Male Urogenital Triangle

Question 1

What does the root of the penis consist of?

Answer 1

crura and bulb and associated muscles

Question 2

What attaches to the internal surface of each ischial ramus and is continuous with corpora cavernosa?

Answer 2

the crura of penis

Question 3

what muscle surrounds the crura of the penis?

Answer 3

ischiocavernosus m.

Question 4

what is the function of the ischiocavernosus m.?

Answer 4

forces blood from crus into corpus cavernosum of penis, compresses deep dorsal v. of penis => erection

Question 5

What is the innervation for the crura of the penis?

Answer 5

deep perineal n. (from pudendal n.)

Question 6

What is the bulb of the penis?

Answer 6

central large mass of erectile tissue inferior to perineal membrane

Question 7

The bulb of the penis is continuous with what structure?

Answer 7

corpus spongiosus

Question 8

Which muscle surrounds the bulb of the penis?

Answer 8

bulbospongiosus m.

Question 9

What is the function of the bulbospongiosus m.?

Answer 9

• forces blood into corpus spongiosum
• compresses deep dorsal v. of penis to increase turgidity of penis
• aids in emptying residual urine/semen from spongy urethra

Question 10

How many muscles are located within the body of the penis?

Answer 10

essentially none, there may be a few fibers from ischiocavernosus or bulbospongiosus mm. though

Question 11

What surrounds the corpora cavernosa?

Answer 11

thick, fibrous tunica albuginea

Question 12

Which structure extends distally to form the glans penis?

Answer 12

corpus spongiosum, the CC has nothing to do with this

Question 13

The tunica albuginea in the corpus spongiosum is much (thinner/thicker) than in the cavernosa?

Answer 13

thinner and more extensible

Question 14

What are the parts of the glans penis?

Answer 14

corona, neck, prepuce, frenulum of prepuce; (external urethral orifice at distal end)

Question 15

What are the functions of the superficial penile fascia?

Answer 15

mobility of skin on penis and contains the superficial neurovasculature supplying the penile skin

Question 16

Where do the suspensory ligaments of the penis attach?

Answer 16

anterior surface of pubic symphysis to root of penis, fusing with deep penile fascia (anchoring erectile bodies to pubic symph.)

Question 17

The artery of bulb, deep a. of penis and dorsal a. of penis are all branches off which artery?

Answer 17

internal pudendal a.

Question 18

What does the dorsal a. of the penis supply?

Answer 18

fascial CT and the majority of penile skin

Question 19

Which artery is responsible for erection of the penis?

Answer 19

deep a. of the penis

Question 20

What does the artery of the bulb supply?

Answer 20

bulb (lol), corpus spongiosum, and spongy urethra

Question 21

What does the external pudendal a. branch from and what does it supply?

Answer 21

branch from femoral a. and supplies proximal penile skin

Question 22

what vein drains the erectile tissue of the penis?

Answer 22

deep dorsal vein of penis (–>prostatic venous plexus –> internal iliac v.)

Question 23

What vein drains skin?

Answer 23

superficial dorsal vein of penis (–>superficial external pudendal v. –> external iliac v.)

Question 24

where does the lymph from the penis drain to?

Answer 24

superficial inguinal nodes

Question 25

What provides sensory innervation of skin and glans penis?

Answer 25

dorsal nerve of penis (terminal branch of pudendal n.)

Question 26

what nerve carries parasympathetic fibers from the prostatic plexus of nerves?

Answer 26

cavernous nerve… responsible for innervating the deep a. of penis/erection

Question 27

Is erection controlled by sympathetics or parasympathetics?

Answer 27

parasympathetics

Question 28

Is emission controlled by sympathetics or parasympathetics?

Answer 28

sympathetics, via peristaltic action of ductus deferens and accessory glands

Question 29

Ejaculation is caused by contraction of what muscle?

Answer 29

bulbospongiosus m. which expels semen though spongy urethra

Question 30

After ejaculation, which stream (haha) of nerves [para/symp] function on the tunica media in the deep a.?

Answer 30

sympathetics cause constriction of tunica media to decrease blood flow to the area