Your SlideShare is downloading. ×
0
Neurons
Neurons
Neurons
Neurons
Neurons
Neurons
Neurons
Neurons
Neurons
Neurons
Neurons
Neurons
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Neurons

1,415

Published on

0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
1,415
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
46
Comments
0
Likes
2
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide
  • http://thepluripotent.com/wp-content/uploads/2009/02/02-25-09-neurons-confocal-mu1a-dcx.jpg
  • http://factoidz.com/images/user/neuron.jpg
  • http://factoidz.com/images/user/neuron.jpg
  • http://www.mindcreators.com/Images/NB_Neuron.gif
  • http://pdginnovates.files.wordpress.com/2010/05/neuron.jpg
  • http://faculty.irsc.edu/FACULTY/TFischer/AP1/resting%20membrane%20potential2.jpg
  • http://www.northernhighlands.org/712410710134232943/lib/712410710134232943/General/Neurotransmitters.gif
  • http://www.morphonix.com/software/education/science/brain/game/specimens/images/neurotransmitters.gif
  • Transcript

    1. Neurons FOS 3 Infectious Disease Unit
    2. Neurons <ul><li>Your body uses chemical signals to send messages from one part to another </li></ul><ul><li>But if it only used chemical signals it would be way too slow </li></ul><ul><li>A quicker way is electrical signals! </li></ul>
    3. Structure of a Neuron <ul><li>Dendrites- the “antennae” of the neuron, receive information from other cells </li></ul><ul><li>Axon- a long extension of the cytoplasm that conducts nerve impulses. </li></ul><ul><li>Axon Terminal- end of axon. Nerve impulse leaves from axon terminal </li></ul><ul><li>Cell Body- main part of cell </li></ul>
    4. Structure of a Neuron <ul><li>Myelin Sheath </li></ul><ul><ul><li>Fatty outer layer around the axon </li></ul></ul><ul><ul><li>Causes nerve impulses to move faster </li></ul></ul><ul><ul><li>Not all neurons have it </li></ul></ul>
    5. Neuron Function <ul><li>Neurons have an electrical charge that is different from the charge of the fluid that surrounds them. </li></ul><ul><ul><li>This difference is called the MEMBRANE POTENTIAL </li></ul></ul><ul><ul><li>This depends on the concentration of ions inside and outside of the neuron cell </li></ul></ul><ul><ul><li>Membrane potential is measured in units called Volts </li></ul></ul>
    6. Membrane Potential <ul><li>Ions diffuse across a neuron’s cell membrane through special proteins called voltage-gated ion channels . </li></ul><ul><li>The channels are for specific ions </li></ul><ul><li>The channels are voltage-gated because they are open or closed depending on the membrane potential. </li></ul>
    7. Resting Potential <ul><li>When a neuron is not conducting a nerve impulse it is said to be at rest. </li></ul><ul><li>The membrane potential of the neuron at rest is called the resting potential. </li></ul><ul><li>Average is -70mV (inside cell is negatively charged compared to outside the cell) </li></ul><ul><li>At rest- Na+ channels are closed and K+ channels are open </li></ul>
    8. Action Potential <ul><li>A Nerve impulse. </li></ul><ul><li>A stimulus triggers a change, the Na+ channels open, Na+ ions then move into the axon. </li></ul><ul><li>Membrane potential increases to about +40 mV as the inside of the axon becomes positively charged. </li></ul><ul><li>This sudden change causes a chain reaction down the axon. </li></ul><ul><li>The action potential conducts rapidly down the axon toward axon terminals. </li></ul><ul><li>Na+ Channels close immediately after the action potential has passed. </li></ul>
    9. Action Potential <ul><li>http://www.youtube.com/watch?v=SCasruJT-DU </li></ul>
    10. Neurotransmitters <ul><li>When a nerve impulse arrives at axon terminals, it can be transmitted to other cells. </li></ul><ul><li>The junction at which a neuron meets another cell is called a synapse . </li></ul><ul><li>The cells do not touch one another at the synapse. </li></ul><ul><li>The signal must cross from one cell to another through neurotransmitters </li></ul>
    11. Neurotransmitters <ul><li>In the transmission across the synapse electrical energy is converted to chemical energy and then back to electrical energy in the 2nd neuron. </li></ul><ul><li>The chemicals used to cross the gap are called neurotransmitters. </li></ul><ul><ul><li>Some examples are: acetylcholine (in muscles) and glutamate (in the brain) </li></ul></ul>
    12. Neurotransmitters <ul><li>A neurotransmitter is released by exocytosis from the 1st neuron. </li></ul><ul><li>It diffuses across the gap and interacts with the channels in the 2nd neuron </li></ul><ul><li>It can either excite or inhibit the 2nd neuron. </li></ul><ul><li>It can open or close chemical-gated ion channels, this will change the membrane potential. </li></ul>

    ×