nephrotome
Quick Summary
The nephrotome is a developmental structure in vertebrates that gives rise to the kidneys. These cellular plates connect somites to the mesodermal sheets lining the body cavity. In primitive vertebrates, each nephrotome forms a single tubule. However, in most vertebrates, adjacent nephrotomes fuse to form a larger mass that differentiates into multiple tubules, regardless of the original segmentation of the mesoderm.12
These tubules can develop into different types of kidneys at various stages of embryonic development:
* Pronephros: The most anterior and earliest functional kidney, found in fish and amphibian larvae.1
* Mesonephros: Develops later and functions as the kidney for adult fish and amphibians, as well as for embryos of reptiles, birds, and mammals.13
* Metanephros: The permanent kidney found only in reptiles, birds, and mammals, developing from the posterior part of the trunk.12
In some cases, the nephrotome tissue is influenced by outgrowths from the mesonephric duct, which form the ureter and collecting tubules of the metanephros.12
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animal developmentExcretory organs…the stalks of somites called nephrotomes. In some primitive vertebrates such as cyclostomes, the nephrotome in each segment gives rise to only one tubule, but, in the great majority of vertebrates, mesenchyme from adjacent nephrotomes fuses into a common mass that differentiates into a number of nephric tubules irrespective of…
Read More…the stalks of somites called nephrotomes. In some primitive vertebrates such as cyclostomes, the nephrotome in each segment gives rise to only one tubule, but, in the great majority of vertebrates, mesenchyme from adjacent nephrotomes fuses into a common mass that differentiates into a number of nephric tubules irrespective of…
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prenatal developmentUrinary system…from the cellular plates called nephrotomes that connect somites with the mesodermal sheets that bound the body cavity. The vestigial pronephros is represented solely by several pairs of tubules; they join separately formed excretory ducts that grow downward and enter the cloaca, the common outlet for urine, genital products, and…
Read More…from the cellular plates called nephrotomes that connect somites with the mesodermal sheets that bound the body cavity. The vestigial pronephros is represented solely by several pairs of tubules; they join separately formed excretory ducts that grow downward and enter the cloaca, the common outlet for urine, genital products, and…
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