Urogenital II

Question 1

Scrotum

Answer 1

• pouch of skin divided by a median septum into two compartments
• each compartment has a testis, an epididymis, and the distal part of the spermatic cord
• scrotal raphe - external mark of the scrotal septum
• left testis is usually farther caudal than the right

Question 2

Layers of the scrotum

Answer 2

• skin = thin, pigmented, covered with few hairs
• tunica dartos = smooth muscle layer, contraction causes the scrotal skin to retract and draw the testes close to the body

Question 3

scrotal ligament

Answer 3

connects the tunica dartos to the ligament of the tail of the epididymis

Question 4

Scrotum - cat

Answer 4

• located just ventral to anus

- lies on the short, caudally directed penis

Question 5

Testes

Answer 5

• located in scrotum obliquely with long axis running dorsocaudally
• nearly spherical
• enclosed in tunica vaginalis, spermatic and cremasteric fasciae, which are connected to tunica dartos
• epididymis is attached to the dorsolateral surface of testis, with head at the cranial extremity and tail at the caudal extremity

Question 6

Layers of the Testes

Answer 6

• scrotal skin
• tunica dartos
• scrotal septum
• external spermatic fascia
• parietal layer of vaginal tunic
• visceral layer of vaginal tunic
• tunica albuginea

Question 7

Attachments of the Testes

Answer 7

Proper ligament of the testis
-attaches the testis to the tail of the epididymis

Ligament of the tail of the epididymis
-attaches the tail of epididymus to the vaginal tunic and spermatic fascia

Scrotal Ligament
-attaches tunica dartos and ligament of tail of epididymis

Question 8

Epididymis: Function and Parts

Answer 8

• spermatozoa are stored before ejaculation
• lies along dorsolateral border of testis

Parts

• head (caput) = begins on cranial medial surface of testis but immediately twists toward lateral side
• body (corpus) = runs along the dorsolateral surface of testis
• tail (cauda epididumis) = attached to the caudal extremity of testis by the proper ligament of the testis

Question 9

As the epididymis continues craniodorsally, what is it?

Answer 9

ductus deferens

Question 10

mesorchium

Answer 10

visceral vaginal tunic that attaches the medial edge of the epididymis to the testis

Question 11

testicular bursa

Answer 11

• potential spaced created by the mesorchium passing medially over the lateral surface of the epididymis
• limited cranially and caudally by epididymal head and tail

Question 12

Ductus Deferens

Answer 12

-AKA Vas Deferens
-continuation of the tail of the epididymis
-passes cranially along
dorsomedial border of testis
-enters abdominal cavity at vaginal ring
-right and left ducts enter the genital fold

Question 13

Blood supply to the testis and epididymis

Answer 13

• testicular artery

- artery of ductus deferens

Question 14

Pampiniform Plexus

Answer 14

extensive plexus formed by the testicular vein

Question 15

Spermatic Cord

Answer 15

• begins at vaginal ring

- pass through inguinal canal during descent of testis

Question 16

Anatomical Spermatic Cord

Answer 16

• ductus deferens and its vessels
• mesoductus deferens
• testicular artery
• testicular veins that form pampiniform plexus
• lymphatics of testis and epididymis
• testicular nerve plexus
• mesorchium

Question 17

Surgical/ Clinical Spermatic Cord

Answer 17

• all features of anatomical spermatic cord
• cremaster muscle
• parietal vaginal tunic

Question 18

Castration: Open vs. Closed

Answer 18

Open = opens the vaginal tunic

Closed = w/o opening the vaginal tunic

Choice is based on surgeon and size of animal (larger - more open; smaller - more closed)

Question 19

Male Accessory Sex Glands

Answer 19

• ampullary gland

- prostate

Question 20

Prostate

Answer 20

• completely surrounds urethra at neck of bladder
• dorsal surface is covered by peritoneum
• ventral surface is retroperitoneal
• dorsally bound by rectum
• ventrally bound by pubis symphysis and ventral abdominal wall
• median septum divides it into right and left lobes

Question 21

Where do the 2 ductus deferens enter the prostate?

Answer 21

• craniodorsal surface

- Run through prostate to open into urethra by two slits on each side of a hillock, the colliculus seminalis

Question 22

Three divisions of the Penis

Answer 22

Root

• left and right crura
• bulb of the penis

Body
-two adjacent corpora cavernosa

Glans

• bulbus glandis
• pars longa glandis

Question 23

T/F: In the non-erect state, the glans is entirely withdrawn into the prepuce.

Answer 23

True

Question 24

Root of the Penis

Answer 24

• crus of the penis
• proximal end of corpus cavernosum penis
• originate from ischiatic tuberosity
• surrounded by ishiocavernosus muscle

Question 25

Bulb of the Penis

Answer 25

- lies between the crura - partially bilobed - not complete separation - continuous with corpus songiosum surrounding caudal part of urethra - externally covered by bulbospongiosus muscle

Question 26

Body of the Penis

Answer 26

- body begins where the 2 crura join distal to the bulb - includes corpus cavernosa, corpus spongiosus, and urethra - enveloped by tunica albuginea

Question 27

Glans of the Penis

Answer 27

- pars longa glandis - bulbus glandis Also surrounds the os penis

Question 28

Bulbus glandis

Answer 28

- barrel-shaped cavernous expansion of corpus spongiosum - surrounds proximal third of os penis - not distinct in non-erect stage - functions to provide the "tie" or "lock" during copulation - separated from pars longa glandis by c.t. septum

Question 29

Pars longa glandis

Answer 29

- no connection between it and the corpus spongiosum | - short, large vein on each side drains pars longa glandis into cavernous bulbus glandis

Question 30

Os penis

Answer 30

ossification of corpora cavernosa

Question 31

Prepuce

Answer 31

fold of skin that covers glans of penis in the retracted state Four parts: External Lamina -haired skin on outer surface -continuous with skin of abdominal wall Internal Lamina - in contact with penis - terminates at the fornix Preputial orifice -external and internal lamina meet Preputial fornix -internal lamina reflect onto glans penis

Question 32

Muscles of the Penis

Answer 32

- Ischiocavernosus - Bulbospongiosus - Retractor penis - Ischiourethralis

Question 33

Ischiocavernosus m.

Answer 33

- ischiatic tuberosity | - encloses the crura

Question 34

Bulbospongiosus m.

Answer 34

- surrouds bulb of penis | - arises from external anal sphincter

Question 35

Retractor penis m.

Answer 35

- mainly smooth muscle | - arises from first 2 caudal vertebrae

Question 36

Ischiourethralis m.

Answer 36

- originates from ischiatic tuberosity | - inserts into fibrous ring that encircles dorsal vein of penis

Question 37

What is the erectile tissue found in the crus of the penis?

Answer 37

corpus cavernosum