Question

nervous system explanation

Answer 1

In the multicellular organisms the various activities of the body are control and regulated by a specific system called as nervous system.
In other words we can say that in animals along with understanding thinking and remembering any substance a system maintaining a coordination and regulations in the functioning of various organs is present - "the nervous system".
In man and animals, the nervous system is formed by specific types of cells, these cells are called as neuron. Each neuron cell consists of nerve cells and nerve fibres.
Nervous system of man and other vertebrate animals is divided into two parts-
1. central nervous system
2. peripheral nervous system

The main part of the nervous system which controls the whole body organ system and autonomic nervous system is called central nervous system. This includes brain and spinal cord.
Functions of nervous system are-
1. Regulate and control all the activities of the body.
2. The sensory organs of the system receives all the activities occuring in the external environment.
3. Protect the body by reflex action.
4. Maintain coordination in all the tissues and organs of the body.
5. Controls the internal environment.

hope this helped you!!!

Answer 2

Answer:

The nervous System:

One of the most perplexing and vital systems which takes place in all the organisms (proving its significance); The nervous system has  been broadly classified in to two categories. Central Nervous System and Peripheral Nervous System.

The nervous system enables our body to:

- React and respond to internal and external changes occurring.

- Send messages to different parts of the body through Nerve Impulses.

Now, the two categories (peripheral and central nervous system) are described as the following:

Central Nervous System:

It compiles of all the actions taken place by our Brain and Spinal Cord.

Peripheral Nervous System:

It compiles of all the actions taken place by our Nerves.

To further more describe the Nervous System, we also need to know that all the actions we are performing are voluntary actions. Picking up a book, walking, talking e.t.c. All the actions that you willingly do. Yet, many activities are performed by our Autonomic Nervous System.

Autonomic nervous system performs all our involuntary tasks, such as; Heart beat, blood pressure, respiration, digestion, gas exchange, e.t.c.

But, involuntary actions also compile of a Reflex Action.

This Reflex Action is an involuntary action, yet very involuntary action isn't a reflex action. The reason for that is, because in order for a reflex action to take place, we need to have a stimulus (something that urges us to do it).

For e.g:

If you are walking and you step on a nail, you will immediately jerk back.  

Nail is the Stimulus (Stimuli for plural)

Jerk Back is the Reflex Action.

We have already got into a detailed explanation, and so to conclude, let me tell you the basic parts of a brain:

Cerebrum: The largest part which initiates and coordinates movement and regulates temperature. Other areas of the cerebrum enable speech, judgement, thinking and reasoning, problem-solving, emotions and learning. Other functions relate to vision, hearing, touch and other sensory organs.

Cerebellum: Muscle co-ordination and balance.

Medulla Oblongata: Control Autonomic activities.

Brain stem: Autonomic nervous system (with medulla oblongata) and a bridge from the brain to the Spinal Cord.