Why are identical twins identical?

1 Answer
Nov 23, 2016

They have the exact same genes.


After the sperm fertilizes the ovum, a zygote is formed. Eventually this will begin to grow, dividing in half again and again and again. However, twins result when at the first division, the two cells split and each grow on their own. So identical twins are exact genetic copies of each other; they're literally clones!