Editing Mesoderm (section)

==Definition==
The mesoderm is one of the three germinal layers that appears in the third week of [[embryonic development]]. It is formed through a process called [[gastrulation]]. There are four important components, which are the [[axial mesoderm|axial]], ⁣[[paraxial mesoderm|paraxial]], [[intermediate mesoderm|intermediate]], and [[lateral plate mesoderm]]s. The axial mesoderm gives rise to the [[notochord]]. The paraxial mesoderm forms the [[somitomere]]s, which give rise to [[mesenchyme]] of the head, and organize into [[somite]]s in occipital and caudal segments, and give rise to [[sclerotome]]s (cartilage and bone), and dermatomes (subcutaneous tissue of the skin).<ref name="RFB2004Mesoderm" /><ref name="Langman's Medical Embryology 2010" /> Signals for somite differentiation are derived from surroundings structures, including the notochord, [[neural tube]], and [[epidermis]]. The intermediate mesoderm connects the paraxial mesoderm with the lateral plate. Eventually it differentiates into urogenital structures that consist of the kidneys, gonads, their associated ducts, and the adrenal cortex. The lateral plate mesoderm gives rise to the heart, blood vessels, and blood cells of the circulatory system, as well as to the mesodermal components of the limbs.<ref name="Scott-2010">{{Cite book |last=Scott, Gilbert |title=Developmental biology |publisher=Sinauer Associates |year=2010 |edition=ninth |location=US}}</ref>

Some of the mesoderm derivatives include the muscle (smooth, cardiac, and skeletal), the muscles of the tongue (occipital somites), the pharyngeal arches muscle (muscles of mastication, muscles of facial expressions), connective tissue, the dermis and subcutaneous layer of the [[skin]], [[bone]] and cartilage, dura mater, the [[endothelium]] of [[blood vessels]], [[red blood cells]], [[white blood cells]], [[microglia]], the [[dentin]] of teeth, the kidneys, and the adrenal cortex.<ref name="Dudek-2009">{{Cite book |last=Dudek, Ronald W. |title=High-yield. Embryology |publisher=Lippincott Williams & Wilkins |year=2009 |edition=4th}}</ref>