How are signals transmitted in the nervous system?

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I have a presentation on the nervous system and this part just really confuses me.

In: Biology

2 Answers

Anonymous 0 Comments

How in depth are you looking for? I’ll try to explain a nerve.

A nerve is basically a bundle of neurons, each neuron is basically a tube. The tube is full of holes with gates on them that open and close in response to the charge of particles inside and outside the tube. When a signal is initiated, eg. you prick your finger, the trauma causes the gates on that end of the tube to open. When they do, the particles (ions) on the outside flow inside because there are a lot of them outside and not a lot inside.

Ions are charged particles, so when they flow in, there is a change in the electromagnetic situation around the membrane. (tube wall) The next gates over along the tube open because there is a piece in them that is pushed around by changing charges, and this unlocks the gate. More ions flow in and trigger the next section of the tube and so on.

It’s important to remember that one neuron carries a signal from your spine to the end of your toe; it’s not a chain of them. One comes from your brain down the spine and passes a message to the next neuron, which talks to the toe. How does it pass the message? I’m glad you asked.

When the “wave” of opening gates reaches the end of the tube, the wave triggers a release of chemical signals (neurotransmitters) which pour out the end of the one neuron onto the next. The next neuron has gates that don’t respond to changing charges but instead open when these chemical signals hit them.

**This is among the most difficult concepts in biology that I’ve had to wrap my head around, so the above is the way that I like to understand it. I can try to be more scientific if you like.**

Anonymous 0 Comments

Its a surprisingly elaborate process. Here is a rough sketch of how it works:

Cells talk to each other by releasing chemicals that the other cells detect. This is very slow unless you want to talk to the cell right next to you, so it isn’t good for the nervous system.

To get around this neurons are very long and can quickly send a message down the length of their own bodies. When neurons get a chemical signal they use electricity to quickly signal their other end about it.

So the message is sent in long hops down the length of the neurons with a lot of little pauses to move chemically from one neuron to another.