Conduction of impulse, Biology

Assignment Help:

CONDUCTION OF IMPULSE -

IN NON-MYELINATED AXONS -

  • The impulse moves along the axon as local effect by altering the permeability of neighbouring Na+  channels and affecting every next channels in succession moving the effect ahead from axon hilllock to the axon terminal.
  • This is called stepwise or local circuit theory of transmission & is comparatively a slower conduction, generally found in invertebrates.

IN MYELINATED AXON -

  • As axon is insulated the impulse, generated at axon hilock can effect the Na+  channel only at the node of Ranvier where the axolemma is exposed, which means Na+  can cross the membrane only at these sites.
  • This effect moves quickly from one node to another i.e. saltatory transmission.
  • Velocity of transmission of impulse is a to       

                     - degree of myelination

                     - temperature

                     - diameter of axon, it is 1500 m in sea squid while in vertebrats only 25-35 m

  • The average valocity of conduction in frog is about 20-25 m/sec. while in mammals 100-200 m/sec.
  • The fastest in some nerves of human beings is upto 532 kmph.

648_nerve impulse.png


Related Discussions:- Conduction of impulse

Cellular respiration, Cellular Respiration: General Formula For ...

Cellular Respiration: General Formula For aerobic respiration (in the presence of O 2 ) C 6 H 12 O 6 + 6O 2 --> 6H 2 O + 6CO 2 + 36ATP (theoretical)

What are possible treatments available, What are possible treatments availa...

What are possible treatments available for a herniated disc injury?

Prevention - rheumatic fever, Acute GAS pharyngitis should be treated promp...

Acute GAS pharyngitis should be treated promptly by penicillin or other antibiotics. Indian Council of Medical Research (ICMR) recommends that all cases of pharyngitis must receive

Events after sperm and egg fusion, Events after Sperm and Egg Fusion ...

Events after Sperm and Egg Fusion The entry of the sperm into the egg activates the egg. The activation of egg results in two types of responses. (1) The early responses a

Oceanic islands, Oceanic islands are interesting and somewhat specialised b...

Oceanic islands are interesting and somewhat specialised biomes. Islands which have broken away from the main continents have similarity of flora and fauna related to the continent

Oxygenator- equipment of cardio pulmonary bypass , Oxygenator :   They serv...

Oxygenator :   They serve the function of lungs during extra corporeal circulation (ECC) - Oxygenation, removal of carbon dioxide and transport of gaseous anaesthetic agents:*The o

Flow cytometry, Ask que1. Design a 4 colour Flow cytometry experiment with ...

Ask que1. Design a 4 colour Flow cytometry experiment with an aim to identify B220-, CD3+, CD4+ (DOUBLE POSITIVE) AND B220+, CD3-, CD4- (DOUBLE NEGATIVE) cells. Select from the fol

Define the role of riboflavin in antioxidant activity, Define the role of r...

Define the role of riboflavin in Antioxidant Activity? Flavoproteins also have powerful antioxidant activity from their role as precursors to FMN and FAD. Among the FAD-requiri

Explain the sinus perforations, Sinus Perforations  The maxillary antru...

Sinus Perforations  The maxillary antrum can sometimes be inadvertently penetrated. Through careful pre-operative planning using radiographs, including axial scans, this compli

What is reverse osmosis, What is reverse osmosis? Give its one application....

What is reverse osmosis? Give its one application. Which two heart sounds are heard through the stethoscope when placed on the chest? When are these sounds produced respectivel

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