Lecture 24: Reproductive System 1 — Male

What are the male primary reproductive organs?

Testes.

What are gonads?

Organs that make gametes and secrete sex hormones.

What gametes do testes produce?

Sperm.

What major sex hormone group is made by testes?

Androgens, especially testosterone.

What are accessory reproductive organs?

Ducts, glands, and external genitalia supporting reproduction.

Why is reproduction essential for a species?

It allows production of offspring.

Where are testes located?

In the scrotum.

What is the scrotum?

A skin-covered sac containing the testes.

Why must testes be kept cooler than core body temperature?

Normal sperm production requires a lower temperature.

Where are sperm produced?

Seminiferous tubules of the testes.

What is the epididymis?

A coiled duct where sperm mature and are stored.

What is the ductus deferens (vas deferens)?

A muscular duct carrying sperm from the epididymis toward the ejaculatory duct.

What is the ejaculatory duct?

A duct that delivers sperm and gland secretions into the urethra.

What is the route of sperm out of the body?

Epididymis → ductus deferens → ejaculatory duct → urethra.

What is the urethra's role in males?

Carries urine and, during ejaculation, semen to the exterior.

What are the three parts of the male urethra?

Prostatic, membranous, and spongy urethra.

Which urethral segment passes through the prostate?

Prostatic urethra.

Which urethral segment runs through the penis?

Spongy urethra.

What are seminal vesicles?

Accessory glands contributing fluid to semen.

What does the prostate contribute?

Fluid that forms part of semen.

What do bulbourethral glands release?

Lubricating mucus before ejaculation.

What is semen?

Sperm mixed with secretions from accessory glands.

What is the function of the penis?

Delivers semen during reproduction and provides a passage for urine.

What are erectile tissues?

Vascular tissues that fill with blood during erection.

What is the corpus spongiosum?

Erectile tissue surrounding the spongy urethra.

What are the corpora cavernosa?

Paired erectile bodies that become engorged during erection.

What is erection?

Engorgement of penile erectile tissue with blood.

What is ejaculation?

Expulsion of semen through the urethra.

Which autonomic division primarily promotes erection?

Parasympathetic nervous system.

Which autonomic division primarily promotes emission and ejaculation?

Sympathetic nervous system.

What are Sertoli cells?

Support cells in seminiferous tubules that nourish developing sperm.

What are Leydig cells?

Interstitial cells in testes that produce testosterone.

What is the blood-testis barrier?

A barrier formed by Sertoli cell junctions that protects developing germ cells.

What is spermatogenesis?

Production of sperm from germ cells in the testes.

What is the acrosome?

Enzyme-containing cap on the sperm head that helps penetrate the egg's coverings.

What is the function of the sperm tail?

Propels the sperm.

Where are mitochondria concentrated in a sperm cell?

The midpiece, providing energy for movement.