Talking sex with children

So its spring and things are happening all around us. My 8 yr old daughter has noticed animals doing weird things. She has in the past expressed interest in babies and sex and how all that works. I'm not really sure if I'm ready or comfortable enough to explain it all but my question is.... is it too early to explain it to her and what or how much do I tell her? She's a very affectionate person an very curious as well. I want to be as open and honest with her as I can but I'm uncomfortable when it comes to sex and I don't know if shes still too young. Help please!!!