I read some where when you are young the skin cells are nice and smooth and elastic but when you get older the reason your face and skin get wrinkled is because it becomes hard and less elastic. Not sure why it get hard and less elastic?

Some thing to do with the human body that replace extracellular protein elastin with less pliable collagen? The build up of collagen and less elastic or less pliable collagen?

Also some thing to do with cells not dividing or dividing very slow because of telomere caps? That the telomeres have a cap and cells stop dividing or are dividing very slow because of the telomeres cap.

Not sure why people when they get older get thin hair or very little hair may be it is some thing to do with person DNA?