I'm a resit candidate.I wrote the bio and chem exams and my invigilators told me that i was not required to write paper 3/2 when i received my results it showed that i was absent.  

if you're writing it for the first time, your labs will cover those grades.  If  you've written it before withing a period of 3 years, your labs will cover those also as i was told. otherwise, you have yourself an issue and you need to bring this up with your local ministry of education