The Nervous System
The Nervous system controls all the function of our body such as working, breathing, playing, remembering names and lessons, statical data, eating and digesting food & driving and talking.
Nervous system main parts
The Nervous system consists of the the brain spinal cord and a network of nerves.
The brain is the control centre of our body. It is protected by the hard skull. The brain has three main parts– Cerebrum, Cerebellum and Medulla oblongata.
The cerebrum is the thinking part of our brain. It control our voluntary muscles. It help us learn, hear, think and remember. We use the the cerebrum while solving math problems or statistical data or running in the field/playground. Cerebrum also control our feelings sach as happiness, sadness and fear.
The cerebellum is located in the back of your brain. The cerebellum is a part of the brain that play a vital role in virtually all physical movement. The cerebellum is responsible for our posture, body balance or equilibrium, sense of body position, movement and coordination of muscles & moter skills/learning. Thus, za cerebellum help us stand straight without losing our balance.
Your middle of yoghurt is located at the base of your brain.
The Medulla or the brainstem connects the brain to the spinal cord. It plays an essential role in passing message between your spinal cord and brain. It’s also essential for regulating your cardiovascular and respiratory system. It controls our involuntary muscles responsible for actions such as respiration/breathing, heart beats, blood circulation, swallowing and digestion, coughing and sneezing.
The spinal cord and the nerves
Our body has a vast network of nerves. The nerves carry message back and forth between the brain and the rest of body via the spinal cord. The spinal cord is a long and thick bundle of nerves protect by the vertebrae. The spinal cord is connected to the brain at the medulla. There are three types of nerves in our body: Sensory nerves, Motor nerves, Mixed narves.
Sensory nerves carry message from the eyes, nose, ear, tongue and the skin (sense organs) to the brain or the spinal cord.
Motor nerves carry order from the brain or the spinal cord to the rest of the body.
Mixed nerves carry both message and order to and from the brain or the spinal cord. Normally, sensory nerves carry message to the spinal cord. The spinal cord then send the message to the brain. After the brain receive a message it send a response through the spinal cord to motor nerves to carry out the action.
Reflex action are directly controlled by the spinal cord. A reflex action is an automatic (involuntary) and rapid response to a stimulus, which minimises any damage to the body from potentially harmful conditions, such as touching something hot or cold. Sometimes our body need to act quickly for its safety. For an example, when we accidentally touch a sharp object, we pull back our hand immediately to avoid getting hurt. In such cases, there is not enough time for a message to reach the brain. So as soon as the spinal cord receive the message, it sends the order directly to the hand. Instantly, we pull back our hand even therefore realising what happened. This is called reflex action. Reflex action are directly controlled by the spinal cord. A reflex action follows this general sequence and does not involve the conscious part of the brain such as stimulus to receptor, receptor to sensory neurones, sensory neurones to relay neurone, relay neurone to motor neurone, motor neurone to effector, effector to response.
The nerve pathway followed by a reflex action is called a reflex arc. For example, a simple reflex arc happens if we accidentally touch something hot or cold.
I hope you liked this article.
(GS India Nursing Academy, Lucknow, UP, India)