Changes

*At the dorsal aspect of the somite, some cells of the dermomyotome are ingressing to form a new layer between the dermomytome and sclerotome; the '''myotome'''.

*At the dorsal aspect of the somite, some cells of the dermomyotome are ingressing to form a new layer between the dermomytome and sclerotome; the '''myotome'''.

*Ingression occurs at two points; ventral - laterally and dorsal - medially.

*Ingression occurs at two points; ventral - laterally and dorsal - medially.

:'''Ventral - lateral ingression develops into ''hypaxial muscle''. This forms muscle of the body and limb.'''

:'''Ventral - lateral ingression develops into ''hypaxial [[Muscles - Anatomy & Physiology|muscle]]''. This forms [[Muscles - Anatomy & Physiology|muscle]] of the body and limb.'''

:'''Dorsal - medial ingression develops intp the ''epaxial muscle''. This forms the muscles of the dorsum.'''

:'''Dorsal - medial ingression develops intp the ''epaxial [[Muscles - Anatomy & Physiology|muscle]]''. This forms the [[Muscles - Anatomy & Physiology|muscles]] of the dorsum.'''

*Myotomal cells do not have the ability to undergo mitosis. To increase cell numbers, cells are recruited from the dermomyotome.

*Myotomal cells do not have the ability to undergo mitosis. To increase cell numbers, cells are recruited from the dermomyotome.

*After all the myotomal cells have ingressed what remains of the dermomyotome becomes the dermotome.  

*After all the myotomal cells have ingressed what remains of the dermomyotome becomes the dermotome.  

*''The dermotome, which lies dorsally in the somite, forms the dermis.''

*''The dermotome, which lies dorsally in the somite, forms the [[Skin - Anatomy & Physiology#Dermis|dermis]].''

 

===Somites XI Onward===

===Somites XI Onward===