How to determine new records between two databases?

I have two databases with identical fields recording personal information. I have a database for the year 2005 and a database for the year 2010.

Each individual in these databases has a serial number associated with them.How would I determine the records that were new in 2010?

Sorry if this is a n00b question. I'm a total lightweight beginner in Access. I'm using Access 2010 on Windows XP.

Thanks!

:beer: