Explain the nerve cell structure and function, Biology

Assignment Help:

Explain the Nerve Cell Structure and Function?

Before studying the organization of the nervous system, we will look at the relationship between structure and function of nerve and associated cells. The typical nerve cell or neuron has a cell body containing the nucleus, and an elongated extension called an axon that carries electrical signals called impulses away from the cell body. The axon is frayed at the end to form many synaptic terminals that transmit the nerve impulse to a target cell in a contact space called a synapse. The nerve impulse is carried across the synapse by certain chemicals called neurotransmitters. These chemicals are enclosed in synaptic vesicles that fuse with the presynaptic membrane and are released in response to a nerve impulse that reaches the axon terminal. Neurotransmitters bind to the postsynaptic membrane of the target cell, which can be a muscle, a gland, or the terminals of another neuron that takes over to propagate the nerve impulse. After the impulse is propagated, enzymes in the synaptic space break down the remaining neurotransmitter chemicals.

Surrounding the nerve cell body are short, branched extensions called dendrites, that bind neurotransmitters released by other neurons or by sensory receptors, cells associated with the five senses - touch, vision, hearing, taste, and smell. Some sensory receptors are actually specialized neurons.

Axons of some nerve cells are surrounded by a protective sheath of membranous material called myelin, produced by accessory cells called Schwann cells. Myelin gives bundled nerves their white appearance. Myelin is not continuous along the axon, but the sheath is interrupted at regular intervals called nodes of Ranvier, where the nerve is unmyelinated.

 

 


Related Discussions:- Explain the nerve cell structure and function

Explain viruses and their classification, Explain Viruses and their classif...

Explain Viruses and their classification? Viruses are living organisms. Viruses are not living organisms. No, the above is not a misprint! In fact, viruses defy the normal c

Methods of filter feeding, Methods of Filter Feeding More elaborate me...

Methods of Filter Feeding More elaborate methods of filter feeding are seen in tube dwelling polychaetes which use tentacles to entangle the food particles. Figure shows some

What are the major cells of which poriferans are made, Q What are the major...

Q What are the major cells of which poriferans are made? Sponges have their external wall covered by flat cells called pinacocytes and having pores well-delimited by special ce

Define the mechanism of evolution, A few statements about the mechanism of ...

A few statements about the mechanism of evolution are made. Mark the correct statements.   (i)  Evolution happens at the individual level as well as population level. (ii

Explain glucokinase, Glucokinase In the fed state, clearance of blood  ...

Glucokinase In the fed state, clearance of blood  glucose is mainly by  liver via glucokinase. Glucokinase, which  is an  inducible enzyme, removes most of the blood glucose fr

Morphogenesis of an ectodermal derivative, Morphogenesis of an Ectodermal D...

Morphogenesis of an Ectodermal Derivative During the development of vertebrate body the dissimilar regions in the three germ layers of the gastrula become segregated from each

Fungai, introduction in fungai

introduction in fungai

How water balance take place in human body, How Water Balance Take Place in...

How Water Balance Take Place in Human Body? The amount of fluid in the body is tightly controlled because imbalance can be devastating. In a normal individual, the maintenance

What is the significance of the -r group, Q. What is the significance of th...

Q. What is the significance of the -R group (variable radical) in an amino acid molecule? The -R group, also known as lateral chain, is the variable part of the amino acid mole

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd