If the cells in our body are replaced every 7 to 10 years, why cant it roll itself back into a position where it worked better than it does now?

Question

For example: Someone has a disease, why cant the body just reset itself to how it was before it had the disease to get rid of the negative effects?

In: Biology

Answer 1

Ever use a copy machine? Like one of those monster Xerox machines from the 80s?

First copy is pretty good right? Well let’s say you toss the original. So you make another copy of the copy. And it’s pretty good too. So you keep making copies like that. Maybe after a while a hair, or a little dirt gets on the copy. It’s no big deal though because you can still read it just fine. Then maybe the paper gets a little crease and you lose a bit of a line. Oh well, you still can get the general idea. And on it goes. Eventually that copy is pretty much so full of smudges, blurred out words, and other errors that it’s basically worthless.

Well that’s your cells as they divide. The words on the sheet are your DNA. Eventually the DNA gets smuded and the new cells don’t have anything but the crap DNA to copy