Nervous tissue

Nervous tissue, also called neural tissue, is the main tissue part of the nervous system. The nervous system helps control and manage all the body's functions and actions. It has two main parts: the central nervous system, which includes the brain and spinal cord, and the peripheral nervous system, made up of many branching nerves.

Nervous tissue is made of special cells called neurons, or nerve cells, and supporting cells called neuroglia. Neurons can receive and send electrical signals, called nerve impulse, throughout the body. These signals help coordinate everything we do.

Inside each neuron is a long part called an axon. Axons send signals to other cells. Many axons together form the nerves in the peripheral nervous system and tracts in the central nervous system. The nervous system also helps us feel things, make decisions, control our muscles and glands, keep our body balanced, and think and feel emotions.

Structure

See also: Brain cell

Nervous tissue is made up of special cells called neurons and other supporting cells called neuroglial cells. Neurons can send electrical signals, called action potentials, to each other. They have a main body, called the soma, with branches called dendrites that receive signals and a long branch called an axon that sends signals to other neurons.

Neuroglial cells come in many types and help support neurons in different ways. Some help protect neurons, while others help send signals faster by wrapping the axons in a special covering called myelin.

Function

Nervous tissue helps the nervous system send messages throughout the body by carrying electric signals. In the central nervous system, which includes the brain and spinal cord, there are areas called grey matter that help process information, and white matter that connects these areas. In the peripheral nervous system, special groups of cells called ganglia act as relay points, and bundles of nerve fibers carry the signals.

Clinical significance

Nervous tissue can develop growths called tumours. Some of these tumours include gliomas, which come from glial cells, and neuroepitheliomatous tumours such as neuroblastoma. There are also tumours that grow from nerve sheath cells, like neurofibroma and schwannoma. These tumours can affect how the nervous system works.