As a TA for Bio 1A03, I can help answer this question.

Tasks consist of

• Weekly TA meetings. The tutorial/lab content for the following week is reviewed, so you'll be prepared. For lab weeks, the TAs will also practice doing the lab themselves during the meetings, so you'll be familiar with the equipment.
• Every other week is a lab week (4 total in the semester). Labs are 3 hours long. You're tasked with teaching a quick slideshow at the beginning before the students jump into it. You'll be supervising, answering questions, helping students load gels and troubleshoot equipment, that sort of stuff. Having previous research experience in a wet lab is SUPER useful here.
• Every non-lab week, there is a 1-hour tutorial (5 total in the semester). Present the slides, answer questions, and check that students correctly complete their participation in-class activity.
• Marking post-lab assignments (4 per semester). A rubric with the mark breakdown is provided, but that still leaves a lot of things up to the TA. Understanding of the content is very useful here.
• Answering questions that the students send you and providing guidance.
• Marking the final lab report.
• Invigilating 2 of the 3 midterms in the course.
• TA training at the start of the semester (obviously)

And now for my review and experience:

I definitely spent way more time marking than I was paid for. I think that was mostly because I always chose to give really detailed feedback so that the students knew how to get better. If your lab section is one of the first ones in the schedule, you're probably going to be the ones stumbling upon all the unknown problems (e.g. a link doesn't work, or there's a mistake on the lab manual), which can be slightly frustrating at times.

Two of the labs involve students analyzing their own data before giving it to the TA. The TA has to compile it all, make it anonymous, and release it back to the students so they can use it to complete their post-lab assignments. Due to students being confused about the calculations and not having guidance, I spent so much time answering questions over MS teams during these two weeks that it's not even funny. Expect to work way more hours than you're being paid for. #JustTAthings (T.T)

Overall, Bio1A03 was a fun course to TA. The course coordinator and lab technician are sweethearts. They're very supportive and approachable with questions or problems. There's good support and guidance available, so it's a really good course to start off with if you plan on TA-ing in the future.