Flashcards in Embryology Deck (58)
What germ layer/structure forms the kidney ?
Where is the intermediate mesoderm located ?
Just lateral to paraxial mesoderm adjacent to the somatic mesoderm
Paraxial mesoderm will go on to form all of the skeletal muscle
What are the main functions of the kidney ?
Electrolyte balance, Acid/base Regulation, Hematopoiesis
What is the functional unit of the kidney ?
Structurally, what is a glomerulus ?
An arterial capillary bed (tufted capillary bed)
Where does the external glomerulus (early structure) empty ?
It empties into the structure that will become the peritoneal cavity
What are the three phases of kidney development that form from intermediate mesoderm?
Pronephros (Proximal) Early
Mesonephros (Medial) Middle
Metanephros (Distal) Late
When will the pronephros form ?
First of the structures to form (3-4 weeks)
Will eventually regress
When does the Mesonephros form ?
When will the metanephros form ?
The mesonephros functions as the kidney for a short while, creating embryonic urine. Where do the excretory tubules from this structure empty into ?
Wolfmann's Duct (Mesonephric duct). This structure will eventually empty in to the Cloaca.
Later in development the Ureteric bud will come off of this structure.
The distal end of the tubules from the mesonephros will form what structure ?
Bowmens capsule (it will become associated with capillary beds to achieve this )
Due to the mesonephros' ability to create urine it damage to it can contribute to pathologic disease. Define oligohydraminos ?
Too little amniotic fluid
Often associated with renal developmental defects that lead to decreased urine production (fetal urine is a constituent of amniotic fluid)
Define polyhydraminos ?
Too much amniotic fluid.
Often associated with 'drinking' deficiencies in the fetus like esophageal atresia
What is the structure called that is a part of the mesonephros and will lead to the development of the gonad ?
Urogenital Ridge (medial side of the mesonephros)
What occurs to the mesonephric duct in females ?
Nothing very significants , degenerates
What might occur if there is improper development/degeneration of the mesonephric duct in females ?
Gardners Cyst (fluid filled cysts in the bladder or vagina)
What occurs to the mesonephric duct in males ?
Becomes the part of the male reproductive tract (Ductus deferens, maybe more ?)
What important structure come of of the mesonephric duct to help form the kidney in conjunction with the metanephric mesoderm ?
The Ureteric Bud
What does the ureteric bud form in the kidney ?
Invades the metanephric mesoderm
Forms kidney tubules, collecting ducts ant ureters. (dilates and forms the primitive renal pelvis, calyces and the collecting tubules.)
What does the metanephros (metanephric blastema) give rise to ?
THE NEPHRONS ! (The invasion of the ureteric bud cause the metanephros to differentiate)
What do the glomeruli arise from ?
Mesenchyme (vascular mesoderm)
How does the kidney rotate as it Ascends from the pelvis into the abdomen ?
Rotates interiorly so that the renal pelvis is medial
What occurs to the lobules as the kidney matures ?
They smooth out
what is the cloaca
common opening for feces and urine (female Reproductive as well)
what is the allantois ?
growth off of the endoderm, stalk derived from the cloaca
where does the urinary bladder form from
What does the allantois become once the mature GU system forms ?
Median umbilical ligaments.
What ind of tissue forms the trigone ?
It is surrounded by endoderm however.