End-plate potential

Okay kiddo, so you know how our muscles move our body, right? Well, there's a special connection between our nerves and our muscles that lets our brain tell our muscles when to move. This connection is called the neuromuscular junction.

Now, at the neuromuscular junction, the nerve sends a special chemical called a neurotransmitter to the muscle. This neurotransmitter is like a message from the nerve to the muscle, telling it to move.

When the neurotransmitter reaches the muscle, it attaches to something called a receptor on the muscle. This is like a key fitting into a lock - when the neurotransmitter fits into the receptor, it opens up a channel in the muscle that lets positively charged ions flow in.

This influx of positive ions creates a little electrical signal in the muscle fiber, which we call the end-plate potential (EPP). The end-plate potential is like a tiny spark of electricity that gets the muscle fiber ready to move.

If the end-plate potential is strong enough, it can trigger a bigger electrical signal in the muscle fiber that makes it contract and move your body. And that's how our nerves tell our muscles what to do!