S1) The Man Flashcards
Label the following structures in the male reproductive system:
What are Sertoli cells?
Sertoli cells are the somatic cells of the testis that are essential for testis formation and spermatogenesis
Where are Sertoli cells found?
Found in the seminiferous tubule
What are Leydig cells and what do they do?
- Leydig cells are interstitial cells of Leydig, are found adjacent to the seminiferous tubules in the testicle.
- Produce testosterone in the presence of LH
explain what happens during testicular torsion
→ The spermatic third becomes fully invaginated within the Tunical vaginalis
⇒ The spermatic cord twist upon itself
⇒ This occludes the blood supply (testicular artery)
⇒ Pressure builds up and necrosis of testis results
=> have 12 hours to fix
Can testicles swap sides?
No, as a scrotal septum separates the two testicles
Describe the process in which the testes push through the abdominal wall
- The testes evaginate the abdominal wall as they are pulled through by the gubernaculum
- forms an inguinal Canal
- no hole is punctured and so prevents a hernia from forming
- This forms the spermatic fascia (made of layers of abdominal muscle)
→ spermatic cord arises from the the abdominal cavity through the inguinal canal to the scrotum.
What are the three fascial layers in the spermatic cord and what are they derived from?
- Internal fascia → transversalis fascia
– Cremasteric fascia → internal oblique muscle
- External fascia → external oblique muscle
Identify the three arteries supplying the spermatic cord
- Testicular artery
- Artery to vas
- Cremasteric artery
Identify the three veins draining the spermatic cord
- Testicular vein
- Vein to vas
- Cremasteric vein
Identify the three nerves innervating the spermatic cord
- Ilioinguinal nerve
- Nerve to cremaster (genital branch of genitofemoral nerve)
- Sympathetic
What happens during a vasectomy?
- Vas deferens are sectioned
- Sealed/tied to prevent sperm from entering into the urethra
- Prevents fertilisation
What are the consequences to the sperm count after a vasectomy?
Sperm count reduces
What are the consequences to the composition of the ejaculate after a vasectomy?
- No visible difference
- Semen is made in accesory glands and sperm only composes 2-5%
Which nerve is responsible for the cremasteric reflex?
Muscular reflex of genitofemoral nerve in males
What does the prostate do?
- Maintains urinary continence (surrounds urethra)
- Creates an alkali secretion
- Propels seminal fluid into urethra during ejaculation
- contributes to (25-30% of semen)
Which zones in the prostate does cancer and BPH affect?
- Benign prostatic hyperplasia affects transitional zone
- Prostate cancers tend to be in peripheral zone
What are the functions of the penis?
- Expulsion of urine via urethra
- Deposition of sperm in female genital tract
Describe the processes that guide erection
- hight blood circulation causes an erection in the penis
- Vasodilatation in penile arterioles, and compression of veins results in erection (parasympathetic)
- Erection is terminated by vasoconstriction (sympathetic)
- when someone has erectile dysfunction they must take viagra because it is a vasodilator
Which nervous system orchestrates ejaculation?
Ejaculation is a complex process primarily orchestrated by the sympathetic system
Which artery is the main blood supply to the penis?
Pudendal artery
On the following figure of the testis, identify:
- Pampiniform plexus of veins
- Testicular artery
- Vas deferens
- Epididymis
- Seminiferous tubules
Where is the origin of the testicular arteries?
Branch of abdominal aorta, inferior to renal arteries
Describe the venous drainage of the right and left testis
- Right testis: inferior vena cava
- Left testis: renal vein
Discriminate between the lymphatic drainage of the scrotum and that of the testis
- Scrotum – drains into inguinal lymph nodes
- Testes – drains into para-aortic lymph nodes
What is the cremasteric reflex?
- The cremasteric reflex can be stimulated by stroking the superior and medial part of the thigh
- Produces immediate contraction of the cremaster muscle, elevating the testis to the side that has been stimulated
From which layers of the anterior abdominal wall are the fascial coverings of the spermatic cord derived?
- External oblique muscle
- Internal oblique muscle
- Transversus abdominis muscle
On the diagram below, label:
- The vas deferens
- The spermatic cord
- External spermatic fascia
- Cremaster muscle
- Cremasteric fascia
- Internal spermatic fascia
- Tunica vaginalis
What are the contents of the spermatic cord?
