Development of the urinary tract AHS1 Flashcards
What embryological structure is most of the urogenital tract derived from?
The intermediate mesoderm at the urogenital ridge
What is the epithelial lining of the bladder and urethra derived from?
The endoderm because they come from the end of the hindgut
What is the cloaca?
The end of the digestive, urinary and reproductive tracts where they all come to the same point
What are the 3 stages of kidney development?
Pronephros (v short)
Mesonephros (fish stop here)
Metanephros
What develops in pronephros?
The pronephric tubule (non functional)
A duct to the cloaca
Where does the kidney initially develop in pronephros?
In the cervical (neck) region
Where does the mesonephros develop from?
The urogenital ridge in the thoracic and lumbar region
What occurs during metanephros?
The mesonephros develops a simple nephron structure
Blood vessels invade from the aorta
What happens to the mesonephros in most animals?
It will be replaced by the third stage kidney (metanephros)
What is the duct called in mesonephros?
The mesonephric duct
Where does the majority of the metanephric kidney develop from?
The urogenital ridge in the lumbar region
Where does the ureter develop from?
The ureteric bud that comes off the mesonephric duct
What parts of the kidney are derived from the mesonephros?
Ureter
Renal pelvis
Calices
Collecting ducts
Where does the kidneys capillaries come from?
Invaginations from the renal artery
What type of kidney is initially made?
Multipyramidal
What embryological layer is the bladder formed from and why?
The endoderm because it is formed from part of the gut tube
What is the urorectal septum?
It divides the urinary tract/bladder from the digestive tract/rectum
Means there are two holes
What is the bladder formed from?
The allantoic bud
In what animals does the cloaca remain as one chamber?
Birds and reptiles
What does the caudal part of the allantoic bud form?
The urethra
What does the central part of the allantoic bud form?
The bladder
What does the cranial part of the allantoic bud form?
The urachus
What is the urachus?
It allows the foetus to remove urine into the surrounding sac
It closes in later development
What are the non-epithelial parts of the urinary tract derived from?
The splanchnic (meaning visceral) lateral plate mesoderm
