UCL (University College London) Questions

I am a junior coming from a private school in the USA and was thinking of applying to UCL. Since my school has less than 75 students per grade, there are not many AP classes to choose from.

This year I could only take AP US History which I am taking and I will most likely get a 5 on the AP exam. Next year I am planning to take AP calc AB, AP Bio, AP spanish, and AP Physics C: mechanics. I already took my ACT and got a 31.

My question is: since AP physics is only half an AP according to UCAS that will mean I am taking 4.5 APs and not the 5 required for entry and is that ok?

Also is it ok that some of my APs are not related to the major I will apply for, which is biological sciences?

Finally, does UCL take SAT subject tests in addition to AP exams?

Thanks

I applied to UCL this year and was accepted. Your AP Physics seems to be fine, I did the same thing. Most of my APs were unrelated to my major (management) because there is no AP that necessarily covers it. UCL does take subject tests, AP tests, and all other SAT/ACT scores on the application.
One thing about UK schools as that they are really open to questions and clarifications to an application send through an email. If you get more SAT/ACT scores, you can always send it to them in an email and they will update your app.
The APs that you have taken so far seem great, but keep in mind that IB math is a bit higher than AP Calc AB. In the event that you are invited to an interview, I would suggest studying some advanced math topics.
Feel free to send a PM if you have more questions about the process.