Installed new hard drive in my MacBook Pro, and now computer won't start

My original hard drive in my MacBook Pro crashed about a month ago, and I took it to the Apple store to see what I could do. They couldn't repair it, and I would have to ship it off somewhere to have it repaired for what I've heard can be a costly amount. A friend of mine recently bought a new MacBook Pro, and while she was at the store, purchased a new hard drive, which they installed right then and there. She got to keep the original hard drive from her new computer, and sold it to me at a discount. I've installed the new hard drive, but when I start my computer, I get a gray screen with a "slash through a circle" logo, as if it's not reading anything at all. When I attempt to start my computer with my crashed hard drive, it would at least attempt to boot up and show a progress bar until it stopped loading. To me it sounds like the hard drive I bought from my friend is bad, but she had it swapped out at the Apple store, so I'm not sure what's going on here. Any help is appreciated.

Thanks