Front

Central nervous system (CNS)

Back

The entire complex of neurons, axons, and supporting tissue that constitute the brain and spinal cord.

Front

Peripheral nervous system (PNS)

Back

The nerves, made up of sensory and motor neurons, that connect the central nervous system (CNS) to the rest of the body.

Front

Autonomic nervous system (ANS)

Back

The part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart).

Front

Sympathetic nervous system (SNS)

Back

The division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations.

Front

Parasympathetic nervous system (PSNS)

Back

The division of the autonomic nervous system that calms the body, conserving its energy.

Front

Somatic nervous system

Back

The division of the peripheral nervous system that controls the body’s skeletal muscles.

Front

Nervous system

Back

The body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.