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*Somites differentiate to produce:
 
*Somites differentiate to produce:
 
:'''Scelerotome''' - develops into axial skeleton, ribs and vertebrae.
 
:'''Scelerotome''' - develops into axial skeleton, ribs and vertebrae.
:'''Dermomyotome''' - develops into myotome and dermotome.
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:'''Dermomyotome''' - develops into ''myotome'' and ''dermotome''.
 
::'''Myotome''' - develops into skeletal muscle of the limbs and body.
 
::'''Myotome''' - develops into skeletal muscle of the limbs and body.
 
::'''Dermotome''' - develops into the dermis.
 
::'''Dermotome''' - develops into the dermis.
 
*Somites develop in an identical manner, although those at the posterior develop after those at the anterior.
 
*Somites develop in an identical manner, although those at the posterior develop after those at the anterior.
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*The chick has 12 somites.
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''Stages of somite maturation as observed along the anterior - posterior axis:''
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===Somites I - III===
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*These are the most newly formed somites, and are therefore at the posterior of the embryo.
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*Somites are simple at this stage, with epithelial cells surrounding an inner cavity that is filled with mesenchymal pre - somitic mesoderm cells. These cells are called '''somitocoel cells'''.
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*All cells are undergoing mitosis.
    
==Species Differences==
 
==Species Differences==
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