FNH 161 - Male Reproduction System

The reproductive system’s role in homeostasis is_________.

perpetuation of species and union of genetic material.

The primary reproductive organs (gonads) are______. Their primary functions are_____.

Testes in males and ovaries in females. Their primary functions are the production of gametes (sperm and ova) and hormones (testosterone, estrogen, and progesterone).

The ________ is a system of specialized _____ that transports or house gametes.

Reproductive Tract; Ducts

Accessory sex glands provide _______ for reproduction.

supportive secretions

The ______ are the visible portions of the reproductive system.

External Genitalia

Both the Male and Female reproductive systems include:

• Primary Organs (gonads)

• Reproductive tract

• Accessory glands

• External Genitalia

• Secondary sexual characteristics

The key organs in the Male Reproductive System are:

• Testes

• Male Reproductive Tract

  • Epididymis, Vas Deferens, Ejaculatory Duct, Urethra

• Accessory Glands

  • Seminal vesicles, prostate gland, bulbourethral glands

• Penis

List the two key functions of Testes and where they occur.

1. Spermatogenesis occurs in the Sertoli Cells.

2. Testosterone is produced by the Leydig Cells.

Describe the role of Testosterone.

• Before birth, testosterone masculinizes the reproductive tract and promotes descent of testes.

• There is a pause in production from birth until puberty.

• From puberty, testosterone stimulates:

  • Secondary sexual characteristics

  • Sex Drive

  • Production of sperm

  • Growth of bone and lean tissue.

Describe Endocrine control of Testicular function.

• The hypothalamus releases GRH

• This stimulates the Anterior Pituitary to release LH and FSH.

• FSH stimulates spermatogenesis, and LH stimulates testosterone release.

• Testosterone inhibits FSH, LH, and GRH in a negative feedback loop.

Describe the general process of spermatogenesis.

1. Mitotic proliferation - diploid daughter cells divide into identical cells (spermatocytes)

2. Meiosis - Spermatocytes (diploid) divide into spermatids (haploid)

3. Spermiogenesis - formation of head and tail of sperm.

Describe the anatomy of a spermatozoon.

• Head: contains DNA

• Acrosome: Enzyme filled vesicle to penetrate ovum

• Midpiece: contains Mitochondria

• Tail (flagellum): provides mobility

Describe the route of sperm through the reproductive tract.

• Sperm travels from the testes to the Epididymis to mature.

• In ejaculation, the sperm enter the Vas Deferens and converges in the urethra.

• Seminal vesicles provide fluid (semen) for transport.

• Prostate gland contribute to fluidity of sperm

• Bulbourethral glands release lubricating mucus.

Describe the process of erection and ejaculation.

• Erection is a parasympathetic relfex

  • Vasodilation causes enlargement and hardening of penis

• Ejaculation is a sympathetic relfex.

  • Emission: sphincter is closed and contraction moves semen into urethra

  • Expulsion: contraction of muscle and expusion of semen.