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.
Surgery and Prosthetic Phase Implants are uncovered Impression recorded Abutment placed Provisional prosthesis followed by Definitive prosthesis
Explain Avoidance of Shock in Nutritional Care? Loss of plasma proteins lead to decrease in blood volume (hypovolemia) and lowered red blood cell volume causing a potential dan
Explain the Adsorption or Binding Ability? Some fibre components have the ability to bind (adsorb) substances in the gastrointestinal tract. Wheat bran, guar gum, mannan and is
Briefly Explain about the Chromium? As you will go through this section, you will realize that compared to other minerals, the essentiality of chromium was recognized very late
Explain about the Oncogenic Viruses? Certain viruses that interfere with the functions of the regulatory genes have been identified. These viruses are called oncogenic viruses.
What are some biological examples in which lysosomic enzymes play a fundamental role? The remodelation of the osseous tissue, the function of acrosomes in sperm cells and the e
Mixotrophic nutrition
Explain about the Dietary Fibre? You are all aware that fibre is an important component in the structure of plants. However, fibre as a dietaiy constituent was considered impor
What is a Food Allergy (Hypersensitivity)? A food allergy or hypersensitivity is an abnormal response to a food by our immune system. As illustrated in Figure, this non-toxic a
explain glycolysis briefly? elaborate
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