What is the part of brain cell that runs to and from nerves muscles in response signals brain?

The part of a brain cell that runs to and from nerves and muscles in response to signals from the brain is called the axon. The axon is a long, slender projection that extends from the cell body of a neuron (nerve cell) and transmits electrical impulses, called action potentials, away from the cell body to other neurons, muscle cells, or glands.

Here is a more detailed explanation of the function of axons:

1. Generation of Action Potentials: When a neuron receives a strong enough electrical stimulus, it generates an action potential. This is a brief electrical impulse that travels along the neuron's membrane.

2. Propagation of Action Potentials: The axon is responsible for propagating the action potential away from the cell body. This is accomplished through a process called saltatory conduction, where the action potential jumps from one node of Ranvier (unmyelinated region of the axon) to the next.

3. Synaptic Transmission: At the end of the axon, there is a specialized structure called the synaptic terminal. This is where the axon communicates with other neurons, muscle cells, or glands. When an action potential reaches the synaptic terminal, it causes the release of neurotransmitters, which are chemical messengers that transmit the signal across the synapse (the junction between two neurons) to the next cell.

The length and branching patterns of axons vary widely among different types of neurons, reflecting their specific functions and connectivity within the nervous system.