Nervous system definitions

The body system that controls and coordinates actions by sending electrical signals between the brain, spinal cord, and nerves.

Nervous System

The part of the nervous system made up of the brain and spinal cord, which processes information and makes decisions.

Central Nervous System (CNS)

All the nerves outside the brain and spinal cord that carry messages to and from the central nervous system.

Peripheral Nervous System (PNS)

A specialized nerve cell that transmits electrical and chemical signals throughout the body.

Neuron

A branched part of a neuron that receives messages from other nerve cells.

Dendrite

A long extension of a neuron that carries impulses away from the cell body.

Axon

A fatty covering around some axons that helps nerve signals travel faster and more efficiently.

Myelin Sheath

The small gap between neurons where chemical signals are passed from one neuron to another.

Synapse

A chemical messenger released at a synapse that transmits a signal to another nerve cell, muscle, or gland.

Neurotransmitter

The control center of the nervous system that regulates thoughts, memory, emotions, and voluntary movements.

Brain

A long bundle of nerve tissue that carries messages between the brain and the rest of the body.

Spinal Cord

A fast, automatic response to a stimulus that does not require conscious thought.

Reflex

The part of the nervous system that controls involuntary actions such as heart rate, digestion, and breathing.

Autonomic Nervous System (ANS)

A division of the autonomic nervous system that prepares the body for stress or emergencies (“fight or flight”).

Sympathetic Nervous System

A division of the autonomic nervous system that returns the body to a resting state and conserves energy ("rest and digest").

Parasympathetic Nervous System