Turn on and off MacBook Pro Retina connected to a Thunderbolt Display monitor I would like to know if there is a way to turn on and off a Macbook Pro Retina connected to a Thunderbolt Display monitor when it is closed.

Should I open my MacBook Pro Retina each time I need to turn on my computer?

Is the only solution to not turn it off and putting it into sleeping mode?
You can bring up the power menu by pressing Control-Eject. You can also directly sleep (Command-Option-Eject), shut down (Command-Option-Control-Eject), restart (Command-Control-Eject), or turn off the display (Shift-Control-Eject) using the keyboard. You can also press any key to wake a sleeping mac.

There is no known way of turning on recent Macbooks via keyboard except for the power button.