- Nerve to cremaster (genital branch of genitofemoral nerve)
- Artery & vein to vas deferens
- Pampiniform plexus of testicular veins
- Sympathetic nerve
- Cremasteric artery and vein
- Ilioinguinal (on the outside, in superficial to external spermatic fascia)
- Tunica vaginalis
- Testicular artery & vein
- Lymph vessels
- Vas deferens
Mnemonic: Not All People Steal Cookies In The Teacher’s Lovely Van
Which structures of the male reproductive system have smooth muscle that contract in peristaltic waves during emission?
- Seminal vesicles
- Prostate
- Vas deferens
Identify the three accessory glands of the male reproductive system
- Seminal vesicles
- Bulbourethral gland
- Prostate gland
Describe the contents of the seminal vesicle secretions as well as its overall contribution to the seminal fluid
- Secretions contain alkali, fructose, prostaglandins and clotting factors
- Compose 70% of total semen volume
Describe the contents of the bulbourethral gland secretions and its overall function
- Produces an alkali-rich mucous fluid, secretions that reduce friction
- Neutralises residual acidity in male urethra and the acidity of the vagina
- produces 5% of semen
Describe the contents of prostate gland secretions and its contribution to the overall volume of seminal fluid
- Secretions contain proteolytic enzymes
- Contributes to 25% of seminal fluid
What is the usual size of the prostate?
- Walnut
- 2-4 cm
Which part of the prostate gland is felt on rectal examination?
Peripheral zone
Enlargement of which part of the prostate causes urethral obstruction?
Transitional zone
Describe the venous drainage of the prostate gland
- Blood drains via prostatic venous plexus which drains into the internal iliac veins
- This connects posteriorly to the vertebral venous plexus
Which part of the urethra is least distensible (capable of being extended0?
Membranous urethra
Name the erectile tissue in the penis
- Corpora cavernosa
- Corpus spongiosum
Identify possible causes of scrotal swelling
- Orchitis
- Infections
- Hernia
- Hydrocoele
Generally, how can one discriminate between a hernia and a testicular swelling?
Hernias change with position
What is a hydrocoele?
Hydrocoele is a collection of serous fluid in the tunica vaginalis
What is a haematocoele?
Haematocoele is a collection of blood in the tunica vaginalis
How can one distinguish between a haematocoele and a hydrocoele?
- Transillumination (light is applied to testicular swelling)
- Due to dense nature of blood, light is unable to pass through
What is a varicocoele?
Varicocoele is the gross dilation of veins draining the testes
Why is the left testicle commonly affected in varicocoele?
- Left testicular vein drains into the left renal vein at a 90o angle
- Renal vein is smaller than IVC and there is no valve, building up pressure
What does a varicocoele look and feel like upon palpation?
A bag of worms
How can you prevent a testicle from becoming twisted again
place a suture in and keep in it place
testiuclar blood supply
- artery: arises form the abdominal aorta, inferior to the SMA, and superior to the IMA
- veins: pampinform venous plexus
how does the body regulate a cold temperature in testicles for sperm to be made
- vein forms plexus around the artery
- vein carries cold blood up (from testies) which cool the blood in the arteries
- the cooler blood from the arteries will now supply the testies
- => countercurrent
how does the body regulate a cold temperature in testicles for sperm to be made
- vein forms plexus around the artery
- vein carries cold blood up (from testies) which cool the blood in the arteries
- the cooler blood from the arteries will now supply the testies
- => countercurrent
identify the “3 others” that are found within the in the spermatic chord
- The VAS
- lymphatics
- patent process vaginalis but this soon gets obliterated
what does the saying water under the bridge mean
ureter runs under the vas
which is the erectile tissue in the penis
- corpus cavernosum
label this cross section of the penis
tunica albuginea
‘aubergine’
- gives the penis the circular shape
- divides the testies into separate sections called lobules
- can get swollen
what is the function of the epididymis
- where the sperm become mobile
- sperm are stored here until ejaculation
- connected to the VAS where sperm get transported
what is the role of the seminal vesicles
- produces 70% semen
- proteins, fructose, glucose
what is the ejaculatory duct
where the seminal vesicle meets the ductus deferents at the prostate
- empties into the prostatic part of the urethra
what is the difference examining a hernia and a hydrocele
- you can only feel the other side of the hernia as the rest of the bulge is within the inside of the bowel
- A hydrocele is a fluid mass of which you can feel all of it and see all of it
what is the role of the internal urethra sphincter
to prevent back flow of semen into the bladder
