So inside the bone marrow we have monocides. They become microglia and then the microglia travels to the brain and they basically function as macrophages. And that means they basically engulf different harmful types of things such as some type of harmful debris. So if this is our debris floating around our neuron, the microglia basically eats up a debris and breaks it down so that it doesn't harm our neuron in any way. So these are the four major types of neuronglia glial cells, support cells found within our central system. Let's move on to our peripheral nervous system.