Moelypoly,
I was told by my consulate, that I can replace the abstract of a graduation thesis with the abstract of one of my lab reports, which I'm sure you should have plenty. I normally don't even write abstracts for a lab report, but sometime, I have to write a "formal" lab report, which includes an abstract. So I simply just used the abstracted of one of my formal lab reports. Honestly, I don't the the abstract is very important at all. They won't even ask to see your thesis or lab report. Seems like its just a formality.
Is it worth applying? haha, trust me it is. I didn't have any research experience either, just lab experience that came with my degree. I'm sure research experience would help, but it isn't required. The most important part of this application process will be your research proposal and interview.
Oh, and not to be mean but, they won't care if you are from an ivy league school or not. But I'm sure your experience will help you a lot. good luck~