Since at any moment a neuron is likely to have thousands of neurons releasing neurotransmitters at its surface, how is neuronal activity (to fire or not to fire) determined?

Video transcript

Hi, everybody. Welcome back. Our next question says glutamate can cause depolarization of the post synaptic neuron thus making it more likely to fire an action potential. Glutamate is therefore considered A or N A inhibitory neurotransmitter, B, excitatory neurotransmitter, C, active neurotransmitter or D passive neurotransmitter. Well, we kind of our, our question here sort of gives us a pretty big clue as to what it will be called. Reminding us that causing depolarization of the post synaptic neuron makes it more likely to fire an action potential. So it is excitatory. So choice B, excitatory neurotransmitter is our answer. We know that the post synaptic neuron has to undergo depolarization to fire an action potential. So if the neurotransmitter causes this to happen or reduces the charge differential, then it makes it more likely that an action potential will be generated as the threshold is lowered. Choice A inhibitory neurotransmitter, it would be a neurotransmitter that makes it less likely to fire N A P and action potential. And that's because it usually causes hyper polarization. So it causes that charge differential to become greater, thereby raising the threshold to generate an action potential. So, inhibitory neurotransmitter is exactly the opposite of what glutamate is. And then choices C and D active and passive neurotransmitter are not real terms for anything. So they can be eliminated because they're just not the real names of anything. So again, glutamate which causes de polarization of the post synaptic neuron making it more likely to fire an action potential is choice B an excitatory neurotransmitter. See you in the next video.