URINARY: EMBRYOLOGICAL DEVELOPMENT Flashcards
Uroginital system is derived from which mesenchyme?
Intermediate mesenchyme.
urogenital system divides into which systems?
genital and urinary
During longitudinal elavation what forms on either sides of the dorsal aorta?
urogenital ridges
and part of the ridges form -NEPHROGENIC CORD.
Name the three set of successive kidney development
- pronephroi
2.mesonephroi
3.metanephroi
explain the first set
Represented by a few cell clusters and tubular structures in developing neck region
Pronephric ducts run caudally and open into cloaca (where hindgut and allantois empty)
Pronephroi soon degenerate
Most parts of ducts persist – used in second set of kidneys
second set fully functions when?
during fetal stage.
Large, elongated excretory organs
appers when ?
in the msenophroi set and in week 4 cadual to pronephroi.
what does mesonophroi consist of :
1.Glomeruli
2.mesonephric tubules- drain into mesonophric duct whoch open into cloaca.
Function as interim kidneys for ~ 4 weeks, until permanent kidneys develop and function
Degenerates towards end of 12th week; however, mesonephric ducts have adult derivatives
The third set forms permanent kidney
> Matanephroi
begin development in the 5th week but fully functional 4 weeks later or just in week 9.
The kidney develops from which sources ?
> The ureteric bud
Metanephrogenic blastema
The ureteric bud
start as outgrowth(metanephric dirveticulum), from mesonephrenic duct near entrance into cloaca.
Metanephrogenic blastema.
> Metanephric mass of mesenchyme
Derived from caudal part of nephrogenic cord.
later on the ureteric bud becomes incorporated with the Blastema
The stalk of the ureteric bud becomes what?
Ureter
The cranial part of the ureteric bud undergoes branching and results into ……….
Collecting tubules
what forms from the first 4 generation of tubules
enlarge, become confluent and form major calices
What forms from the second 4 generation of the tubules.
merge to form minor calices.
end of the arched collecting tubules induces clusters of mesenchymal cells to form what.
Metanephric vescles.
Metanephric tubules
formed by elongated metanephric vesicles.
The tubules differentiate into what structures?
Proximal, and distal convoluted tubules, loop of Henle, glomerulu and glomerular capsule
Nephron formation.
complete at birth
and no nephron formed after birth
Relation of the primordial permanent kidney.
Ventral to sacram
During the beginning of the feotal period what event takes place?
Kidneys adult position
Which event needs to occur to form nephron
formation of the ureteric bud and blood supply from theblastema.
During which week does the kidney faces anteromedial direction?
WEEK 9
the space between the urinary and genital system is called ?
Urogenital sinus
The urogenital space is divided into 3 parts?
1.Vesical part: forms urinary bladder, continuous with allontois
- pelvic part: becomes urethra in neck of bladder, prostatic part of urethra in males and entire urethra in females
- Phallic part: grows towards genital tubercles.
The urogenital space is divided into 3 parts?
1.
Primordium of penis and clitoris.
genital tubercle.
bladder develops from ??
endoderm of the vesical part of the urogenital sinus
Initially bladder is continuous with allantois; however, this soon becomes what?
A thick and fibrous cord called urachus.
Urachus extends from the Apex to where?
Umbilicus.
The urachus in adults is represented by what ?
median umbilicus ligament.
What contribute to the formation of the connective tissue in Trigone of the bladder.
Distal parts of mesonephric duct are absorbed into the distal wall
The urethra of the female and male is derived from
endoderm of the urogenital sinus.
what is derived from ectodermal cells?
THE distal part of urethra in glans penis.
Epithelium of terminal part of urethra is thus derived
surface ectoderm.
Connective tissue and smooth muscle of urethra derived
splanchnic mesenchyme
Cortex of suprarenal gland
– from mesenchyme of urogenital ridge
Medulla of suprarenal gland
derived from the neural crest cells
Renal Agenesis
Absence of kidney
Unilateral renal agenesis
> Having one kidney.
> usually not discovered in infancy since the other kidney undergoes compensatory hypertrophy to perform function of missing kidney
Bilateral renal agenesis
associated with oligohydramnios, a condition that develops since little/no urine is excreted into amniotic cavity.
