Android CPU usage

I think i have an issue with something running in the background. My android box sometime slows to crawl and either will not load selected items or just locks up. Is there a way to see what is running in the background and or to monitor how much cpu resources are being used. also is there a way to see what is being loaded on start-up? Most of the info I find addresses finding file and info on a laptop but not an android. Thanks in advance.