>> |
Anonymous
Cells reproduce through a process called mitosis (splitting in half). An embryo starts out as a single cell, then rapidly divides until there are enough cells to form a whole body. Unfortunately, most cells are hard coded to divide a certain amount of times before they begin breaking down (notice that humans usually start getting sick at around 40 or older).
That's why small dogs live longer. Because their cells don't have to reproduce that much during the growing process, which adds extra years to their life. On the other hand, big dogs have to grow more mass (bigger organs, bones, etc) so their cells have to divide more often than a smaller dog.
|