Development of Urogenital system Flashcards
Urogenital system develops what 2 systems?
Urinary system
Genital system
Both the Urinary and Genital system develop from what common germ layer?
Intermediate mesoderm
The intermediate mesoderm runs from head to tail but has two different types or qualities. What are they?
Segmented intermediate mesoderm
Unsegmented intermediate mesoderm
Segmented intermediate mesoderm is the precursor to what?
Pronephros
The unsegmented intermediate mesoderm is the precursor to what two tissues?
mesonephros and metanephros
During fetal life, kidney systems develop through three developmental stages: (progresses from cranial-to-caudal). What are they?
- Pronephros
- Mesonephros
- Metanephros
Ruidmentary and nonfunctional. Comes from the segmented intermediate mesoderm
Pronephros
May function for a short time during early fetal period
Mesonephros
Forms the permanent kidney
Metanephros
What is the future urinary bladder?
Allantois
a primitive duct that collects the excretion from the mesonephros is called what?
Wolffian Duct
lengthen to form a S-shaped loop
excretory tubules ( development of the mesonephros)
The medial end of each of excretory tubule acquires a tuft of capillaries (branch from aorta) to form a _________?
glomerulus
Around the glomerulus, the excretory tubule forms the ______________, and together these structures constitute a ____________.
Bowman’s capsule; renal corpuscle
Each tubule joins the longitudinal collecting duct known as the ????
mesonephric duct/ Wolffian duct
MEtanephros starts with the development of the ?????
Ureteric bud
The uteric bud grows and pushes into the unsegmented intermediate mesoderm tissue in the region, called the ?????
metanephric blastema
The ureteric bud will give rise to the _______, __________, __________, collecting duct, and collecting tubule. But the PCT –Loop of Henle- DCT- Bowman’s capsule (parts of the nephron come from the Metanephric blastema tissue
ureter
major calyces
minor calyces
Each collecting tubule is covered by a ___________
metanephric tissue cap
Under influence of the collecting tubule, cells of the metanephric tissue cap form renal vesicles, which then turn into small ____________
S-shaped tubules
The PCT, Loop of Henle, DCT, & Bowman’s capsule come from the ___________
Metanephric blastema tissue
Recall the difference between a Nephron and a uriniferous tubule. The Parts of the Nephron originate from the __________, but the Collecting ducts, etc.. originates from the ________
metanephric blastema; ureteric bud
The S-shaped tubules turn into a ________
Nephron
Capillaries grow into the pocket at one end of the S-shaped tubule and differentiate into ________
glomerulus
Proximal end of each nephron forms the _______________.
The distal end of this tubule joins the collecting tubules.
Bowman’s Capsule.
The kidney is initially in the caudal region. Later it shifts ____________
upwards into the abdomen
The urogenital sinus develops into what?
Urinary bladder
Initially, the bladder is continuous with the allantois.
Later the lumen of the allantois is blocked by a thick fibrous cord called the ????
the urachus
The ductus deferens originates from what tissue?
Mesonephric/wolffian duct
The __________ of urogenital sinus is a narrow canal. In males, this gives rise to the prostatic urethra.
pelvic part
The distal part is called the _________ of the urogenital sinus. As the genitals grow, this part will grow ventrally to give rise to the penile urethra
phallic part
Sexual dimorphism is dependent on the ____________
Y chromosome
Y chromosome contains the SRY gene (Sex- determining Region on Y gene) aka the __________
testis-determining gene
The protein product of SRY gene is a transcription factor that initiates a cascade of transcription of many downstream genes that causes ‘______________’ to develop into testis
the indifferent gonad
First appearance of gonads is as a pair of longitudinal ridges called the
genital ridges
The genital ridges originate from the underlying __________
mesenchyme and surrounding epithelium
Medullary cords develop in ___________ and degenerate in ___________
Males; Females
Females have development of _____________ while males do not develop them due to the SRY Gene.
Cortical cords
SRY gene codes for testis-determining factor. It signals the genital ridge to differentiate into the _____________
Medullary cords/Testis cords
In the absence of SRY gene the genital ridge tissue dissociates into cell cluster. These form the ___________
Coritcal cords
Cells from cortical cords contribute to the formation of ________
primordial follicles