Myelinated fibre, Biology

Assignment Help:

Myelinated fibre

Axon is a relatively long process (also quite often referred to as nerve fibre) and can be considered as functionally specialised for conduction of excitation over considerable distances. In vertebrates the axons of high velocity neurons are covered by insulating sheaths of lipid containing myelin. This myelin is made up of special glial cells -the Schwann cells. The myelin covering is not continuous. There are tiny uninsulated gaps between adjacent Schwann cells. These are the-nodes of Ranvier. The myelin covering and nodes of Ranvier help accelerate the speed of conduction of impulses by a mechanism which we will discuss later. The terminal part of the axon branches, terminating into small ramifications whose tips form end knobs which synaptically contact with other nerve cells. In the end knobs are present characteristic structures called synaptic vesicles which contain and store chemical substances called neurotransmitters.

349_Myelinated fibre.png

Figure: Myelinated fibre

The diversity in neuron form, however so much that is there can be many variations from the generalized description given above. For example, the nerve cells called amacrine cells found in retina contain processes without a demonstrable axon.


Related Discussions:- Myelinated fibre

Management for poisoning and overdose, Management  for Poisoning  and Ove...

Management  for Poisoning  and Overdose: The following data should be obtained at the time of initial contact.  Phone Number:  getting the caller's telephone number  is n

The halstead-reitan neuropsychological battery, The halstead-reitan neurops...

The halstead-reitan neuropsychological battery The beginnings of the battery can be traced to the special laboratory established by Halstead in 1935 for the study of neurosurgi

Ross operation-surgical techniques, Ross Operation :  In this technic...

Ross Operation :  In this technically demanding operation, the aortic valve is replaced by patient's own pulmonary valve (autograft) and a pulmonary or aortic allograft (homo

Determine the causal factors of nervous system, Determine the Causal factor...

Determine the Causal factors of nervous system Although, the brain and spinal cord are surrounded by tough membranes, enclosed in the bones of the skull and spinal vertebrae, a

Material basis of primitive life, Material Basis of Primitive Life: In ...

Material Basis of Primitive Life: In  the primitive society, human beings invented tools for catching animals, and for collecting, transporting and even preparing food.  They l

Which type of plant tissue is cork, Which type of plant tissue is cork? ...

Which type of plant tissue is cork? Cork, the material, for example, used to cap wine bottles, is extracted from the suber of a special oak known as cork oak.

Explain heterologous and homologous immunoglobulins, Q. What is the differe...

Q. What is the difference between heterologous and homologous immunoglobulins? Homologous immunoglobulin is the human from the same species immunoglobulin and In case of inocul

Explain hypertension in biochemical or physiological risk, Explain Hyperten...

Explain Hypertension in biochemical or physiological risk factors? The importance of elevated BP as a risk factor for CAD, heart failure, cerebrovascular disease and renal fail

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