Repro 1: Development Of Reproductive Systems Flashcards
In males, Sertoli cells express which gene?
The SRY gene (on the Y chromosome)
This drives development of the make gonad, internal genatalia, and external genitalia
Male internal genitalia is formed by…
Mesonephric ducts aka Wolffian duct
Female internal genitalia is formed by…
Paramesonephric ducts (aka Müllerian ducts)
In males, how do the Müllerian ducts regress?
Sertoli cells secret MIH (müllerian inhibitory hormone) and interstitial cells secrete testosterone
Hence, Müllerian ducts regress and Wolffian ducts develop
If there were no gonads at all, which ducts would develop?
Müllerian ducts
In female, what do the urethral folds and genital swellings form?
Genital folds form labia minora
Genital swellings forms labia majora
In females, what does the gentian tubercle form?
Clitoris
In males, what does the gentian tubercle form?
Glans penis
Forms under stimulation from androgens, unlike female genitalia which forms without hormonal stimulation
In males, what do the genital folds form?
They fuse to form spongy urethra and shaft of the penis
In males, what do the genital swellings forms?
They fuse to form the scrotum
Before the testes descend, what attaches them to the future scrotum?
Gubernaculum
Failure of what to obliterate in males will cause an indirect inguinal hernia?
Failure of processes vaginalis to obliterate
What is the fascial layer that covers the testes as they descend?
Processus vaginalis
What is the remnant of the gubernaculum in men?
Scrotal ligament
In females, the gubernaculum attaches the ovaries to the labioscrotal folds. What does the gubernaculum later become?
The ovarian ligament, attaching the ovaries to the uterus
What is the only structure occupying the inguinal canal in females?
Round ligament of the uterus (attaching uterus to labia)
What are some characteristics of Turners syndrome (45,XO)?
Short stature
Primary amenorrhoea
Failure of secondary sexual characteristics eg breasts
What do Leydig cells secrete?
Androgens, mainly testosterone
Where do spermatozoa develop?
In seminiferous tubules, in association with Sertoli cells
Initially, spermatogonia divide by mitosis to give rise to which 2 cell types?
Type A spermatogonia which are stem cells to maintain the stock
Type b spermatogonia which are committed to differentiation to produce primary spermatocytes
What happens to the primary spermatocytes in spermATOgenesis?
They undergo meiosis to form 2 haploid spermatocytes
These divide again to form 4 primary spermatids
What happens in spermIOgenesis?
The spermatids differentiate into spermatozoa. Cytoplasmic bridges break down and the sperm is released into the lumen
What structures do sperm pass down as they are produced?
Seminiferous tubules -> rete testis -> ductuli efferentes -> epididymis -> vas deferens -> urethra
What is the point in the blood testes barrier?
To stop the immune system getting access to the spermatozoa