the nervous system nervous system – the entire network of neurons in the body. includes: central...

Divisions of the Nervous System

The Nervous SystemNervous System –

The entire network of neurons in the body.Includes:

Central Nervous System

Peripheral Nervous System

Their subdivisions

The Central Nervous SystemCentral Nervous

System – The brain and spinal cord.“Command Central”

The Central Nervous SystemThe Brain

Makes complex decisions

Coordinates body functions

Initiates our behaviors

Responsible for voluntary movements

The Central Nervous SystemThe Spinal Cord

Serves as a sort of neural cable, connecting the brain with parts of the peripheral nervous system extending into the trunk and limbs.

Does not connect the brain to internal organs.

Responsible for simple reflexes.

The Peripheral Nervous SystemThe Peripheral

Nervous System – Plays a supportive role, connecting the central nervous system with the rest of the body through bundles of sensory and motor axons, called nerves.

The Peripheral Nervous SystemCarries messages

between the brain and:Sense Organs (eyes,

ears, etc.)Internal OrgansMuscles

The Peripheral Nervous SystemThe “Pick-up and

Delivery Service” for the Central Nervous System.

Divisions of the PNSSomatic Nervous

SystemCarries sensory

information to the central nervous system.

Sends voluntary messages to the body’s skeletal muscles.

Divisions of the PNSAutonomic Nervous

System Sends

communication between the central nervous system and the internal organs and glands. Regulate digestion Respiration Heart Rate Arousal

Divisions of the PNSSympathetic Division

Part of the Autonomic nervous system

Sends messages to internal organs and glands that help us respond to stressful and emergency situations.

Divisions of the PNSParasympathetic

DivisionPart of the

autonomic nervous system

Monitors the routine operations of the internal organs.

Returns the body to calmer functioning after arousal by the sympathetic division.

The Nervous System and DrugsAgonist – Drug or other chemical that

enhances or mimics the effects of neurotransmitters.

Antagonist – Drug or other chemical that inhibits the effects of neurotransmitters.