PLEASE PLEASE HELP!!

picture riddles

Explanation:

1.people by me to eat but never eat me

2.i am always infront of you but you never see me

3.more you touch me harder i became what am i

4.i have hearts but no other organs what am i

5.i am the only organ that named by my self.

answer; i believe that the correct answer is ( troxel v. granville);