Question

Briefly describe the role of hormones in follicular and luteal phase of menstrual cycle in female primates.

Hint:

The hormonal regulation of the menstrual cycle ensures the preparation of the female reproductive system for potential pregnancy each month.

Answer 1

The menstrual cycle in female primates is regulated by hormones that fluctuate throughout the cycle. The cycle consists of two main phases: the follicular phase and the luteal phase. Follicular Phase: - The follicular phase starts on the first day of menstruation and lasts until ovulation. - Hormones involved: 1. Follicle-stimulating hormone (FSH): Stimulates the growth of follicles in the ovaries, each containing an egg. 2. Estrogen: Produced by developing follicles, estrogen stimulates the thickening of the uterine lining in preparation for possible pregnancy. 3. Luteinizing hormone (LH): A peak in LH levels triggers ovulation (the release of an egg from a mature follicle). Luteal Phase: - The luteal phase begins after ovulation and lasts until the start of menstruation. - Hormones involved: 1. Progesterone: After ovulation, the ruptured follicle transforms into the corpus luteum, which secretes progesterone. Progesterone helps maintain the thickened uterine lining to support potential implantation of a fertilized egg. 2. Estrogen: Estrogen levels remain elevated in the luteal phase, supporting the actions of progesterone. If pregnancy does not occur, the corpus luteum degenerates, leading to a drop in estrogen and progesterone, triggering menstruation.
Final Answer: In the follicular phase, FSH and estrogen help stimulate follicle growth and uterine lining thickening. In the luteal phase, progesterone and estrogen maintain the uterine lining, preparing for potential pregnancy.