![]() When the chemical impulse from the motor neuron hits the muscle, it causes to muscle fibers to rachet past each other, overlapping each other more, so that the muscle gets shorter and fatter. Muscles are made of long fibers connected to each other longways by a ratchet mechanism, the kind of mechanism that allows the two parts of an extension ladder to slide past each other and then lock in a certain position. When the impulse travels down the axon to the muscle, a chemical is released at its ending. When a motor neuron inside the spinal cord fires, an impulse goes out from it to the muscles on a long, very thin extension of that single cell called an axon. Single nerve cells in the spinal cord, called motor neurons, are the only way the brain connects to muscles. ![]() ![]() How does your body move? Does the brain send it messages? ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |