to form the triploid endosperm. Strasburger discovered fertilization in flowering plants, Amici observed pollen tube, Hofmeister studied alternation of generations.