Bumpy Brains University

Nervous System (NS)

Let's break down the NS:

The NS is made up of 2 systems:

central NS
peripheral NS

The central NS is made up of the:

brain
spinal cord

The peripheral NS is made up of the:

somatic NS
autonomic NS

The autonomic NS is made up of the:

sympathetic NS
parasympathetic NS

Central Nervous System (CNS)

Vinny's CNS is pictured to the right of Vinny. The CNS is made up of the:

Brain:

Controls how you get around in your world
Made of 100,000,000,000 neurons and lots more glial cells
Hangs out in the skull
Weighs 3 pounds

Spinal cord:

Brings information to and from your brain
Hangs out in the spinal column (made of 33 bones)
Axons make up the nerves of the cord
Average size is 15-17 inches (depends on how tall you are)

Peripheral Nervous System (PNS)

Autonomic Nervous System

Somatic Nervous System

This system makes actions that are automatic, like with homeostasis (keeping a perfect balance of your body, such as drinking when thirsty) and heart rate. Sometimes though, we have control, such as breathing.

Autonomic NS

These nerves control your body because they are connected to your muscles.

Try it: Take a deep breath.

Try it: Make a muscle.

Sympathetic NS	Parasympathetic NS
Vinny's cat is scared by a spider. His sympathetic NS will work very hard so he can do something about being scared - like run or fight the spider.	Vinny and his cat are watching TV and relaxing. Now, their parasympathetic NSs are working.
Vinny's cat's heart is beating very fast, his pupils are dilated, blood pressure is increased. He will not need to use the litter box soon!	They are digesting their food, pupils are constricted, and after drinking that glass of juice, Vinny will pee.

	Copyright © 2009, Bumpy Brains - Last updated on February 28, 2009