9. Male Reproductive system Flashcards
Describe the seminiferous tubules.
They are the site of spermatogenesis. The epithelium is composed of supporting Sertoli cells and spermatogenic cells.
Describe Sertoli cells and their function.
They are irregular columnar cells that extend from the basal laina to the lumen and make up the blood-testis barrier. Tight junctions between adjacent Sertoli cells divide the seminiferous tubules into a basal component (containing spermatogonia) and an adluminal compartment (containing spermatocytes and spermatids). They synthesize testicular androgen-binding protein, which helps maintain the high androgen levels within the seminiferous tubules. The androgen is necessary for spermatogenesis.
What are the spematogenic cells?
They are the germ cells located between the Sertoli cells. They consist of spermatogonia, primary and secondary spermatocytes, spermatids, and spermatozoa.
How many spermatozoa are in a single ejaculation?
200 to 600 million in a single ejaculation; 60,000 spermatozoa per cubic millimeter of seminal fluid.
Which cells secrete most of the testosterone (~80%)?
Interstitial cells of Leydig. They are located between the seminiferious tubules in the interstitial connective tissue.
What anterior pituitary gland hormone is responsible for the command to produce testosterone?
Luteinizing hormone (LH).
What is the tubuli recti?
It connects the seminiferous tubules with the rete testis. Continuous production of testicular fluid by the Sertoli cells helps to move the gametes out of the seminiferous tubules.
What is the Rete testi?
It consists of an anastomosing labyrinth of channels within the mediastinum that coverge toward the efferent ductules.
What is the ductus epididymis?
A single, elongated tortuous duct that may be 6 meters or more in length. Lined by pseudostratified epithelium, containing stereocilia.
Where in the male reproductive organ does the sperm undergo maturation and develop increased motility and fertilizing capacity?
In the ductus epididymis.
What is the ductus deferens?
AKA vas deference, it is a tube that contains a thick muscular coat, which dilates distally into the ampulla. The ampulla gradually narrows to form the ejaculatory duct, which penetrates the prostate gland and empties into the urethra.
What type of epithelium lines the prostatic portion of the urethra?
Transitional epithelium [Pro T]
What type of epithelium lines the penile distal portion of the urethra?
Stratified epithelium [PES]
Which 3 parts of the male reproductive organ can sperm be stored?
Efferent ductules, epipdidymis, and proximal ductus deferens.
What are the 3 accessory glands of the male reproductive system?
Seminal vesicles, prostate gland, and the bulbourethral (Cowper) gland.
