Hey rebeccacar! Firstly, don't be so hard on yourself, those are some pretty decent sacs scores!
In response to your question of whether 35-40+ is possible- Definitely. Especially in a heavily exam-weighted subject like biology (sacs 40% exam 60%), it's your exam mark that really determines your score. Depending on what you do in the few months leading up to the exam, a 40+ is totally achievable.
Not advertising myself or anything, but feel free to read through my advice for doing well in bio if you haven't

(link below) . My overall sac average was below 90%, but I managed to make up for this due to some intense studying spaced throughout term 3 and 4, and ended up performing well on the exam.
If you aim for A+ like you said, 40+ is a reasonable aim. Good luck with bio!