The Structure of the Nervous System

Module 7: Neural and Hormonal Systems

The Nervous System

Central Nervous System (CNS)

• The brain and spinal cord• The brain is the location of most

information processing.• The spinal cord is the main pathway to

and from the brain.

Divisions of the Nervous System

Peripheral Nervous System (PNS)

• The sensory and motor nerves that connect the central nervous system to the rest of the body

• Peripheral means “outer region”• The system is subdivided into the

somatic and autonomic nervous systems.

Divisions of the Nervous System

Somatic Nervous System• The division of the peripheral nervous

system that controls the body’s skeletal muscles

• Contains the motor nerves needed for the voluntary muscles

• Ex. – your CNS develops idea to walk – your motor and sensory nerves in SOMATIC NS carry out the command

Divisions of the Nervous System

Autonomic Nervous System(think autopilot)

• The division of the peripheral nervous system that controls the glands and muscles of the internal organs

• Monitors the autonomic functions• Controls breathing, blood pressure, and

digestive processes (you don’t control these – they happen on their own)

• Divided into the sympathetic and parasympathetic nervous systems

Divisions of the Nervous System

Sympathetic Nervous System

• The part of the autonomic nervous system that arouses the body to deal with perceived threats

• Fight or flight response

Divisions of the Nervous System

Parasympathetic Nervous System

• The part of the autonomic nervous system that calms the body

• Brings the body back down to a relaxed state

Divisions of the Nervous System

The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

Application Activity • Scenario: The first snow storm of the

season is unexpectedly here. You have been dismissed early from school and you have to drive your parents’ car home. On your way home on the unplowed and untreated streets, a car is suddenly in your lane headed straight for you. An accident seems inevitable. Step – by –step, describe what happens in your nervous systems before, during and after the crash.