1. Male repro.

Question 1

why do the testes hang outside the body

Answer 1

cooler temp. (35 degrees) required to maximise spermatogenesis

Question 2

describe sperm’s journey in the testes

Answer 2

i. sperm produced in seminiferous tubules…
2. collect in rete testes…
3. mature in epididymis…
4. transported in vas deferens (final maturation) to urethra

Question 3

label

Answer 3

Question 4

which type of cells make up the seminiferous tubules and the interstitium between them - what is their function

Answer 4

SERTOLI CELLS:

• make up walls of seminiferous tubules
• support sperm cell production from primary spermatocytes (from primordial germ cells)
• form blood-testis barrier via tight junctions

LEYDIG CELLS:

• contained in intersitial tissue separating tubules
• synthesise androgens, inc. testosterone (in response to LH)

Question 5

describe the tissues layers enclosing the testes

Answer 5

1. tunica albuginea: fibrous capsule enclosing testes and dividing parenchyma into lobules.
2. tunica vaginalis: covers anterior and lateral surfaces of each testicle. Derived from abdominal peritoneum - as processus vaginalis - so has parietal and visceral layers.

Question 6

describe the vasculature of the testes

Answer 6

arterial supply: via paired testicular aa. - arise directly from abdominal aorta and pass into scrotum through inguinal canal, contained within spermatic cord

venous drainage: pampiniform plexus (wrapped around testicular a.) drains into testicular vein. Acts as heat exchanger, cooling arterial blood before it reaches testes.

L testicular v. drains into L renal v. whilst R testicular v. drains directly into IVC.

Question 7

describe the lymphatic drainage of the testes and scrotum

Answer 7

• testes: lumbar and para-aortic nodes (L1)
• scrotum: superficial inguinal nodes

Question 8

describe the course of the spermatic cord

Answer 8

begins at deep inguinal ring… passes through inguinal canal… enters scrotum via superficial inguinal ring to reach posterior testes

Question 9

describe the 3 layers of the spermatic cord - where does each derive from

Answer 9

1. external spermatic fascia (from external oblique aponeurosis)
2. cremasteric muscle (from internal oblique aponeurosis) - acts to alter testes height for temp. regulation
3. internal spermatic fascia (from transversus abdominins)

Question 10

describe the cremasteric refex arc

Answer 10

i. stroke superior-medial part of thigh… sensed by ilioinguinal n. (afferent limb)…
ii. impulse along genital branch of genitofemoral n. (efferent limb)…
iii. cremaster muscle contraction and testis elevation on ipsilateral side

Question 11

describe the contents of the spermatic cord

Answer 11

• 3 arteries: testicular a., cremasteric a., a. to vas deferens
• 3 veins: pampiniform plexus/testicular v., cremasteric v., v. to vas deferens
• 3 nerves: ilioinguinal n., genital branch of genitofemoral n. (to cremaster), sympathetic testicular nn.

3 other: lymphatics (drain into para-aortic nodes), cremaster muscle, vas deferens

Question 12

how does the vas deferens transport sperm

Answer 12

persistaltic contraction (sympathetic innervation) of 3 SM layers in wall

Question 13

describe the anatomical course of the vas deferens

Answer 13

epididymis tail… inguinal canal… lateral pelvic wall (in close proximity to ischial spine)… turns medially to pass between bladder and ureter… joins seminal duct to form ejaculatory duct

Question 14

where is the bulbourethral gland located

Answer 14

posterolateral to membranous urethra in EUS

Question 15

describe the anatomical relations of the prostate gland

Answer 15

• inferior to neck of bladder
• supperior to EUS
• anterior to ampulla of rectum

Question 16

describe the 3 histological zones of the prostate - what are the clinical features of these

Answer 16

1. central zone
   - surrounds ejaculatory ducts
   - embryologically derived from mesonephric duct
2. transitional zone
   - surrounds urethra
   - embryologically derived from UGS
   - undergoes hyperplasia in BPH
3. peripheral zone
   - located posteriorly (can be felt against rectum in DRE)
   - embryologically derived from UGS
   - origin of most prostate cancers

Question 17

label these regions of the prostate

Answer 17

Question 18

label these regions of the penis

Answer 18

Question 19

describe the 3 main parts of the penis

Answer 19

1. ROOT:
   - located in superficial perineal pouch of pelvic floor (not visible externally)
   - contains 3 erectile tissues: 2 crura and bulb
2. BODY:
   - composed of 3 cylinders of erectile tissue: 2 corpus cavernosa and corpus spongiosum
3. GLANS:
   - distal expansion of corpus spongiosum containing exerternal urethral orifice

Question 20

describe the attachments of the root of the penis

Answer 20

attached to pubic bone and 2 muscles:

• bulbospongiosus - associated with bulb, contracts to empty urethra of any residual semen and urine
• ischiocavernosus - surround crura, contract to force blood from cavernous spaces in crura into corpus cavernosa to maintain erection

Question 21

describe the vasculature of the penis

Answer 21

1. arterial supply: via branches of internal pudendal a. (arises from internal iliac a.) - dorsal aa. of penis, deep aa. of penis and bulbourethral a.
2. venous drainage: deep dorsal v. of penis drains cavernous spaces (empties into prostatic venous plexus) and superficial dorsal vv. drain superficial structures

Question 22

describe the innervation of the penis

Answer 22

S2-S4 spinal cord segments and spinal ganglia:

• branch of pudendal n. (dorsal n. of penis) - sensory and sympathetic innervation to skin and glans penis
• cavernous nn. from prostatic n. plexus - parasympathetic innervation for vascular changes which cause erection

Question 23

how is the cylindrical nature of the penis maintained during erection

Answer 23

TUNICA ALBUGINEA: collagen fibres arranged at right angles (can rupture in broken penis)