Hi Vrushali,

The cutoff for BSC Biotech entrance is different for different universities some of the universities conduct BSc Biotech entrance exam. And some of universities give admission on the basis of 12th merit.
AIIMS Biotechnology Entrance Test
Jnu (Jawaharlal Nehru University) Combined Biotechnology 
Entrance Examination
CBCEE (Combined Biotechnology Entrance Examination)
DU (University of Delhi) Biotechnology Entrance Examination.
Qualifing mark for these exams about 33% ,if u score well enough then your chance's for admission are strong.

Hope this helps you