The main difference between gray and white matter is in their composition. White matter is made up of long neural fibers called axons, which are covered in myelin, while gray matter is made up of neural cell bodies, axon terminals, synapses and short neural fibers, or dendrites.Continue Reading
Gray and white matter are located in the central nervous system, that is, in the brain and in the spine. In humans, gray matter forms a butterfly shape in the spine and is surrounded by white matter, while in the brain, white matter is on the inside and gray matter is on the outside.
Apart from composition and location, gray and white matter differ in function. Axons, which make up white matter, have the role of sending information from the cell body to other neurons, muscles or glands. Axons are covered with a myelin sheath, whose role is to insulate the fiber and enable speedier electrical communication between neurons. If the myelin sheath is damaged, diseases, such as multiple sclerosis, can occur.
The synapses in gray matter are junctures that enable the transfer of information from one neuron to another via axon terminals. The dendrites have the role of receiving information from other cells. Unlike the axon, which sends impulses away from the cell body, dendrites carry impulses from synapses to the body of the cell.Learn more about Human Anatomy