system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:If we regenerate new skin cells, why/how does our skin wrinkle?
gpt
ELI5: As you age your skin becomes deficient of natural molecules that help your skin look young (collagen, which makes your skin more firm, glycosaminoglycans which provide water to your skin, and elastin which causes your skin to snap back into place). The combination (or rather lack of) of these compounds cause your skin to fold and dry out, also known as, wrinkling. 

Bonus Note: Skin cells that aren't wrinkled and skin cells that are look identical under a microscope.