In an actin assembly and a microtubule polymerization, whenever an ATP/GTP cap is formed, what do you mean by "stabilizing" the microtubule or microfilament? Does it stop polymerization and prevent the microtubule or microfilament from continuing to grow or does it just prevent it from falling apart as simply as if the cap was not there? Does polymerization pause if a large ATP/GTP cap forms in such as way that hydrolysis can "catch up"