Changes

 

==Introduction==

==Introduction==

The intermediate mesoderm exists as a strip of tissue between the lateral plate mesoderm and somites. It gives rise to the urinary system and some parts of the reproductive system. Kidney development includes three forms:

The intermediate mesoderm exists as a strip of tissue between the lateral plate mesoderm and somites. It gives rise to the urinary system and some parts of the reproductive system. Kidney development includes three forms:

==Pronephros==

==Pronephros==

*''The earliest kidney. Develops in the anterior of the animal (adjacent to somites 7 - 10). Eliminated in later development''.

*''The earliest kidney. Develops in the anterior of the animal (adjacent to somites 1 - 10). Eliminated in later development''.

#At intervals along the intermediate mesoderm, dorsal evaginations occur.

#At intervals along the intermediate mesoderm, dorsal evaginations occur.

#Evaginations extend caudally and eventually fuse with more caudal evaginations.

#Evaginations extend caudally and eventually fuse with more caudal evaginations.

==Mesonephros==

==Mesonephros==

*''Development occurs in an anterior to posterior direction; the mesonephros kideny is found at the thoracic to lumbar level''.

*''Development occurs in an anterior to posterior direction; the mesonephros kidney is found at the thoracic to lumbar level''.

#The medial portion of the intermediate mesoderm forms a cup in the region of the capillaries.

#The medial portion of the intermediate mesoderm forms a cup in the region of the capillaries.

#*This is an early Bowman's capsule and improves waste removal.

#*This is an early Bowman's capsule and improves waste removal.

#*Excretory duct now known as the '''Wolffian Duct'''.

#*Excretory duct now known as the '''Wolffian Duct'''.

*Amphibians and fish use the mesonephric kidney.

*Amphibians and fish use the mesonephric kidney.

==Metanephros==

==Metanephros==

#*It subsequently develops into a nephron.

#*It subsequently develops into a nephron.

#The remaining branch splits into two, and repeats the process.

#The remaining branch splits into two, and repeats the process.

 

 

[[Category:Developmental Biology]]

 

[[Category:Urinary System - Anatomy & Physiology]]

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