Nerves

What is a nerve? It is a cable like structure within the body. It consists of a number of fibres within it that form a system. Hence this system is called as Nervous system. This nervous system is involved in control and the coordination of all the parts of the body. Usually the Nerves are made up of nerve fibres called as Axons. These are the basic elements that constitute a nerve.

Nerves  The nervous system not only sends and receives messages but also processes them into chemical signals called as impulses in the human body. A wide network of nerves is spread throughout our body which also runs through the brain, the spinal cord and many organs.

Structure of a Nerve

The basic structure of a nerve is as shown below Structure of a Nerve A nerve consists of a cordlike structure with a multiple of nerve fibres called as axon. This axon has a layer called as connective tissue around it. This connective tissue is called as endoneurium. And this entire nerve is enclosed in this layer of connective tissue called as the epineurium. Hence these Nerves are responsible for all the activities done by human beings in day to day life.

Types of Nerves and their Function in Human Body-
There are three types of Nerves in the human body naming Sensory nerves, motor nerves and mixed nerves.

  • Sensory nerves- These are the nerves that send messages to the brain or the spinal cord from the sense organs. These are enclosed in the form of a bundle like structures or nerve fibres in the peripheral nervous system. They caary information from the PNS to the CNS( Central nervous System).• Motor Nerves- Motor nerves are those nerves those that carry the messages in the form of a response from the brain or the spinal cord to other parts of the body such as the muscles and glands. They are responsible in carrying the information from the CNS to the PNS.•  Mixed Nerves- These are the nerves that perform both the action of sensory nerves as well as motor nerve. The transform electrical impulses from the central nervous system to the muscles of the body. Generally the nerves transmit impulses at the rate of 120 meter per second.

Human BodyThe above  picture describes about how the sensory and the motor nerves function in the human body.


Practise This Question

Given below are few statements about sexual reproduction.
Choose the correct set of statement(s).

1. Involves fusion of male and female gametes.

2. Females usually produce more gametes when compared to males.

3. It is an elaborate, complex and slow process.

4. Offsprings are genetically identical among themselves but different from parents.