Original: The reproductive purpose of the penis is to enable sperm to be carried from the testicles into a woman 's body so that a sperm can fuse together with the woman 's ovum ( egg cell ) to form a new cell that will later grow into a baby .
Simplified: In reproduction the job of the penis is to carry sperm from the testicles into a woman 's body so that a sperm can join together with the woman 's ovum ( egg cell ) to form a new cell that will grow into a baby .