Lecture 1 - The Male Reproductive System Flashcards
On a cross section of the male reproduction system, be able to label:
- Seminal vesicle
- Ductus deferens
- Prostate
- Ejaculatory duct
- Rectum
- Anal canal & aperture
- Bladder
- Urethra
- Testes
EZ brah u mirin?
On a microstructure picture of the testes, identify the seminiferous tubules, tunica vaginalis, tunica albuginea, rete testis, and the head, body and tail of epididymis.
What are the roles of these structures within the testes?
- Seminiferous Tubules = hollow tubes w/epithelial lining, sperm initially formed here.
- Tunica Vaginalis = A peritoneal sac surrounding testes formed from peritoneum in abdomen, permitting testes to move freely in scrotum
- Tunica albuginea = The capsule, dense connective tissue holding the seminiferous tubules together.
- Rete Testis = Seminiferous tubules converge together
- Epididymis = Transport sperm from the Rete Testis to the vas deferens
What is a hydrocoele?
How is it tested for & differentiated from a solid mass, i.e.: a tumour?
- A hydrocoele is an accumulation of clear fluid within the layers of the tunica vaginalis, leading to scrotal swelling
- Shining a torch will cause transillumination (it will light up), whereas a solid mass will stay opaque
What are the roles of Sertoli and Leydig cells within the seminiferous tubules?
Leydig cells = produce testosterone under control of LH
Sertoli cells = facilitate progression of germ cells to spermatozoa (develop sperm)
Describe the blood supply into and out of the right and left testis.
Why does the left testes usually sit lower than the right?
Right = receives right testicular artery (branching off abdominal aorta), right testicular vein drains directly into IVC.
Left = receives left testicular artery but left testicular vein drains into renal vein, not directly into IVC.
Left testis sits lower, as it has greater amount of resistance to drainage as it pass to pass through renal vein.
What deformity predisposes a male to be more susceptible to testicular torsion?
Why is urgent management of this condition required?
- Bell-Clapper Deformity, where the tunica vaginalis entirely evaginates the testes, allowing testes to twist/rotate
- Twisting can lead to compartment syndrome, blockage of blood supply and the testes becoming necrotic
Why are the testicles unable to swap sides?
Due to the scrotal septum separating the left and right sides
How is the spermatic fascia that surround the testis formed?
The testes evaginate the abdominal wall muscles (3 of them) like pushing a finger into clingfilm, as they are pulled downwards by the gubernaculum (see slide 11 for diagram)
Name + Identify the 3 fascial layers, 3 arteries/veins, 3 nerves and 3 other structures present within the spermatic cord.
Fascial layers = Internal spermatic fascia (derived from external oblique), External spermatic fascia (derived from transversus abdominus) & Cremasteric fascia (derived from internal oblique)
Arteries/Veins = Testicular artery, Testicular Vein & Artery to cremaster muscle
Nerves = Nerve to vas, Nerve to cremaster & Ilioinguinal nerve
What is the cremasteric reflex + what does it test?
What branch of the ANS mediates erection + ejaculation?
- Cremasteric reflex is when inner part of medial thigh is touched, causing cremaster muscle to pull up ipsilateral testicle toward inguinal canal. Tests L1 spinal level.
- Erection = Parasympathetic (causing vasodilation of penile arterioles)
- Ejaculation = Sympathetic (causing vasoconstriction)
Describe the course of the ductus (vas) deferens
Ascends posterior to testis, medial to epididymis, travelling superiorly but posteriorly to spermatic cord. Then crosses inguinal canal, emerging from the spermatic cord at the deep inguinal ring.
Then curves round crossing superiorly to the ureter, then eventually joining the duct of the seminal vesicle to form the ejaculatory duct, which drains its contents into the urethra
What are the 3 zones of the prostate?
What part of the prostate is felt on rectal examination?
Enlargement of which part causes urethral obstruction & why?
- Transitional, Central + Peripheral
- Peripheral zone
- Transitional zone, as it surrounds the urethra as it enters the prostate gland
What are the 3 blocks of erectile tissue that can be seen in a cross section of a penis?
Which part transmits the urethra & why does this part get much less turgid?
- 2 x corpora cavernosa & 1 x corpus spongiosum
- Corpus spongiosum (much less turgid as it would otherwise block ejaculate from leaving urethra)
How is blood supplied to the penis?
Primary blood supply from internal iliac artery giving off multiple branches to form dorsal arteries of penis.
Why is it vital to establish the anatomy of a transgender man?
Need to establish whether trans-men have a cervix as cervical screening for cancer will still be necessary.
