Iphoto and Iphone/digital camera don't communicate anymore. Any suggestions?

My iphone, my digital camera and iphoto on my Mac Book Pro don't seem to talk to each other anymore. I plug the devices into my computer and they just don't show up. When I sync my iphone with my Mac ALL 3500 photos from iphoto go onto my iphone (which I don't want) but the pics from my iphone I WANT to have saved in iphoto are not being transferred. Does anyone has a suggestionof what's going wrong? Thank you very much in advance for a reply.