What is white matter dominated by?

What is white matter dominated by?

myelinated neurons dominate are called white matter. Efferent, or motor, nerve fibres carry impulses away from the central nervous system; afferent, or sensory, fibres carry impulses toward the central nervous system.

What axons are in white matter?

White matter is found in the deeper tissues of the brain (subcortical). It contains nerve fibers (axons), which are extensions of nerve cells (neurons). Many of these nerve fibers are surrounded by a type of sheath or covering called myelin. Myelin gives the white matter its color.

Are axon terminals found in white matter?

Gray matter, named for its pinkish-gray color, is home to neural cell bodies, axon terminals, and dendrites, as well as all nerve synapses. This region passes sensory information via ascending nerve signals to the brain.

What are the components of white matter?

White matter is one of the two components of the central nervous system and consists mostly of glial cells and myelinated axons. The white matter is white because of the fatty substance ( myelin ) that surrounds the nerve fibers. Myelin acts as an electrical insulation.

What is myelinated axon?

The myelinated axon can be likened to an electrical wire (the axon) with insulating material (myelin) around it. Myelin is formed in the central nervous system (CNS; brain, spinal cord and optic nerve) by glial cells called oligodendrocytes and in the peripheral nervous system (PNS) by glial cells called Schwann cells.

Is the corpus callosum white matter?

The corpus callosum is the largest white matter structure in the brain, consisting of 200-250 million contralateral axonal projections and the major commissural pathway connecting the hemispheres of the human brain.

Is white matter made up of glial cells?

You’ve likely heard of the gray matter of the brain, which is made up of cells called neurons, but a lesser-known type of brain cell is what makes up the white matter. These are called glial cells.

What are axons composed of?

There are two types of axons in the nervous system: myelinated and unmyelinated axons. Myelin is a layer of a fatty insulating substance, which is formed by two types of glial cells: Schwann cells and oligodendrocytes. In the peripheral nervous system Schwann cells form the myelin sheath of a myelinated axon.