Hello Anupama,
I suppose by medical stream you mean you had biology in 12th. And since you have not mentioned the course you want to get in, I'm assuming that it's BA (keeping in mind the most popular choices of DU and the keyword merit based).
So the basic eligibility for applying for DU Ba Hons is that candidates must have an aggregate of 45 percent marks in the qualifying examination. Which, you have. So yes you can apply for DU BA Hons on merit basis. (This answer is based on many assumptions due to lack of proper information from your side, if the assumptions are false, please comment below)
I hope this helps. All the best.
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