For IISER Admission,they conduct the admission in three channels:-

a)KVPY

b)SCB

c)JEE

Now if you opt for the SCB Channel,they have questions from 4 sets Physics, Chemistry, Mathematics and Biology. So if you have Biology in your 11th and 12th,that would be a plus point for you.For further details and to know more about the eligibility criteria please follow the link:-

https://www.google.com/amp/s/engineering.careers360.com/articles/iiser-admission/amp

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