Hello dear student, 

If you are a domicile citizen of Tamil nadu then there is no point of applying under all india quota for Tamil Nadu Medical College. While you can apply under 85% state quota but if you are not a citizen of Tamil Nadu and if you haven't done your schooling for 5 years from that place or either of your parents are not from that place or have been staying in Tamil Nadu from last 10 years.  Then you can apply under AIQ . I hope this was helpful

Best regards Apoorva