Male ducts and accessory glands Flashcards
What ducts are involved in male repro?
Seminiferous tubules Rene testis Efferent ductules Epididymis Vas Ejaculatory duct Urethra
Where is the rene testis?
A network of tubules embedded in the capsule on the posterior side of the testis
What happens in the rene testis?
Sperm partially mature here, moved along by a flow of secretions from Sertoli cells and cilia found on some of the rete testis cells
What are the efferent ductules?
About 12 small efferent ductules arise from rene testis and carry the sperm to the epididymis
What epithelium lines the efferent ductules?
Cells here are ciliated- to move sperm
What happens in the epididymis?
SIte of sperm maturation and storage
Describe the epididymis
Comma-shaped organ, with a head, body and tail
Lies along the posterior border of the testis
Consists of one tightly coiled tube, about 6m long
What epithelium and why lines the epididymis?
Pseudostratified epithelium cells, some have long stereocilia to absorb excess testicular fluid
How long must sperm stay in the epididymis?
How long can they stay?
Sperm are here for 10-14 days while their motility increases and they become fertile
Sperm may remain here for up to 1 month, and are then expelled or reabsorbed
What does the epididymis absorb?
This duct absorbs 90% of the fluid secreted by the testis itself
How long is the vas deferens and where does it run?
45 cm long, runs from epididymis through inguinal canal,and into the pelvic cavity
Loops medially over the ureter and descends along the posterior bladder wall
The vas widens at the end, forming the _______ of the ductus deferens, and ends by uniting with the duct of the seminal _______ to form the _______ duct
ampulla
vesicle
ejaculatory
What kind of epithelium lines the vas?
How are sperm moved down the vas?
Pseudostratified epithelium
A muscular tube, peristaltic contractions to move the sperm
What is a vasectomy?
“the cutting of the vas”
A physician makes a small incision in the scrotum, and then cuts through and ties off each vas deferens
Sperm are produced, but eventually deteriorate and are phagocytosed
Can reverse, 50% success rate
What is the ejaculatory duct?
2 cm where the vas joins duct from 2 seminal vesicles
Enters the prostate gland and joins into the prostatic urethra
Is the last of the spermatic ducts
How long is the male urethra? What two substances does it convey?
18 inches
Urine and sperm
What are the 3 parts of the urethra?
Prostatic urethra
Membranous urethra
Spongy urethra
How long is the prostatic urethra, what epithelium?
2.5 cm, ciliated epithelium
How long is the membranous urethra, and what epithelium?
0.5 cm, transitional epithelium
Where does the membranous urethra go?
Passes thru urogenital diaphragm, the muscular floor of pelvic cavity
How long is the spongy urethra, where is it, and what epithelium lines it?
15 cm, passes through penis, transitional to stratified squamous
What are the 3 male accessory sex glands?
Seminal vesicles-2
Prostate gland
Bulbourethral glans-2
What are the seminal vessicles?
What do they secrete?
Sac-like glands at the base of the bladder
Size of your pinkie
Secretes a yellowish, viscous, alkaline fluid that contains fructose to nourish sperm
What is the prostate?
What does it secrete?
A single, donut shaped gland, that encircles prostatic urethra and ejaculatory duct
Size of a peach pit
Secretes a thin, milky white fluid that contains calcium
What are the bulbourethral glands?
What do they secrete?
Contain trace semen
Look like a bulb, are pea-sized, inferior to prostate
Aka Cowper’s glands
Produce a thick, clear mucus that lubricates the urethra
Describe semen
A mixture of sperm and secretions from the three accessory glands
Milky, white, somewhat sticky
What % is sperm in ejaculate?
What is the threshold for infertility?
2-5 mL and only 10% sperm in each ejaculation, but 150m sperm/mL
If count is less than 20m/mL then considered infertile
What composes ejaculate, by %?
60%- Fluid from seminal vesicles
30%- Fluid from prostate
10%- Sperm
Trace- secretions from bulbourethral glands
