And let me just add that there are two fluids in the petri dish.
Update: This one was easy, you were right it's Petridish with droplet embryo culture under mineral oil, just without embryos, because it was just a test (and opportunity to take pretty pictures:-))
And check out the answer to the last weeks challenge here.
And if you haven't seen them yet - challenge no. 1, 2 and 3.