Hormones in the Male and Female Reproductive Systems

Male Reproductive System - Effects of Testosterone

• Based on notes on the bottom of page five.
• Primary Sexual Effects of Testosterone: Maturation and enlargement of reproductive organs during development and puberty.
• Sperm development.
• Secondary Sexual Effects of Testosterone:
  • Hair on the face and body.
  • Larger muscles.
  • Wider shoulders.
  • Narrow hips compared to females (though not in all cases; a general tendency).
  • Deeper voice.
  • Increased sex drive.
  • Body shape tends to be triangular.

Female Reproductive System - Effects of Estrogen and Progesterone

• Primary Sexual Effects:
  • Stimulates the growth of the uterus, ovary, and vagina during development.
  • Preparation of the uterine lining (endometrium) for the implantation of a fertilized egg.
• Secondary Sexual Effects:
  • Wider hips.
  • Breast development.
  • Distribution of body hair and fat tissue.
  • Role in attracting mates and contributing to reproductive success.
  • Insulation to enhance breeding capabilities.

Control of Sex Hormones

• Control starts with the hypothalamus. The following steps correspond to a process outlined, likely on a separate page.
• Step 1: Hypothalamus
  • The hypothalamus controls the anterior pituitary (front of the pituitary gland).
  • The anterior pituitary releases several hormones, including growth hormone, prolactin, follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyrotropic hormone, and adrenocorticotropic hormone; focus is on FSH and LH.
  • The hypothalamus releases gonadotropin-releasing hormone (GnRH).
  • GnRH stimulates the anterior pituitary gland to release FSH (follicle-stimulating hormone) and LH (luteinizing hormone).
• Step 2: Anterior Pituitary Gland
  • GnRH activates the anterior pituitary, causing the release of FSH and LH.
  • FSH stimulates follicle development.
    • A follicle refers to either an egg or sperm.
    • In females, FSH stimulates the development of the egg in the ovaries (the egg and its support cells).
    • In males, FSH stimulates the development of sperm in the testes.
• Step 3A: Effects of FSH
  • See above.
• Step 3B: Effects of LH
  • In females, LH triggers ovulation and causes the ruptured follicle to become the corpus luteum.
  • In males, LH stimulates testosterone production by targeting the interstitial cells.
  • Illustration:
    • In the ovary: follicle matures, ruptures (releasing the oocyte), and the ruptured follicle, with help from luteinizing hormone, transforms into the corpus luteum.
    • In males: interstitial cells produce testosterone, and seminiferous tubules facilitate sperm production under the influence of follicle-stimulating hormone.

Ovarian and Uterine Cycles

• Understanding graphs depicting the ovarian and uterine cycles.
• Focus on graphs illustrating hormone levels during the ovarian cycle.