I think it is impossible to get the biology science pack, I got all other researches, did you leave it out or something?
To be honest, I've been heavily invested in another game project for some time now, and haven't had the will to maintain this game, unfortunately. I do appreciate you taking the time to report the bugs.
As far as I'm aware the biology pack should be unlockable under normal circumstances, as I've tested the entire research tree to completion multiple times. However, due to possible bugs somewhere in the game logic, there may be a situation where the biology pack requirements somehow get corrupted or otherwise soft locked. My apologies, I can understand how frustrating it must be to get so far and lose your progress. I will try to look into the bugs when I get time, but honestly I might forget or put it off. Feel free to look through the source code on GitHub, if you find any specific issues Id be happy to approve a pull request. It's all coded in lua, which if you know any programming is a very easy language to learn. Thanks for playing and bug reporting 🙏
You can add me on discord "Add me as a friend on Discord! Invite expires in 1 week: https://discord.gg/F63UqnxN" Alternatively my username is "archaicvirus." With the dot at the end. If you have any questions about the source code or the way tic80 works I can assist.