Q: can i mirror my macbook pro to the appletv

About AirPlay and Airplay Mirroring

AirPlay Mirroring requires a second-generation Apple TV or later, and is supported on the following Mac models: iMac (Mid 2011 or newer), Mac mini (Mid 2011 or newer), MacBook Air (Mid 2011 or newer), and MacBook Pro (Early 2011 or newer). For non-qualifying Macs you can try using Air Parrot.

Several Apple Articles Regarding AirPlay

Apple TV (2nd and 3rd gen)- How to use AirPlay Mirroring

How to set up and configure AirPort Express for AirPlay and iTunes

About AirPlay Mirroring in OS X Mountain Lion

iTunes 10- About playing music with AirPlay

Troubleshooting AirPlay and AirPlay Mirroring

Using AirPlay

Thanks to the $15 Beamer, AirPlay streaming is still possible on Macs  that do not support Airplay and mirroring.

Another solution is the Air Parrot.

See > http://support.apple.com/kb/HT5404

AirPlay Mirroring requires an Early 2011 or newer MacBook Pro and OS X Mountain Lion. You say that you are using OS X Lion so, if you have a supported computer, just make a backup, open App Store and purchase Mountain Lion. After upgrading, you will see the AirPlay icon on the menu bar and on System Preferences > Displays.

If you haven't got a supported computer, download AirParrot to stream the computer to your Apple TV > http://www.airparrot.com