Male Reproductive System (Ch. 28)

Question 1

What do the testes produce?

Answer 1

Sperm

Question 2

The Testes and Scrotum

Answer 2

Testes are housed in scrotum (external sac, outside body cavity), divided into 2 compartments by a septum.

Cremaster muscle elevates or releases testes to maintain optimal temperature for sperm development (internal body temp. too high)

Average ~3 degrees cooler than body temp.

Question 3

Spermatic Cord

Answer 3

Spermatic cord = ductus deferens, fascia, testicular vessels and nerves

Extends from scrotum to inguinal canal.

Medial opening = superficial inguinal ring; Deep inguinal ring is where ductus deferens and testicular vessels enter abdomen

Question 4

Testes: Descent

Answer 4

Gubernaculum (fibrous tissue cord) extends form caudal end of developing testes through body wall and into skin of future scrotum.

Testes follow this path towards scrotum.

Spermatic cord (blood vessels, nerves, and sperm duct) follow testes

Question 5

The Testes: Tunica Vaginalis and Tunica Albuginea

Answer 5

Inside scrotum, each testis is surrounded by a Tunica Vaginalis.

Deep to tunica vaginalis is fibrous Tunica Albuginea.

Question 6

Seminiferous Tubules

Answer 6

Located within testes. Seminiferous tubules contain support cells (Sertoli cells) and dividing germ cells (future sperm).

Seminiferous tubule surrounded by CT that contains cells called Leydig’s cells. Leydig’s cells secrete testosterone.

Question 7

Spermatogenesis

Answer 7

Takes ~75 days to create mature sperm

Begin as spermatogonia then primary and secondary spermatocytes, spermatids, and sperm.

~400 million sperm produced per day from puberty to death

Question 8

Anatomy of a Mature Sperm Cell

Answer 8

Head contains a nucleus

Head is surrounded by an Acrosome - this has enzymes that will enable the sperm to penetrate the egg.

Mid-piece contains mitochondria for energy to propel the sperm

Tail is a flagellum for movement

Question 9

The Epididymis

Answer 9

The epididymis is the site of sperm maturation and storage: protein secretions nourish the sperm and help maturation.

Ejaculation: smooth muscle in walls of epididymis contract, expel sperm into ductus deferens.

Question 10

Ductus Deferens

Answer 10

aka Vas Deferens; transports sperm during ejaculation.

Extends form epididymis into pelvic cavity.

Question 11

Vasectomy

Answer 11

Surgical method of birth control where ductus deferens is cut and ends are tied off.

Female version is tubal ligation (uterine tubes).

Question 12

Urethra

Answer 12

Carries both urine and sperm

Includes prostatic urethra, intermediate [or membranous] urethra, and spongy urethra

Question 13

Accessory Glands: Seminal Vesicles

Answer 13

Seminal vesicles (posterior to bladder) produce portion of seminal fluid. Join with ductus deferens to form ejaculatory duct.

Question 14

The Penis

Answer 14

Penis delivers sperm into the female reproductive tract.

Question 15

Erectile Tissue

Answer 15

Spongy CT filled w/ vascular spaces

Erection = filling of erectile tissues with blood (parasympathetic control).

• -corpus spongiosum = ventral
• -corpora cavernosa = dorsal (paired)

Question 16

The scrotum is homologous to the ____ ____.

Answer 16

Labia majora

Question 17

The scrotal midline is homologous to the ____ ____.

Answer 17

Labia minora

Question 18

The glans penis is homologous to the ____ ____.

Answer 18

Glans clitoris

Question 19

The corpus spongiosum is homologous to the ____ ____ ____.

Answer 19

Bulb of vestibule

Question 20

The corpora cavernosa is homologous to the ____ ____.

Answer 20

Corpora cavernosa

Question 21

The testes are homologous to the ____.

Answer 21

Ovaries

Question 22

Accessory Glands: Prostate

Answer 22

Prostate (inferior to bladder) also produces some of seminal fluid. Holds prostatic urethra.

Question 23

Secretions from seminal, prostate, and bulbourethral glands + sperm cells = ____.

Answer 23

Semen

Question 24

The Ductus Deferens joins duct of seminal gland to form ____ ____, then passes through ____ and into urethra.

Answer 24

Ejaculatory Duct; Prostate

Question 25

The root of the penis is the ____ - where it attaches to the pelvis. The ____ is the free portion.

Answer 25

Base; Body

Question 26

The glans penis is the ____ end.

Answer 26

Enlarged

Question 27

Skin covering penis is loose. Where it extends around the glans is ____ (foreskin).

Answer 27

Prepuce

Question 28

Where do sperm travel (NOT the accessory organs)?

Answer 28

Sperm travel through epididymis, ductus deferens, ejaculatory duct, and out via the urethra.

Question 29

Along the way sperm pass what accessory sex glands?

Answer 29

Seminal vesicle, prostate gland, and bulbourethral glands.

Question 30

The Testes: Seminiferous Tubules

Answer 30

Testes are subdivided into 250-300 lobules containing seminiferous tubules.

Seminiferous tubules converge to straight tubule that carries sperm to Rete Testes.

Question 31

The Testes: Rete Testes

Answer 31

Rete Testis leads through efferent ductules to epididymis

Question 32

Hernia

Answer 32

Inguinal hernia when high pressure cause intestine to extrude through the deep inguinal ring
–very painful but easily repaired surgically

Question 33

Sertoli cells are ____ ____.

Answer 33

Support cells

Question 34

Leydig’s cells secrete ____.

Answer 34

Testosterone.

Question 35

Erectile Tissue: During sexual stimulation, arteries dilate and blood flow ____.

Answer 35

Increases

Question 36

Erectile Tissue: What maintains the erection?

Answer 36

Corpus cavernosum and spongiosum expand, compress veins that normally drain them…this maintains the erection.

Question 37

Erectile Tissue: Ejaculation under Sympathetic Control

Answer 37

Smooth muscle contraction squeezes semen to urethra; bulbospongiosus muscle at base of penis squeezes semen out of urethra.