Jeb Sawyer spaketh...

making a tabletop out of 1" cherry on top of 1" MDF. I am going to

Brian already answered your other question, let me add that 1" cherry will
be plenty thick for for a desk under normal loads, the MDF won't be
necessary.

I'll also say that although the biscuits aren't necessary, they will make
glue up much easier and getting a good glue up will make finishing much
faster/easier. If you have a biscuit joiner, use it; if you don't have one,
don't buy one.
--
McQualude