Chapter 31 The Nervous System Lecture Notes

The Nervous System


Function: The nervous system collects information about the body’s internal and external environment, processes that information and responds to it.

There are two parts to the Nervous system; The Central Nervous System & Peripheral nervous system. (CNS & PNS)

CNS= The brain and Spinal Cord

PNS= Nerves and supporting cells.

Information flow in
 the Nervous system


PNS: Gathers information & sends it to the CNS

CNS: Processes the information and forms a response

PNS: Carries the response of the CNS system to the glands and muscles.



The Nervous system impulses are transmitted by cells called neurons. (See Fig. 31-2)

Copy Fig. 31-2 into notes.


The Brain


Cerebrum: Largest portion of the brain controls voluntary conscious body activities. Site of intelligence, learning & judgment.

The Cerebrum has 2 sides called “hemispheres” (left and right).

 Thalamus: receives messages from sensory receptors and relays them to proper region of the cerebrum.

Hypothalamus: control center for recognition, analysis, hunger, thirst, fatigue, , anger & body temperature.

 Cerebellum: 2nd largest part of the brain, receives information about muscle & joint position and sensory input.

Brain Stem: connects the brain to the spinal cord. Regulates the flow of info from the spine/body to the brain.


Complete Nervous System Worksheet

Draw the brain onto your brown paper bag, label and color it. Use Page 903 as a guide DRAW THE PICTURE OF THE BRAIN THAT IS ON THE TOP OF PAGE 903 WITH THE LOBES. LABEL THE FOUR LOBES ON YOUR BAG ( Parietal, Occipal, Frontal & Temporal).