Medicine & Health Sciences Entrance Exam

No, its not like that. Students of class 12th also appear medical entrance examination and got selected also. But, you need to be very good at academics.

NCERT textbooks are must for NEET. You need to cover thoroughly the portion of 11th and 12th. Apart from that, you need to solve a good number of MCQs which will definitely boost your confidence up.

NEET examination is the only gateway for admission into MBBS and BDS courses in India. There's no other option. So you need to appear NEET only. Details are available at:
cbseneet.nic.in

482 is a very good score for MBBS as well as BDS. You may get government MBBS seat depending on your domicile state. But chances are less. You can get government BDS.

To qualify for admissions in MBBS/BDS seats in government, private and deemed medical colleges/universities in India, a candidate belonging to unreserved or general category needs to score a minimum of 50th percentile in NEET 2017, while, candidates belonging to SC/ST/OBC, the minimum percentile to obtain is 40th.

NEET is a national level undergraduate medical entrance exam organised by The CBSE. NEET is conducted for admissions to MBBS & BDS programmes that are offered by different medical & dental colleges in all over India. There are a total of approximately 426 MBBS Colleges. Total of approximately 63835 medical seats which are available for aspirants who clear the NEET exam 2017. At the end of NEET 2017, the MCC would be conducting the counseling for the 15% All India Quota Seats. The counseling for the remaining 85% of the seats in Government and private medical colleges would be done by the state counseling boards.

In NEET 2016, the marks range for unreserved category under All India Quota seats was 685 to 468.

B.Sc in biotechnology would be a better choice.
Well, both the courses are good. You can opt for B.Sc in microbiology, forensic Science, etc.
Good luck.

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