Are my chances at Stanford ruined?

Hello!
I am currently a junior and hope to apply to Stanford and several other prestigious schools next year. I am deeply interested in biology and although my extracurriculars aren’t fully developed yet, I will be competing in renowned competitions such as USABO and Siemens, and I am also doing a cancer-related research project. However, there is one major flaw in my resume: last semester, I received a B in a biology course. I attend a highly rigorous school and this class is known to be one of the most difficult offered, but I still feel like this is inexcusable. Do I still have a shot at Stanford, Ivy Leagues or equivalents?
Also, quick question: Do colleges see +/-s on your transcript? I.e. is there a difference between an A and an A-?
Thanks!

Btw, I am an Asian female from an urban area, so no advantages there

The one B did not shoot your chances, you’re fine. If you get rejected, it won’t be because of the B

My kid had a B+ in biology AP and Calculus AP. In fact, he had many A-s. Got into Stanford REA. ORM male. Don’t sweat it. That will not be the reason you get in or denied. To be honest, if he had a tougher teacher for biology, he might have gotten a lower grade than a B+. But the important thing is he still took AP Biology even when he knew he might get a B to find out if he liked biology; he did not.

Agree, if you don’t get into Stanford, it’s not because of a B, it will be because your application wasn’t compelling enough. Every elite college uses a holistic approach. They look at your interests, grades, standardized test scores, essays, and recs. It all has to tell a story. Carry on. and Good luck! There are a ton of great colleges out there, not just the farm.

Holistic applications, that B won’t hurt you. Relax.

If you are an ORM like my kid was, always apply to some Honors Colleges in state colleges which might even consider you as an URM and give you a nice merit scholarship. With all due respect to Stanford, don’t think you will not succeed if you don’t go to Stanford. There are many different ways to skin a cat. Problems in life crops up no matter which college you attend or wherever you are. It’s something you have to learn to deal with patience, fortitude, creativity and character.

Like everyone else is saying, one B won’t affect your chances.