Biology is my weakest subject yet I easily put the most work into it

I can't get over a 5 in it even with excessive revision - for some reason I find it absurdly hard to remember anything eg. about the heart or palisade cells for example I just can't remember

I don't really want to make flashcards as it's not long till the exams and considering if I were to do it for everything I didn't remember it would take ages.

any tips on how to remember it as understanding isn't the problem - (my average grade in my mocks was 7.2 and I believe I can get an average grade above 8 in the actual thing)