Males And Females Reproductive Hormones and Characteristics

Reproductive Hormones

Gonadotropin-Releasing Hormone (GnRH)

  • Definition: GnRH is a hormone produced and released by the hypothalamus.

  • Function: It controls the release of two key hormones: Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH).

Follicle Stimulating Hormone (FSH)

  • Source: Produced by the action of GnRH.

  • Role in Females:

    • Acts on the ovaries.

    • Stimulates the growth and development of ovarian follicles.

  • Role in Males:

    • Acts on Sertoli cells.

    • Stimulates the production of sperm cells.

Luteinizing Hormone (LH)

  • Role in Females:

    • Acts on ovarian follicles.

    • Triggers ovulation.

    • Promotes the formation of luteal cells that develop into the Corpus Luteum (CL).

  • Role in Males:

    • Acts on Leydig cells.

    • Stimulates the production of testosterone.

Progesterone

  • Definition: A steroid hormone produced by the Corpus Luteum (CL).

  • Function:

    • Provides the body with time to prepare for pregnancy.

    • Essential for maintaining pregnancy.

Estrogen

  • Definition: Traits that develop at puberty that are not directly involved in reproduction but are influenced by sex hormones.

  • Behavior During Estrus (Heat):

    • Responsible for sexual behavior, seen in both males and females.

    • The mechanisms in males are not fully understood.

Prostaglandin F2α (PGF2α)

  • Definition: A lipid hormone produced by the uterus in females.

  • Functions:

    • Causes regression of the Corpus Luteum if no pregnancy occurs.

    • Induces contractions of the uterus to expel the contents when pregnancy does occur.

Testosterone

  • Source: Produced by Leydig cells.

  • Functions:

    • Promotes secondary sex characteristics in males.

    • Influences male sex behavior.

Oxytocin

  • Source: Produced by the hypothalamus and stored in the posterior pituitary gland.

  • Functions:

    • Induces milk production in lactating females.

    • Facilitates placental expulsion following childbirth.

    • May also be produced in Leydig cells in some species.