Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
How action potentials carry information...
A presentation for an A2 Biology lesson, as part of the topic of nerves.
Transcript of How action potentials carry information...
Alex is AWESOME! Dan SMELLS! How action potentials carry information... Alex Lea (Assisted by Dan Timmins) If a stimulus cells in the retina of the eye is received, it will be interpreted as light (even if it isn't). The top graph shows the response to a strong stimulus, and the the bottom graph the response to a weak stimulus. The method for doing this actually also very simple. It is deduced from the position of the sensory neurone bringing the information. So, that's it... Any questions? What's the problem with this? When your sensory neurones are stimulated, an action potential is generated. However, the strength of this action potential is invariable. The All or Nothing Principle For example... Shown graphically... Action potential Generated Strong Stimulus Weak Stimulus Strong Stimulus High Frequency Signal Weak Stimulus Low Frequency Signal Generated This states that the strength of stimulus has no effect on the size of action potential. Either an action potential is generated, or it is not. This is known as the all-or-nothing principle. If the strength of action potential doesn't vary with the strength of stimulus, how can we tell the difference between a strong and a weak stimulus? What the body does is actually really simple. Instead of varying the strength of the action potential, it varies the frequency. More neurons stimulated. Both peaks have the same amplitude, because both action potentials have the same strength, but they have frequencies. Now that the strength of the stimulus has been established, the brain needs to ascertain its nature... So, if the eyes were to receive another stimulus, such as pressure, it would still be interpreted as light. That's why when you rub your eyes, you "see" patterns of light.Full transcript