Why black shadows

Hello. I try to make flower on my first Cycle-project, but I dont understand why there is black areas on the petal. I use 2 sun-lamps. 1 on top and 1 in front ?
Do you know what missing.

Do you know what missing.
Your blend file so we can see your setup. Also include all relevant textures.

Have you uv unwrapped your mesh properly and applied your texture to these uvs ?

Thanks Richard for helping. http://www.pasteall.org/blend/19844
Yes I UV-mapped my petal, maybe not enough.

In material node editor your vector for image texture is set to Generated change it to UV

timi0 Thank you very much.
I try