Embroylogy Of The Urianary System Flashcards
Where do the kidney systems form from?
The intermediate mesoderm
What are the 3 stages of the development of the kidney?
Pronephros, mesonephros and metanephros
When does the pronephros develop?
Forms at the start of the 4th week, and has disappeared again by the end of the 4th week
What are some of the features of the pronephros?
Never functions in humans and is described as a duct, which extends from the cervical region to the cloaca and drives the next developmental stage
What is the urogenital ridge?
A region of intermediate mesoderm giving rise to both the embroyonic kidney and the gonad
What are some of the features of the mesonephros?
It is formed in the pronephric region, is derived from the intermediate mesoderm in the upper thoracic and lumbar regions, and appears in the 4 th week of development during the regression of the pronephric system
How does the mesonephros develop?
Lengthens rapidly, forms a s shaped loop and aquires a tuft of capilleires that will form the glomerulus at their medial extremity and around the golomeukus the tubules in the bowman’s capulse and therefore the renal corpuscle
What happens in the mesonephric duct?
Sprouts the urogentital bud which induces the development of the definitive kidney, and has an important role in the development of the reproductive system.
What are some of the features of the metanephros?
The utreic bud induces the development of the definitive kidney within the intermediate mesoderm of the caudal region of the embryo,p.
What is the uteric bud?
Is an outgrowth of the mesonephric duct close to the entrance of the cloaca
What happens to the uteric bud?
The bud penetrate the metanephric tissue, Nd divides to form the primitive renal pelicis, and forms tubules which form the calcyes of the kidney, and this gives rise to the ureter, the renal pelvis and the major and minor calcyes
What is the importance of the uteric bud?
The uteric bud drives the development of the definitive kidney, and the excerterory component is derived from the intermediate mesoderm under the influence of the uteric bud
What is the ascent of the kidney?
The metapnepheic kidney first appears in the pelvic region, and undergoes an apparent caudal to cranial shift and crosses the atreial fork formed by the vessels returning blood from the featus to the placenta
What causes the ascent of the kidney?
It is caused by a dimmunation of the body curvature and by the growth of the body in the lumbar and the sacral regions,
What happens to the blood supply of the kidney during its ascent?
In the pelvis the metanephros receives its blood supply from a pelvic branch of the aorta, and during its ascent to the abdominal level, it is vascularised by ateries that originate form the aorta at continously higher levels, and the lower vessels commonly degenerate .