Differentiation and Development 1
Specialisation of the Mesoderm
- Forms all body parts except:
- Nervous
- Skin
- Epidermal derivatives
- Epithelial and glandula derivates of mucosa
- 1st evidence of mesodermal differentiation is appearance of notochord
- Aggregates form either side of notochord e.g. somites
- Around those are the intermediate mesoderm and lateral mesoderm
- Each somite has 3 functional parts:
- Sclerotome - forms vertebrae and ribs
- Dermatome - forms dermis of skin in dorsal part of body
- Myotome - forms skeletal muscles of neck, body trunk, limbs
- Intermediate mesoderm - forms gonads, kidneys and adrenal cortex
- Lateral mesoderm:
- Somatic - forms dermis of skin in ventral body region and limb buds
- Splanchic - forms cardiovascular system, organs and most connective tissue