Sexual Development of Males and Females

Introduction

• Onset of puberty marks significant changes in the sexual development of both males and females.
• Hypothalamus begins to release pulses of Gonadotropin-Releasing Hormones (GnRH).

Male Sexual Development

• GnRH Release:

  • Constant frequency of GnRH pulses.
  • Acts on the anterior pituitary gland to release:
    • Luteinizing Hormone (LH)
    • Follicle Stimulating Hormone (FSH)

• Effects of LH and FSH:

  • Stimulate testes for:
    • Spermatogenesis (production of sperm cells)
    • Release of testosterone
  • Induce secondary sex characteristics:
    • Growth of body hair
    • Enlargement of the larynx (deepening voice)
    • Broadening of shoulders

• Role of Testosterone:

  • Hormone responsible for secondary sex characteristics.
  • Negative feedback mechanism:
    • Inhibits hypothalamus from releasing GnRH.
    • Inhibits anterior pituitary from releasing FSH and LH.

Female Sexual Development

• GnRH Release:

  • Frequency of pulses varies with menstrual cycle.
  • Acts on the anterior pituitary to release:
    • Luteinizing Hormone (LH)
    • Follicle Stimulating Hormone (FSH)

• Effects of LH and FSH:

  • Stimulate ovaries for:
    • Folliculogenesis (maturation of follicles)
    • Release of estrogen and progesterone

• Secondary Sex Characteristics in Females:

  • Development of body hair
  • Growth of breasts
  • Widening of hips

• Role of Estrogen and Progesterone:

  • Important for menstrual cycle and pregnancy.
  • Negative feedback mechanism:
    • Inhibits release of GnRH from hypothalamus.
    • Inhibits release of FSH and LH from anterior pituitary.
  • More complex due to menstrual cycle variations.

Conclusion

• The release and regulation of these hormones play crucial roles in sexual development and reproductive function for both males and females.
• Future discussions will include more details about the menstrual cycle and hormonal variations in females.