Consider statements about ecology: 1. An ecosystem includes living and non-living components. 2. A community includes only one species. 3. A population includes individuals of the same species. Which are correct? MCQ with Answer and Explanation

Explanation:
Chlorophyll, the primary photosynthetic pigment, is embedded in the thylakoid membranes within chloroplasts. These membranes contain photosystems I and II, where light-dependent reactions occur. The stroma of the chloroplast houses the Calvin cycle enzymes. Chlorophyll absorbs mainly blue and red light, reflecting green, giving leaves their color.

Explanation:
Progesterone is the primary hormone of the luteal phase (also called the secretory phase) of the menstrual cycle. After ovulation, the ruptured Graafian follicle transforms into the corpus luteum, which secretes large amounts of progesterone. Progesterone prepares and maintains the uterine endometrium (thickening it, increasing blood supply, and stimulating glandular secretion) for the potential implantation of a fertilized egg. If pregnancy does not occur, the corpus luteum degenerates, progesterone levels drop, and menstruation begins.

Explanation:
Hugo de Vries proposed the mutation theory in 1901 based on his experiments with evening primrose (Oenothera lamarckiana), suggesting that new species arise suddenly through large mutations. Darwin proposed gradual natural selection, Lamarck use-disuse, Wallace independently natural selection.