hi:development-of-urogenital-system

Urogenital System

Genital ridge	जननांग कटक
Genital tubercle	जननांग स्थूलक
Mesonephric duct - wolfian duct	आद्य-मध्यवृक्क
Mesonephric tubules	आद्य-मध्यवृक्क
Metanephros	पश्चवृक्कप्रसू
Metanephros blastema	पश्चवृक्कप्रसू
Metanephros vesicle	पश्चवृक्कप्रसू
Nephrogenic cord
Paramesonephric duct	आद्य-परामध्यवृक्क
Ureteric bud	आद्य मूत्रवाहिनी कलिका
Urogenital membrane	आद्य मूत्रजनांग झिल्ली
Urogenital ridge	आद्य मूत्रजनांग कटक
Urorectal septum	मूत्रमलाशय पट्ट
Uterovaginal canal	मूत्रयोनि नाली
Vesicourethral canal	पुटिकामूत्रमार्ग नली
Primitive urogenital sinus	आद्य मूत्रजननांग विवर
Primitive renal tubule	आद्य नली

Intermediate Mesoderm extends on each side of primitive dorsal aorta
- bulging on posterior abdominal wall lateral to dorsal mesentery
- आद्य मूत्रजनांग कटक ( urogenital ridge )
  - Lateral Nephrogenic Cord
    - extends from cervical to thoracic segments , each segment called nephrotome
    - rest of unsegmented column , known as nephrogenic cord
    - development and dissapearnace ( ONTOGENY REPEATS PHYLOGENY )
      - firstly propnephros ( upper cervical and thoracic segments )
        
        pronephros dissapears except its duct
        
        from Solid cellular cord of cells
        
        acquires a lumen called as nephrocele
        
        evagination from dorsal wall
        
        grows laterally and then caudal backwards
        
        downturned ends join to form single primary excretory or pronephric duct
        
        bends in to urorectal septum
        
        opens in to ventral part of cloaca
        
        other end is present close to peritoneal funnel
        
        external glomerulus of capillaries project in to dorsal wall of coelom
        
        internal glomerulus
        
        metabolic wastes are liberated through these
        
        7-8 segmentally arranged pronephric tubules
      - Secondly mesonephros ( thoraco-lumbar direction )
        
        cephalic part of mesonephros dissapears
        
        caudal part shifts alleigance to genital system
        
        in males it forms the duct system of testes
        
        in females it forms part of broad ligament
        
        70-80 Mesonephric tubules appear serially
        
        laterally opens in to pronephric duct
        
        mesonephric duct or wolffian duct
        
        medial end does not communicate with coelomic cavity
        
        internal glomerulus by a dilated blind end
        
        mesonephric tubules become S-shaped
        
        medial secretory part lined by columnar cells
        
        lateral collecting part lined by cuboidal cells
        
        each segment contains one mesonephric tubule and one glomerulus
        
        tracing caudally each contains 3 or more tubules
        
        each tubule is connected to numerous glomeruli
        
        proximal mesonephric tubules start disappearing around 5 th week
        
        ureteric bud develops from the mesonephric duct
        
        its distal end dilates and invades nephrogenic cord
        
        it shifts from dorsomedial to dorsolateral side
        
        cap like investment called metanephric blastema
        
        distal dilated end divides in to cranial and caudal parts
        
        future major calyxes
        
        the main duct connecting ureteric bud and mesonephric duct to cloaca is called
        
        common excretory duct
        
        around 8 th week 26 tubules and a single duct persist
      - Thirdly metanephric blastema ( lumbo-sacral region )
        
        retained as the permanent kidney
  - मध्य जननांग कटक ( Medial Genital Ridge )
Cloaca
- आद्य मूत्रजनन गुहा (Primitive urogenital sinus)
  - vesico-urethral canal
    - urinary bladder
    - primitive urethra
- निश्चित मूत्रजनांग गुहा ( Definitive urogenital sinus )
  - pelvic part
  - phallic part