WEEK 9 MALE PERINEUM AND PELVIC ORGANS FINISHED Flashcards
What does the male perineum include?
The anal canal, the intermediate and spongy parts of the urethra, and the root of the penis and the scrotum.
What are the 4 parts of the male urethra?
Preprostatic urethra (urethra in the bladder neck) Prostatic urethra Intermediate urethra (membranous) Spongy urethra (penile)
What is the intermediate urethra?
Shortest section of the male urethra (1-2 cm)
Begins at the apex of the prostate and ends at the bulb of the penis.
x
What is the spongy urethra?
x
What is the scrotum? What is it made of?
A cutaneous fibromuscular sac.
Its an out pouching of the anterior abdominal wall.
Contains the testes, epididymides and distal ends of the spermatic cord.
What is the optimal temperature for spermatogenesis?
1.2 degrees lower than core temperature.
What is spermatogenesis? How many are made per day?
Sperm production. >100 million per day.
What is the arterial supply to the scrotum?
Anterior aspect - external pudendal arteries (off femoral)
Posterior aspect - internal pudendal arteries, also branches from the testicular and cremasteric arteries (off inferior epigastricartery (Ext Iliac artery))
What is the innervation of the scrotum?
Anterior aspect - anterior scrotal nerves derived from ilioinguinal (L1) and genitofemoral (L1,L2) nerves
Posterior aspect - Posterior scrotal nerves derived from the superficial perineal nerves and the perineal branch of the posterior femoral cutaneous nerves (S2,S3)
What are the layers of the scrotum? DONT NEED TO LEARN THE DIFFERENT LAYERS, JUST KNOW THAT THERE IS MUSCLES THAT ARE SMOOTH THAT HELP TO REGULATE THE TEMP OF THE TESTES
Skin Superficial fasic and dartos mm External spermatic fascia Cremaster Cremaster fascia Internal spermatic fascia Tunica vaginalis
What is the testes?
A ovoid organ that is suspended in the scrotum by the spermatic cord.
It produces sperms/spermatozoa (male germ cells)
Also produces hormones) principally testosterone
Where in the testes are sperm produces? Which testis is lower (usually)?
In long convoluted seminiferous tubules that are around 70cm long. These are joined by straight tubules to the tete testis. Usually the left is more inferior suspended lower than right
What is each testis covered by?
A tough, fibrous coat - the tunica albuginea which also extends into the testes forming the septa.
What is the tunica vaginalis? What are the 2 layers of this?
A visceral layer that covers the surface of each testis except where the testis attaches to the epididymis and spermatic cord.
A further layer called the parietal layer of the tunica vaginalis, is separated from the visceral layer of the tunica vaginalis by a cavity which contains a small amount of fluid.
What is the arterial supply of the testis?
Testicular arteries - anterolateral aspect of the abdominal aorta just inferior to the renal arteries.
They pass retro-peritoneally (externally/ posterior to the peritoneum)
Arteries anastomose with the artery of the ductus deferens.
What is the purpose of the 2 layers of the tunica vaginalis?
Allows the testis to freely slide past each other
Innervation of the testis?
Testicular plexus on the testicular artery. PNS fibres from the vagus nerve. Sympathetic fibres T10-T11
What is the epididymus? Where is it? What happens in it?
A highly convoluted tubule (7 m long) which connects the testis to the vas deferens.
Lies on posterior surface on the testis.
Sperm pass along the tube over several days during which time they mature.
What happens in the lower part of the epididymus?
Sperm are stored and concentrated until ejaculation
What are sertoli cells? What do they do?
They secrete tubular fluid into the epididymus which move along the sperm.
What part of the epididymus is not covered by the tunica vaginalis?
Posterior margin
What are the 3 parts of the epididymus?
-a head: the superior expanded part that is composed of lobules formed by the coiled ends of 12 -14 efferent ductules
-a body: that consists of the convoluted duct of the epididymis
-a tail: which is continuous with the ductus deferens
(the duct that transports sperm from the epididymis to the ejaculatory duct)