External Regulators<span>. </span>External regulators<span> are also </span>proteins<span>, but they react to stimuli from outside the cell. They direct cells to either speed or slow the cell cycle based upon outside conditions. For example, one </span>protein<span> reacts to molecules on the outside of a neighboring cell. </span> I hope this helps out for you
they are not specialized, they can divide and renew themselves for long periods of time, and I think the last one is they have the ability to become more than one cell type
