Embryology Flashcards
When does organogenesis usually take place?
During weeks 3-8 mainly
What other system is the urinary system related to?
Reproductive and urinary systems have close embryological links and some of these associations carried into adulthood both in relation to the normal individual and in some anomalies of the urogenital system
Urinary system forms template for reproductive system development
What are the constituents of the adult kidney?
Renal pelvis
Calyces
Uriniferous tubule
- Nephron
- Collecting duct
What are the constituents of the adult urinary system?
Kidneys
Ureters
Urinary Bladder
Urethra - male and female
Blood supply- L1 Aorta
What components make up the nephron?
Renal corpuscle
Proximal convoluted tubule
Loop of Henle
Distal convoluted tubule
What makes up the uriniferous tubule?
Nephron
Collecting duct
When does gastrulation occur?
3rd week
What is gastrulation?
Bilaminar to trilaminar disc
Three primary “germ” layers of all body tissues develop from these:
- Ectoderm
- Mesoderm
- Endoderm
What does the mesoderm divide into early on?
Paraxial mesoderm
Intermediate mesoderm
Lateral plate mesoderm
The urinary system develops from?
Intermediate mesoderm
-Kidney and ureter
Cloaca
-Urinary bladder and urethra
What does the urogenital ridge form from?
Intermediate mesoderm forms longitudinal ridge along the embryo called the urogenital ridge/cord
What does the urogenital ridge/cord form?
Partitions into a nephrogenic ridge/cord and a gonadal ridge/cord
Why is the entire urinary system retroperitoneal in the adult?
Urogenital ridge covered in front with coelomic epithelium (peritoneum)
What structures make up the nephrogenic ridge?
Paramesonephric duct
Mesonephric duct
Mesonephros
Gonad
What does the paramesonephric duct form?
Forms uterus and uterine tubes
What does the mesonephric duct form?
Drains primitive kidney but later forms ductus deferens
What does the mesonephros form?
Is early embryonic functioning kidney
Are excretory tubules that largely disappear
Function taken over by metanephros (caudal to mesonephros)
What does the gonad form?
The gonads (testes/ovary)
What 3 sets of kidneys develop in the embryo?
Pronephros
Mesonephros
Metanephros
What does the mesonephric duct open into?
What does it give off?
Mesonephric duct opens into the cloaca
Gives off the uteric bud
Does the urinary system or the reproductive system develop first?
Urinary system