Hello,

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If your board allows you to take up Biology as a subject after studying Mathematics in your 10th, you can surely study Biology in your 11th and 12th. Most students who aspire to become doctors study Biology even after B.Tech or B.Sc. And what you studied is Basic Mathematics and so understanding Biology will not be that difficult. Biology is a theory subject and if you can read and understand the topics, it will be easy for you relatively more than Mathematics. And the scope for Biology is wide because of the various options that you have at various stages. So do not worry about taking up Biology at your 11th and 12th even if you studied Maths in your 10th.