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1. Cerebral Centre
2. Micturation Centre
3. Spinal Cord
4. Bladder 5. Urethra
6. Sphincter Muscles
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The nervous system is like your body’s internet. It is where feelings, memories and information are continuously circulated throughout the body to make you act in different ways.
The nervous system is made up of three parts: the brain, the spinal cord and the nerves.
The Brain
This is the central computer, it receives information from the nerves and from there it will either save the information or instruct the body to do something.
The Spinal Cord
This is a cable, about 1cm in diameter that runs from the brain through a ‘canal’ which runs down through the holes in the middle of the vertebrae (back bones). From the spinal cord, nerves spread out to all parts of the body. Except for the nerves that go to the eyes, the ears and other parts of the head – these go directly from the brain instead.
The Nerves
There are two kinds of nerves, one kind carries information to the spinal cord and the other carries information from the brain and the spinal cord.
For example: imagine you’re at the beach, a message from your toes to your brain would say ‘the water is cold’. This message is sent my a nerve to the spinal cord, which then sends it to the brain. The brain gives an order ‘get your feet out of the water!’. This order from the brain goes through the spinal cord and along a nerve to the leg muscle that can pull your toes out of the water.
Sometimes you need to act fast, if you touch a very hot pan in the oven, the message only goes to the spinal cord which then immediately gives your arm muscle and instruction to pull your hand away from the pan. This is called a ‘reflex action’. If the message had been forced to go all the way to the brain, get processed and sent back to the arm, you may have burned yourself.
Other reflex actions include blinking, sneezing and putting your hands out when you fall.
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