identifying cells brought in from another worksheet
 

I have an original Issues Log saved in Excel and receive updates via Excel
twice a week. I have my original on one worksheet and I'm pasting in the
update into the 2nd worksheet. My 3rd worksheet is filled with EXACT
formulas (not very efficient) and my 4th worksheet pulls in data from my
original and from the 2nd tab ONLY when it's different from the original.

My problem is, I want to highlight the cells that have come from the 2nd or
updated worksheet.

Thank you!