ANA 212 Perineum

Question 1

What is the male perineum made up of?

Answer 1

external genitalia (distal parts of the male urethra, scrotum, and penis)
II. perineal muscles
III. anal canal

Question 2

Briefly describe the scrotum

Answer 2

Scrotum
• is a large pendulous sac of skin located below and behind the penis.
•It is considered as an out-pouching of the lower part of the anterior abdominal wall

Question 3

Content of the scrotum

Answer 3

Testes
Epididymis
Lower parts of the spermatic cord

Question 4

Describe the external features of the scrotum

Answer 4

The median ridge or raphe indicates the line of fusion of the two halves of the scrotum.
This ridge is continued forward in the midline to the undersurface of the penis and backward in the midline of the perineum to the anus
•The skin is rugose (corrugated/wrinked) and dark in colour
•rugosity due to the presence of subcutaneous dartos muscle.
•The left half of the scrotum hangs lower than the right half, because the left spermatic cord is longer than the right spermatic cord

Question 5

A rterial supply of scrotum

Answer 5

VI. Superficial external pudendal artery.
VII. Deep external pudendal artery.
VIII.Scrotal branches of the internal pudendal artery.
IX. Cremasteric artery

Question 6

Venous drainage of the scrotum

Answer 6

Scrotal veins accompany the arteries

Question 7

lymphatic drainage of the scrotum

Answer 7

drain into the superficial inguinal lymph nodes

Question 8

Innervation of the scrotum

Answer 8

•Anterior scrotal nerves supplying the anterior surface.
•Posterior scrotal nerves supplying the posterior surface
•Genital branch of the genitofemoral supplying the anterolateral surface
•Perineal branches of the posterior cutaneous nerve of thigh supplying the posteroinferior surface

Question 9

Clinical anatomy of he scrotum

Answer 9

•Scrotal elephantiasis: It is a clinical condition characterized by a massive swelling and enlargement of the scrotum due to accumulation of interstitial fluid in the scrotal wall following blockage of lymph vessels by slender worms of filariasis (Wuchereria bancrofti).

Question 10

Briefly describe the penis

Answer 10

It is the male organ of copulation
•It is transversed by the urethra which provides an outlet for urine and semen
•It is capable of becoming hard and erect due to its engorgement with blood, a requirement for its intromission into the vagina

Question 11

Parts of the penis include

Answer 11

I.Root or radix
II.Body or corpus
III.Glans penis

Question 12

Does the penis have muscles?

Answer 12

Except for a few fibers of the bulbospongiosus near the root of the penis and the ischiocavernosus that embrace the crura, the penis has no muscles.

Question 13

Describe the glans penis

Answer 13

• Distally, the corpus spongiosum expands to form the glans penis
•The margin of the glans projects beyond the ends of the corpora cavernosa to form the corona of the glans
•The corona overhangs an obliquely grooved constriction, the neck of the penis,
•The neck of the penis seperates the glans of the penis from the body of the penis.
•Near the tip of the glans is the slit-like opening of the spongy urethra called the external urethral orifice (meatus)

Question 14

Describe the coverings of the penis

Answer 14

•It is covered by a thin skin and fascia
•At the neck of the penis is the attachment of a fold of skin called the prepuce (foreskin)
•The prepuce (foreskin) covers the glans to a variable extent
•A median fold called the frenulum passes from the prepuce to the urethral surface of the glans