The Central Nervous System
Gray matter is a major part of the central nervous system, which consists of neuronal cell bodies, neuropil (dendrites and myelinated as well as unmyelinated axons), glial cells (astroglia and oligodendrocytes), synapses and capillaries.
Gray matter contains numerous cell bodies and relatively few myelinated axons, while white matter contains relatively very few cell bodies and is composed chiefly of long-range myelinated axon tracts. The color difference arises mainly from the whiteness of myelin. In living tissue, gray matter actually has a very light gray color with yellowish or pinkish hues, which come from capillary blood vessels and neuronal cell bodies.
Gray matter also denotes one’s brain or intellect.
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