I have a lg ks360 and i am confused.com!?

when i connect my phone to the computer to transfer photos i ahve taken the only photos it opens are those saved to the phone not my memory card that is my external memory card! y does the computer not recognise this because any time i even go to tranfer songs its says there is no free disk space but if it would add it to my memory cad it should? how do i get this?