Asking a prof to change my grade I got a B- in my biology course this semester and the day I received this grade I checked my requirements for a specific course I want to take next year and it said the minimum requirement was a B-. However when I checked it again the grade is now a B. I am off by 1 point. Can I ask my professor to change my grade?
As Brian says, professors aren't likely to give you a bonus point just so you can take the next class in the series. After all, there has to be a cut-off somewhere. As an anecdote, I have laughed with multiple graduate students about silly grade-grubbing attempts they're sent.

Most universities let you bypass prerequisites with instructor permission. Since you were so close to the cut-off; and it looks like the cut-off changed in the meanwhile, you might have better luck asking next quarter's professor if you can take her class anyway. In my experience, you might have to register later, which could be difficult if this is a popular course, but I would say you have a better chance with that then getting that 1 point out of the other professor.