Difference between revisions of "Intermediate Mesoderm Development - Anatomy & Physiology"
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(New page: <big><center>'''BACK TO DEVELOPMENTAL BIOLOGY</center></big>) |
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<big><center>[[Developmental Biology - Anatomy & Physiology|'''BACK TO DEVELOPMENTAL BIOLOGY]]</center></big> | <big><center>[[Developmental Biology - Anatomy & Physiology|'''BACK TO DEVELOPMENTAL BIOLOGY]]</center></big> | ||
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+ | ==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: | ||
+ | :Pronephros | ||
+ | :Mesonephros | ||
+ | :Metanephros | ||
+ | |||
+ | Mammals develop all three, and continue to use the metanephros in adult life. More primitive animals have only the first one or two. | ||
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+ | ==Pronephros== | ||
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+ | *''The earliest kidney. Develops in the anterior of the animal (adjacent to somites 7 - 10). Eliminated in later development''. | ||
+ | #At intervals along the intermediate mesoderm, dorsal evaginations occur. | ||
+ | #Evaginations extend caudally and eventually fuse with more caudal evaginations. | ||
+ | #*The caudal - most evagination fuses with the cloaca. | ||
+ | #Forms a continuous excretory tube to the cloaca. | ||
+ | #Capillaries develop at the medial aspect of the intermediate mesoderm so that waste can diffuse from the blood to the excretory channel. | ||
+ | #Connections between the intermediate mesoderm and somites as well between the intermediate mesoderm and lateral plate mesoderm break down. |
Revision as of 14:17, 31 August 2008
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:
- Pronephros
- Mesonephros
- Metanephros
Mammals develop all three, and continue to use the metanephros in adult life. More primitive animals have only the first one or two.
Pronephros
- The earliest kidney. Develops in the anterior of the animal (adjacent to somites 7 - 10). Eliminated in later development.
- At intervals along the intermediate mesoderm, dorsal evaginations occur.
- Evaginations extend caudally and eventually fuse with more caudal evaginations.
- The caudal - most evagination fuses with the cloaca.
- Forms a continuous excretory tube to the cloaca.
- Capillaries develop at the medial aspect of the intermediate mesoderm so that waste can diffuse from the blood to the excretory channel.
- Connections between the intermediate mesoderm and somites as well between the intermediate mesoderm and lateral plate mesoderm break down.