T2 L13: Anatomy of the male reproductive tract Flashcards
What is the SRY gene for?
It initiates the development of a male baby.
It causes cells within the gonad to develop into Sertoli cells
Without this gene functioning, there won’t be any testicular development
Which duct does the ductus deferens develop from?
The mesonephric duct
Under the influence of the SRY gene, the duct stays to carry sperm but degenerates in women
What does the gubernaculum do?
It leads the testes while they descend
When testes descend, do they cross the ureter?
Yes
At what age do testes begin to descend?
At 12 weeks. By week 32 they arrive in the scrotum
Which artery supplies the testes?
The testicular artery
Which vein drains the testes?
Veins from the pampiniform plexus
Which nerve innervates the testes?
The spermatic plexus
What is the function of the seminiferous tubules?
They are coiled tubules where sperm is produced
What is the function of epididymis?
To transport and store sperm
Why is the vas deferens surrounded by smooth muscle?
To allow for ejaculation
Describe the structure of seminiferous tubules
Highly tortuous and lined by a seminiferous epithelium
They’re surrounded by stroma, loose connective tissue
Why do Sertoli cells enfold developing spermatozoa?
- Protect them from blood antibodies
- Provide nutrients
- Phagocytose excess cytoplasm
- Secrete androgen binding protein
- Secrete inhibin
- Add fluid to the lumen
Between which layers does an inguinal hernia occur?
Between the deep and superficial inguinal rings
What goes through the inguinal canal in men?
Ductus deferens
Testicular artery and vein
Nerves
Does the round ligament go through the inguinal canal in men?
No. The round ligament develops into the vas deferens in men
The round ligament goes through the inguinal canal in women
What % of inguinal hernias affect men?
98%
What is a patent processus vaginalis (PPV)?
It allows a communication between the peritoneum and scrotum. It typically presents as hydrocele
What is the function of the cremaster muscle?
It moves the testes to suit the temperature (Closer if it’s cold and lower when its warm)
Which VAN supply the ductus deferens?
Inferior vesical and middle rectal
What do seminal vesicles secrete?
Alkaline fluid, fructose, and coagulate
What does the prostate secrete?
Prostatic fluid (20% of total fluid)
What do bulbourethral glands secrete?
Lubricants for the ducts
Where are seminal vesicles found?
The posterior aspect of the bladder
What is the nerve supply the seminal vesicles?
Sympathetic and causes ejaculation
Which veins and arteries supply the seminal vesicles?
Inferior vesicle and prostatic vessels
Which veins and arteries supply the prostate?
Prostatic veins and arteries
Which nerves supply the prostate?
Inferior hypogastric and parasympathetic from the pelvic splanchnic nerves
Where are bulbourethral glands found?
In the external urethral sphincter
Which veins and arteries supply the bulbourethral glands?
Inferior vesicle and prostatic vessels
What is the superficial perineal pouch?
A space between the perineal fascia and the perineal membrane
What does the superficial perineal pouch in men contain?
The root (bulb and crura) of the penis Ischiocavernosus Bulbospongiosis Urethra Superficial transverse perineal muscle Pudendal vessels
What does the superficial perineal pouch in women contain?
Clitoris Ischiocavernousus Bulb of vestibule (bulbospongiosis) Greater vestibular gland Urethra Superficial transverse perineal muscle Pudendal vessels
What does the deep perineal pouch contain in men?
Bulbourethral glands Dorsal neurovascularture of the penis Urethra and external urethral sphincter Ischioanal fat pads Deep transverse perineal muscle
What does the deep perineal pouch contain in women?
Dorsal neurovasculature of the clitoris
Urethra and external urethral sphincter
Ischioanal fat pads
Deep transverse perineal muscle
Which parasympathetic nerves supply the perineum?
Pevic splanchnic nerves (S2-4)
Which sympathetic nerves supply the perineum?
Sacral sympathetic trunk
Superior and inferior hypogastric plexuses
Which nerves does the pudendal nerve give rise to?
Inferior rectal
Perineal branches
Posterior scrotal/labial
Dorsal nerve to the penis/clitoris
Which nerve supplies the anterior scrotum?
The hypogastric nerve
At which gestation do external genitalia begin to develop?
At week 3
What happens to external genitalia development without androgens?
The genital tubercle elongates only slightly to form the clitoris and the urethral folds form the labia minora
What is the penile raphe?
It’s the line where the scrotal swellings fused during development to create a penis
What are the 3 cylindrical bodies of the penis?
Paired corpora cavernosa and 1 corpus spongiosum
Which nerves supply the penis?
S2/4 pudendal nerve, dorsal nerve to penis, and ilioinguinal nerve
Which veins and arteries supply the penis?
The internal pudendal arteries and external pudendal veins
What encapsulates the cavernous bodies of the penis?
A tough fibrous sheath called the Tunica Albuginea
What are the 3 divisions of urethra in men?
Prostatic, membranous, and penile
What is the prostatic utricle?
The remains of what could have developed if they were female
What is cryptorchidism?
Undescended testes
What is a hematocele?
A collection of blood within the scrotum
What is an orgasm in men physiologically?
A contraction of the bulbospongiosis muscle
