Hello,
It's not clear you're asking this question in reference to which exam, in case it's NEET you can get to know the weigtage as well as important topics by visiting the link provided below;
https://medicine.careers360.com/articles/neet-chapter-wise-weightage-and-important-topics
In case, your query is for other exam kindly mention in the comment box below so that we can help you with exact details.
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