Urogenital Development Flashcards
1
Q
What predominately form the urogenital system
A
Intermediate mesoderm
2
Q
What are the 3 regions of the urogenital system
A
- Pronephros
- Mesonephros
- Metanephros
3
Q
Pronephros
Arrangement
From
A
- Segmentally arranged cords (nephrotomes)
- Anterior intermediate mesoderm
- Connected by pronephric ducts
- Degenerates early
- Non functional
- May concentrate urine but there arent any ducts to secrete it
4
Q
Mesonephros
Composed of what
A
- Glomerulus surrounded by capsule
- Meonephric tubule extends toward capillary bed from mesonephric duct
- Similar to aquatic animal filter
*
5
Q
Mesonephric Duct
Primary orientation, stimulate, becomes
Diff between females and males
Develops
A
- Primary mesonephric ducts
- Extend caudually (next to somites)
- Stimulate formation of mesonephric tubules
- Becomes mesonephric (Wolffian) duct
- Attach to cloaca
- Regress in females
- Remain in males (ductus deferens)
- Develops uteric bud
6
Q
Metanephros
A
- Uteric bud grows into posterior intermediate mesoderm
- Elongates and branches, becoming collecting duct system
- Metanephric blastema
- cells surrounding metanephric duct (excretory portion)
7
Q
Uteric bud bifurcations
A
- tip of first ampulla gives rise to renal pelvis
- Uteric bud bifurcates 4 times, 16 branches, which coalesce to form calyces
- Mino calyces are also formed
- will form future collecting tubules and ducts
8
Q
Migration of kidney
A
- Pelvic to lateral abdominal
- Come in contact with adrenal glands
9
Q
Formation of urinary bladder
A
- Urogenital sinus continous with allantois
- Base of allantois forms bladder
- Bladder incorporates mesonephric duct and uteric buds
10
Q
Male Sexual duct differentiation
A
- Sertoli cells secrete Mullerian Inhibiting factor
- Paramesonephric ducts degenerate
- Testosterone stimulates mesonephric ducts to continue to develop
- Ductus deferens
11
Q
Female Sexual Duct Differnetiation
A
- Absence of Mullerian Inhibitory factor or testosterone
- Mesonephric ducts degenerate
- Paramesonephric ducts continue to develop as oviducts
12
Q
Indifferent External Genitalia
A
- Genital tuburcle (tip)
- Genital folds (shaft)
- Urogenital sinus (lips)
- Urethral plate
- Genital swellings (aouond base of shaft)
13
Q
Male External Genitalia
A
- Influenced by DHT
- Genital tuburcle elongates–> penis
- Genital Swellings–> scrotal pouch
- Genital folds fuse closing
