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If you've studied computer science with mathematics in the 11th and 12th grades and now need to include biology for a specific purpose (such as pursuing a career in medicine or a related field), you must check if your school offers additional or supplementary biology courses that you can take as a private student or as an extra subject. Some institutions allow students to enroll in specific courses, even if they are not part of the regular curriculum.

In some regions, you might be able to appear for supplementary exams to add biology to your qualifications. This can vary by board and location, so you should check with your local education authority or school.