Assertion (A): Green plants are called autotrophs. Reason (R): They can synthesize their own food by photosynthesis. MCQ with Answer and Explanation

Explanation:
The Krebs cycle, also known as the citric acid cycle or TCA cycle, is the central metabolic pathway for the oxidation of acetyl-CoA to produce energy (ATP, NADH, FADH2). It was discovered by the British-German biochemist Sir Hans Adolf Krebs in 1937. He was awarded the Nobel Prize in Physiology or Medicine in 1953 for this discovery. Melvin Calvin elucidated the carbon pathway in photosynthesis.

Explanation:
Genetic variation provides the raw material for natural selection. If all individuals were identical, selection could not favor any. R correctly explains A.

Explanation:
Estrogen, secreted by the developing ovarian follicles, promotes the development of female secondary sexual characteristics such as breast development, widening of hips, and distribution of body fat. Testosterone is the male sex hormone. Progesterone prepares the uterus for pregnancy, and prolactin stimulates milk production.