The structure of DNA was described as a double helix by: MCQ with Answer and Explanation

Explanation:
FSH, released from the anterior pituitary, stimulates Sertoli cells in the seminiferous tubules to support spermatogenesis (production of sperm). Luteinizing hormone (LH) stimulates Leydig cells to produce testosterone, which is also necessary for spermatogenesis. Estrogen is female hormone, prolactin for milk, oxytocin for uterine contraction.

Explanation:
The pituitary gland controls many other endocrine glands via tropic hormones (TSH, ACTH, FSH, LH). It is regulated by the hypothalamus. Thus, it is often called the master gland.

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.