Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Conduction in Myelinated Axons
The myelin sheath provides insulation for the axon preventing movements of Na+ and K+ through the membrane. Therefore, if this myelin sheath was continuous no action potential would be generated. Fortunately, gaps or nodes of Ranvier occur in the myelin. Since the cable properties of axon can conduct depolarisations over very short distance (1-2 mm), the nodes of Ranvier must be close together (actually they are 1 mm apart). Studies have shown that the Na+ channels are concentrated at the nodes and absent from the regions between two nodes. Action potential therefore occurs only at the nodes of Ranvier and seems to leap from node to node. This is called saltatory conduction. The spread of depolarisation between the nodes is very fast and fewer action potentials are needed. Therefore, the rate of conduction is much faster than in unmyelinated fibres.
This peculiar structure and mode of conduction in myelinated fibres is responsible for the fast conduction of impulses in motor nerves of vertebrates even though the nerves are very thin. The greatest advantage of myelinated fibres comes from their smaller size and so a highly complex nervous system with high conduction velocities can occur without occupying too much of space.
How are grasslands classified? The Grasslands may be classified into steppes and savannahs. In a steppe prevailing vegetation is grass, as in the pampas of South America and in
1. Noise producing industries, railway stations, and aerodromes should be located away from the residential areas. 2. Check on the traffic in the residential colonies.
Thalassemia Thalassemias are the commonest hemolytic anaemias or disorder seen in children in India. This is characterised by deficiency in the synthesis of one of the norm
Guanotelism - Excretion Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4
How does the immune process that causes the hemolytic disease of the newborn take place? In a hemolytic disease of the newborn the mother has Rh- blood and this mother when gen
MALE REPRODUCTIVE DISORDERS Generally, about 5-10% of cattle bulls reaching sexual maturity would be suffering from poor reproductive efficiency or sterility. Crossbreeding ha
Explain what is Molds ? Zygomycota, or molds, are a type of fungus made of filamentous hyphae that grow on decomposing material. The molds actually aid in the decomposition pro
Meningococcal disease Meningococcal vaccine is recommended for adults and children >2 years old who are traveling to areas where epidemics are occurring, or to the "meningitis
What are the female pronucleus and the male pronucleus? The female pronucleus is the proper haploid nucleus of the egg cell. Male pronucleus is the haploid nucleus of the sperm
Q. What are the difference between plasma membrane and cell wall? Plasma membrane and cell wall is not the same thing. Plasma membrane, also known as cell membrane, is the exte
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd