Hi  student,

Yes you can study biomolecules before studying organic chemistry.

The reason of selecting it  is because there are no such concepts in this chapter which requires some prior knowledge of organic chemistry  but a little knowledge is important like the nomenclature of the compounds  their characteristics, groups etc.

So you can study it before organic chemistry but it will retain and understand more better wjen you complete your organic chemistry portion of class 12th.

Hope this answer helps you.

Thank you and very good luck!!!!!