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

Determine the improper occlusal scheme, Improper Occlusal Scheme This i...

Improper Occlusal Scheme This is an important cause of failure as the implant are more sensitive to occlusal trauma and leads to prosthetic failure and bone loss. The susceptib

Stabilisation - climax, Stabilisation - Climax The whole process of s...

Stabilisation - Climax The whole process of succession results in stabilisation of the vegetation which is now in complete harmony with the environmental complex of that plac

Evolutionary advantage of the occurrence of sperm cells, What is the evolut...

What is the evolutionary advantage of the occurrence of sperm cells and larval stage in the life cycle of sponges? The sexual reproduction in sponges, in addition to contributi

Discuss in brief about maxillary sinus, Discuss in brief about maxillary si...

Discuss in brief about maxillary sinus In normal conditions, the maxillary sinus maintains a close relationship with the alveolar ridge associated with second premolar and fir

Mitochondria, MITOCHONDRIA  (Singular-  MITOCHONDRION) These are cons...

MITOCHONDRIA  (Singular-  MITOCHONDRION) These are conspicuous, hollow  sac liked  cell organelles found in all eukaryotic  cells except  mature  red  blood  corpuscles RBC s

Totipotency and pluripotency, Totipotency and Pluripotency In the sta...

Totipotency and Pluripotency In the starting we said that the fertilized egg cell (zygote) has the capacity or potentiality to give rise to all kinds of cell types, like a bl

Endothelium derived constricting factor, Endothelium is a source of vasocon...

Endothelium is a source of vasoconstrictor factor also. The best characterized of these are the endothelins. Endothelium produces only ET1. Unlike NO, which is released rapidly in

Explain the direct surface agar plating method, Explain the Direct Surface ...

Explain the Direct Surface Agar Plating Method? In the direct surface agar plating method, molten agar is placed on to the surface to be assessed. Upon hardening, it is incubat

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