Does hard disk continue to run while sleeping?
It will almost never run while the computer is sleeping. Sometimes when you put the computer to sleep, the disk will run for a short time while doing "housekeeping". There are also options in the Settings for waking from sleep (thus starting the hard drive) for network access.

Closing the lid of a macbook will try to get it to sleep, but it may not always go there. If it does successfully sleep, then your drive should be inactive.