Nerve conduction Physiology and Anatomy1

Simple Explanation of How axons work

1. Nerve Transmission :HB Chapter 9 Mechanism of Impulse travels along the axon once received at the dendrite

2. Salty Banana

3. Neurons as Electrical System studies demonstrated that cell membranes had a voltage across them and could produce direct current. The role of electricity in the nervous systems of animals was first observed in dissected frogs in Twitching Experiments the action potential was discovered Scientists of the 19th century studied the propagation of electrical signals in whole nerves (i.e., bundles of neurons) and demonstrated that nervous tissue was made up of cells, instead of an interconnected network of tubes (a reticulum).

4. Resting potential values in different types of cells ​ Cell types Resting potential​ Skeletal muscle cells ​ −95 mV​ Smooth muscle cells ​ – 60 mV​ Astroglia ​ –80 to –90 mV​ Neurons ​ –60 to –70 mV​ Erythrocytes ​ –9 mV​ Photoreceptor cells ​ –40 mV​

5. Resting Potential

6. Neurons as Electrical System the action potential resulted from a change in the permeability of the axonal membrane to ions. membrane conductance increases during an action potential.

7. Ion Channel

8. Neurons as Electrical System the action potential was generated as a threshold was crossed axonal membrane have different permeabilities to different ions; in particular, the crucial role of the sodium permeability for the action potential was demonstrated .

9. Voltage-Gated Ion Channel

10. Na/K Pump

11. Getting to -55mV

12. Repolarisation

13. Action Potential

14. Patch Clamping discrete ion channels that could exist in several different states, including "open", "closed", and "inactivated". Technique of patch clamping to examine the conductance states of individual ion channels.

15. Structural Studies In the 21st century, researchers are beginning to understand the structural basis for these conductance states and for the selectivity of channels for their species of ion,through the atomic-resolution crystal structures, fluorescence distance measurements and cryo-electron microscopy studies. The sodium–potassium pump was identified in 1957 and its properties gradually elucidated, culminating in the determination of its atomic-resolution structure by X-ray crystallography. The crystal structures of related ionic pumps have also been solved, giving a broader view of how these molecular machines work.

16. A word on synaptic transmission(Analog?)

17. Synaptic cleft

18. And Youtube! https://www.youtube.com/watch?v=dmQSP8uUwL8 https://www.youtube.com/watch?v=8-dZnp66t1Y https://www.youtube.com/watch?v=U2UnLoxMjAM https://www.youtube.com/watch?v=TUoCQTwewVo&t=2s

19. https://phet.colorado.edu/en/simulations/neuron