The nervous system is an incredible important part of the body. Everything you do will require your nervous system, from opening your eyes to typing on a computer.
Your nervous system is a complex web of nerve cells (neurons) all communicating with each other to send a message from one part of your body to another. The main control centre of your nervous system is your Brain. All information about the outside world is sent through nerve impulses to the brain, and then interpreted into information, allowing you to make a decision. This decision may be conscious or unconscious.
The nervous system is broken up into two parts the
Central Nervous System (CNS)
Composed of the brain and spinal cord
Peripheral nervous system (PNS).
Composed of all the other parts of the nervous system.
As you can see by the animation to the left, the PNS carries information to and from the CNS.
The CNS is responsible for processing and co-ordinating information received. Controlling both voluntary (actions which we think about) and involuntary (heart beat or breathing) actions.
Different regions of the brain are responsible for specific functions. Scroll over each area of the brain bellow
So we can divide the nervous system into two parts structurally (CNS & PNS), and we can divided into two parts functionally (Somatic and Autonomic).
As we said above there are some parts of the nervous system which are involuntary (i.e. heart rate, breathing, pupil dilation etc) and others which require conscious thought such driving a car.
Voluntary actions fall under the Somatic nervous system. Everything from chewing your food to making a fist uses the somatic nervous system. All involuntary actions are controlled by the Autonomic nervous system.
Autonomic nervous system
We can break this system up into the:
Sympatheticnervous system
Increasing energy use
Prepares the body for action
Increases heart and metabolic rate. (Fight or Flight response)
Parasympathetic nervous system
Promotes conservation of energy
Decreases heart rate.
Observe the video bellow.
As you can see in the video. The women’s sympathetic nervous system is activated. Her heart rate, metabolic rate and breathing rate all increase dramatically. Her body is preparing it self for the up coming danger.
Once the sling shot ride stops, her Parasympathetic nervous system kicks in, slowley decreasing her heart rate, trying to return the body back to normal.
Questions
1. This is made up of the brain and spinal cord.
A. Peripheral nervous system
B. Central nervous system
C. Enteric nervous system
2. This part of the brain controls coordination and balance.
A. cerebrum
B. cerebellum
C. medulla oblongata
3. This is the job of the nervous system.
A. To send messages to and from the brain and spinal cord to and from the body.
B. To break down food to be used by the body.
C. To remove wastes from the body.
4. Nerves in you hand are apart of which system?
A. PNS
B.CNS
C.ANS
D.DNS
5. (The following information is fictional). A north American deer often grazes on white pine leaves. As the area it lives in is now populated by people, roads have been built right through their feeding grounds. As such, they are a constant risk to many motorists. Explain the activation of the deer’s nervous system when it is being approached by an on coming car?
Use terms such as Automatic, Sympathetic and Parasympathetic in your explanation.
In terms of speed, the nervous system is extremely fast in absorbing sensory information, processing it and acting on it.
The video to the right show IP man fighting. Fighting requires you too process sensory stimuli, interpret it and act appropriately. No other system in the body can do this as fast an the nervous system.
