Summary
chapter 19 summary Junqueira's Basic Histology
chapter 19 summary Junqueira's Basic Histology
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
Content preview
UROGENITAL SYSTEM● Development of the urinary and genital systems is intimately associated.
● The urinary system develops before the genital system.
● Three successive kidney systems develop: pronephroi (nonfunctional), mesonephroi (temporary excretory
organs), and metanephroi (primordia of permanent kidneys).
● The metanephroi develop from two sources: the ureteric buds, which give rise to the ureter, renal pelvis,
calices, and collecting tubules, and the metanephrogenic blastema, which gives rise to the nephrons.
● At first, the kidneys are located in the pelvis; however, they gradually shift position to the abdomen.
This apparent migration results from disproportionate growth of the fetal lumbar and sacral regions.
Gonadal sex is determined by testes-determining factor, which is located on the Y chromosome.
Testes determining factor directs testicular differentiation.
The interstitial cells (Leydig cells) produce testosterone, which stimulates development of the
mesonephric ducts into male genital ducts. Testosterone also stimulates development of the
indifferent external genitalia into the penis and scrotum.
MIS, produced by the Sertoli cells, inhibits development of theparamesonephric ducts (primordia of
the female genital ducts).
● In the absence of a Y chromosome and the presence of two X chromosomes, ovaries develop, the
mesonephric ducts regress, and the paramesonephric ducts develop into the uterus and uterine tubes.
The vagina develops from the vaginal plate derived from the urogenital sinus, and the indifferent
external genitalia develop into the clitoris and labia majora and minora.
● Persons with ovotesticular DSD have both ovarian & testicular tissue & variable int. & ext. genitalia.
In the 46, XY disorder of sex development, the fetal testes fail to produce adequate amounts of
masculinizing hormones or there is tissue insensitivity of the sexual structures.
In the 46,XX disorder of sex development, the cause is usually congenital adrenal hyperplasia, a
disorder of the fetal suprarenal glands that causes excessive production of androgens and
masculinization of the external genitalia.
● Most defects of the female genital tract, such as double uterus, result from incomplete fusion of the
paramesonephric ducts. Cryptorchidism and ectopic testes result from abnormalities of testicular descent.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller OGN. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for CA$10.76. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
81113 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now