The Male Reproductive System Flashcards
List the male external genital organs
- penis
- scrotum
List the male internal genital organs (duct system)
- testes
- epididymides
- ductus deferentes
- seminal glands
- ejaculatory ducts
- prostate
- Cowper glands
Describe the penis
Long shaft or body and an enlarged bulbous shaped tip called the glans which is prolonged by a foreskin called the prepuce.
Attached root called Radix in the perineum and a free pendulous body which is completely covered with skin.
Contains spongy tissues that become turgid and erect when filled with blood.
What are the erectile tissues of the penis ?
- corpus spongiosum : traversed by urethra
- corpora cavernosa : contains most of the blood in the penis
What are the suspensory ligaments of the penis ?
- the fundiform ligament
- the triangular ligament
What are the blood supplies of the penis ?
Three pairs of arteries that are all branches from the internal pudendal artery :
- artery to the bulb
- deep artery of the penis
- dorsal artery of the penis
Mainly the dorsal vein - all the veins return the blood to the internal pudendal vein.
What is the innervation of the penis ?
- pudendal nerves
- perineal nerves
- posterior scrotal and dorsal nerves
- pelvic splanchnic nerves (S2 and S3 nerves)
Define the scrotum ?
Pouch like structures that hang behind the penis.
Houses and protects the testes and spermatic cords and keeps the testis at a temperature of about 2 to 4 degree lower than the body temperature.
What gives its wrinkle appearance to the scrotum ?
The Dartos muscle
What is the role of the cremaster muscle ?
Contracts to pull the scrotum closer to the body for a higher temperature when outside temperature lowers.
What is the raphe ?
The midline between right and left parts of the scrotum
What is the scrotum blood supply ?
Superficial and deep external pudendal arteries branches from the internal pudendal arteries.
External pudendal veins
What is the innervation of the scrotum ?
- ilio inguinal nerve (L1)
- scrotal branches of the perineal nerve (S3)
- posterior femoral cutaneous nerve (S2)
What is the function of the testes ?
Produce sperm and testosterone
What encloses the seminiferous tubules ?
Interstitial cells of Leydig producing testosterone in the presence of luteinizing hormone.
What is the direction of sperm in the testes ?
From the rete testis to the epididymis
Which is the name of the tissue protecting the testes ?
The tunica albuginea
What is the blood supply of the testes ?
Testicular arteries running from the aorta
The veinous drainage takes place in the pampiniform plexus
What is the innervation of the testes ?
Sympathetic
Describe the epididymis
Attached to the postero lateral surface of the testes
Firm single tube of approximately 7m highly coiled and packed together by fibrous tissue
Divided into three parts : head, body and tail of the epididymis
What is the role of the epididymis ?
Site for maturation and storage of spermatozoa
What continues the epididymis at its tail ?
The vas deferens
What is the blood supply of the epididymis ?
Branches of the testicular artery
Venous returns into the pampiniform plexus
What is the innervation of the epididymis ?
Sympathetic nerves from the coeliac ganglion
Describe the ductus deferens
Continues the epididymis
Thick muscular wall and minimal lumen
Forms the primary component of the spermatid cord
Enlarges to form the ampulla of ductus deferens before terminating by joining the duct of the seminal gland to form the ejaculatory duct
Describe the seminal glands
Elongated structure of approximately 5 cm
Lies between the fundus of the bladder and the rectum
What is the role of the seminal glands ?
Secrete a thick alcaline fluid with fructose and coagulating agent that mixes with the sperm as they pass through the ejaculatory duct and the urethra
What composes the ejaculatory duct ?
Duct of the seminal gland + ductus deferens
What is the blood supply of the seminal glands ?
Branches from the inferior vesicle and middle rectal arteries and vena comitans
What is the innervation of the seminal gland ?
Pelvic plexus
Describe the Ejaculatory ducts
Tubes that arise from the union of the ducts of the vas deferens and of the seminal glands
Arises next to the neck of the urinary bladder
Pierces the prostate and empty in the urethra that runs through the prostate gland
What are the blood supplies of the ejaculatory duct ?
Branches of the superior and/ or inferior vesicle arteries
Veinous drainage goes into the veina comitans that joins into the prostatic and vesicle veinous plexus
Describe the prostate
Largest accessory gland 2/3 glandular 1/3 fibromuscular Composed of 3 zones : - central zone - transitional zone - peripheral zone
What is the role of the prostate ?
Secretion of proteolytic enzymes into the semen which acts to break down clotting factors in the ejaculate, allowing semen to remain in a fluid state. The proteolytic enzymes leave via the prostatic ducts.
Why can a physician examine the prostate ?
Posterior to the prostate lies the ampulla of the rectum allowing the physician to palpate the size of the prostate = Digital Rectal Examination
What are the blood supplies of the prostate ?
Branches of the internal illiac artery, including the inferior vesicle arteries, internal pudendal and middle rectal arteries.
Veinous drainage through prostatic veinous plexus that drains into the internal iliac veins.
What is the innervation of the prostate ?
Pelvic splanchnic nerves
Describe the bulbo-urethral glands
Accessory glands also called Cowper glands `
Lie posterolateral to the intermediate part of the urethra
They empty directly into the urethra
What is the function of the bulbo-urethral glands ?
They secrete slippery fluids that lubricate the glans of the penis when it is erect.
What is the blood supply of the bulbo-urethral glands ?
One of the branches of the common penile artery : the bulbo-urethral artery
