The brain

The brain lies within the skull and is shaped like a mushroom.  The brain consists of four principal parts:

• the brain stem
• the cerebrum
• the cerebellum
• the diencephalon

The brain weighs approximately 1.3 to 1.4 kg. It has nerve cells called the neurons and supporting cells called the glia.

There are two types of matter in the brain:  grey matter and white matter.  Grey matt...