So.. if your bisexual and a scholarship's name is "gay and lesbian..." does that mean applying would be inappropriate, even if its under the general LGBT category? How do you know if you're excluded?
No, it's not. Many liberal organizations are not aware that we exist yet, or transgender people for that matter. Any non straight should apply for such a scholarship. The only caveat to that would be if it were specifically a lesbian scholarship, then cis or transmen should not apply, but obviously, bisexual cis or transwomen should still apply.
If you want to be absolutely certain you can always contact the sponsoring organization. Usually though, if they mean to exclude non-monosexual members of the LGBT community there will be very specific verbiage that does just that. In the absence of such a disclaimer I think any person who isn't straight can probably apply. Gay and lesbian is often used as a shorthand for the entirety of the rainbow tribe. A lot of organizations just prefer to keep it short for purely practical reasons. Some organizations tend to see bisexuals as a sort of a subset of gays/lesbians. Some things got their name at a time when there was just less awareness about non-monosexual identities. One example I can think of is PFLAG (Parents Friends and Family of Lesbians and Gays). They don't mention bisexuals in the name but their vision, mission statement, and strategic goals include them. They also have some of the better written resources on bisexuality that I have found. That's my long-winded way of saying, "Go for it!" If they didn't tell you that you can't it is probably safe to assume that you can. Good luck!