Table of Contents

Nervous System and Brain

What is the Nervous System?

The nervous system has three main parts: the brain, the spinal cord and the nerves. Information races back and forth from one end of your body to the other. Some of these messages are controlled by you but others work automatically without you worrying about them. Lucky for you! Can you imagine having to remind your heart to beat or your lungs to breathe? You wouldn't have time to have fun!

What is the Brain?

If you must know, it's really just a 1.3 kilogram blob of pinkish-gray tissue. But, oh, what a magnificent blob it is! It is composed of 10 BILLION cells! All 10 billion cells are linked together to allow lightning-fast transmission of information.

The brain controls all vital body functions such as sleep, hunger and thirst. It also controls emotions, so if you're in love blame it on your brain not your heart!

The brain (your brain!) has three main parts: the cerebrum, the cerebellum and the brain stem.

The Cerebrum:

This is the "big kid" of brain parts. It makes up about 85% of the weight of the entire brain. Its surface is called the cortex. Two main parts, the left and right hemispheres divide the cerebrum in two. These hemispheres are connected by a bundle of nerves called the corpus callosum (no kidding!).

This is the most highly developed part of the brain. Such activities like sense of touch, taste, sight, hearing and smell, voluntary muscle movement, language, thinking and memory are carried on here.

The Cerebellum:

The cerebellum is found underneath and behind the hemispheres. It is in charge of movement, reflexes, posture, balance and so on. Whether you want to throw a ball or impress everyone with your dancing ability the cerebellum is the brain part for you.

The Brain Stem:

The brain stem is the lower part of the brain and controls basic functions such as: sleeping, eating, and emotional responses.