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Limb Development - Anatomy & Physiology (view source)
Revision as of 18:45, 29 August 2008
, 18:45, 29 August 2008→Limb Bud Formation
*Proliferation of the lateral plate mesoderm cannot sustain entire limb growth; instead the '''apical ectodermal ridge (AER)''' maintains growth.
*Proliferation of the lateral plate mesoderm cannot sustain entire limb growth; instead the '''apical ectodermal ridge (AER)''' maintains growth.
**The AER develops as mesenchymal cells cause cells of the overlying ectoderm to change their morphology from cuboidal to columnar.
**The AER develops as mesenchymal cells cause cells of the overlying ectoderm to change their morphology from cuboidal to columnar.
**This can be seen when looking at the limb bud in a distal to poximal direction.
**The ridge can be seen when looking at the limb bud in a distal to poximal direction.
*The AER maintains an area of rapidly proliferating cells beneath it, called the '''progress zone (PZ)'''.
*The rapidly increasing number of cells drives the limb bud out distally, elongating the limb.
*Cells leave the PZ, and as they do so they differentiate.
==Patterning of the Limb==
==Patterning of the Limb==