An adult brain weighs about 3 pounds and uses only 10 or 12 watts of electricity Yet that small organ in your head can do many more jobs than the biggest and fastest computer ever made Your brain directs and controls all the muscles and organs in your body It receives messages from your eyes ears nose tongue and skin and makes sense of the world around you It stores information in your memory It is involved in everything you do from eating and growing to running and sleeping to breathing and thinking Although your brain makes up only 2 percent of your body’s weight it needs 20 percent of your body’s oxygen It needs oxygen day and night because even when you sleep your brain is busy at work sometimes dreaming but always keeping your heart beating your lungs breathing your muscles moving If the supply of oxygen to your brain stops for just 10 seconds you will lose consciousness IT LOOKS LIKE A PINKISH-GRAY CAULIFLOWER
HERE it is the human brain i’ve separated the halves so you can see inside
A human brain is made up of 50 100 billion tiny nerve cells called neurons That’s about the same amount as the number of stars in the Milky Way Galaxy There are 10 times that number of glial cells in the brain which surround support and nourish the neurons Each neuron can carry electrical and chemical signals An electrical signal flashes down a neuron When it reaches the end of the neuron the signal triggers the release of certain chemicals The chemicals reach other nearby neurons and trigger them into sending signals In this way signals can travel back and forth across the brain in a tiny fraction of a second No neuron works just by itself Each neuron connects with many other neurons in your brain and all over your body The place where a nerve impulse travels from one neuron to another is called a synapse Groups of neurons in your brain seem to have certain jobs I ALWAYS TURN TO THE LAST page first to see how it comes out
Thousands take part in even the simplest actions such as moving your fingers or turning your head Millions of signals flash through your brain every moment of your life They bring information about your insides your heartbeat your breathing your temperature and other body processes outside your awareness They bring news about an itch in your nose the sound of a song on a radio the smell of an apple Inside your brain millions of other signals work on the incoming information and produce memories thoughts emotions and plans on what to do next Signals are sent out from your brain to scratch your itchy nose change the radio station bite the apple Meanwhile your brain is also sending out commands to keep your body functioning at its best Each task uses several different regions of your brain
