Giant nerve fibres, Biology

Assignment Help:

Giant Nerve Fibres

We now know that giant nerve fibres take place in the central nervous system of many polychaetes, oligochaetes, insects cephalopod etc. They are broader and longer as compared to the other, ordinary nerve fibres which are about 2 μm or so only in diameter. In the squid, they might attain a diameter of 700 μm or even more. Their size makes them ideal material for electrophysiological studies, like recording electrodes can be inserted inside the axons and action potentials measured. They are of immense benefit to the animal because, with the increase in diameter of the axon, resistance for propagation of action potential is decreased, while velocity of propagation is increased. They conduct for longer distances with fewer or no synapses that also further facilitate conduction. On the whole they are pre-eminently suited for rapid conduction. These Fibres are included in escape reactions of the animal. The squid for instance is rapidly propelled in water by expelling the water within the mantle cavity by fast and simultaneous contraction of the muscles of the mantle innervated by the giant fibres by using the principle of jet propulsion. The animal can escape from its enemies through this method within a fraction of a second.


Related Discussions:- Giant nerve fibres

Procedure for preparation of selective & differential medium, Procedure for...

Procedure for Preparation of Selective and Differential Medium Now prepare the MacConkey agar medium following the steps given herewith: 1. Weigh and dissolve all ingredient

Types of ecosystem, Types of Ecosystem Basically ecosystems are of two ...

Types of Ecosystem Basically ecosystems are of two types : terrestrial and aquatic. If you travel from plains to the mountains in the Himalayas, you notice significant changes

Dendrology, Dendrology : This is the study of all kinds of trees. Dendrolog...

Dendrology : This is the study of all kinds of trees. Dendrology we can also say it xylology it is the science or study of wooded plants like trees, shrubs, and lianas. There is no

What do you mean by synapses, Q. What do you mean by synapses? Synapses...

Q. What do you mean by synapses? Synapses are the structures that transmit the neural impulse between two neurons. When the electric impulse arrives the presynaptic membrane

#titlecylintreta.., Aiscommoncellismwhatsk question #Minimum 100 words acce...

Aiscommoncellismwhatsk question #Minimum 100 words accepted#

Formation of new membranes, Formation of New Membranes Divisions of t...

Formation of New Membranes Divisions of the egg or blastomeres raise the total surface area of the two daughter cells to be covered via membrane at every cleavage. The parent

Illustrate thallium scintigraphy, Q. Illustrate Thallium Scintigraphy? ...

Q. Illustrate Thallium Scintigraphy? It is often done with SPECT (single photon emission computed tomography) which further increases the sensitivity. However, a stress test w

What are the characteristics of thick gingiva, Characteristics of Thick Gin...

Characteristics of Thick Gingiva  Relatively flat soft tissue and bony architecture  Dense fibrotic soft tissue  Relatively large amount of attached gingiva  Thick und

Nervous system and nerve cells, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE

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