Hey guys! Today I'm gonna talk about how neurons cause muscle contractions through analogies!
This school bus is like a neuron! When the action potential reaches the front end of the bus, the doors open, releasing these chicks (ACh neurotransmitters).
These chicks are like ACh neurotransmitters that are released from synaptic vesicles! They bind to the door knob, which is like a ACh receptor. Doing this causes the door, or the sarcolemma, to open, allowing the chicks' mice friends, known as sodium ions, to enter the house, which represents a muscle cell. A party's about to start!
These mice (sodium ions) cause depolarization in the muscle cells, which travel through the hallway (T tubules), causing the sarcoplasmic reticulum, represented by these rooms, to release my squirrel friends which represent calcium ions and they are ready to party!
The party's getting started, but my friend myosin, represented by the dragon, is sad and looking for a hug from his friend actin, represented by the monster. But there's a big problem! Myosin is blocked by a door (tropomyosin).
Luckily for Myosin, the squirrels (calcium ions) are wild partyers and latch onto the door knob, which represents the protein troponin, moving the door (tropomyosin) out of the way. Now myosin is able to hug actin. Through this process, in a muscle cell, myosin heads latch onto binding sites on actin filaments to cause muscle contractions.