Â· 4 years ago. A mutation is a change in the genetic material of an organism. We are made from trillions of cells, each with a nucleus composed of DNA â a set of instructions that tells the cell what to do. Cells copy themselves with astonishing accuracy, but every now and then a piece of code is copied incorrectly.
Identical (or monozygotic) twins happen when a fertilized egg splits into two separate babies-usually within the first twelve days of Mom's pregnancy. After twelve days, the egg may not split entirely and result in conjoined twins.
Answered by The Community. Making the world better, one answer at a time. Fraternal twins can occur when the mother's ovaries release two eggs at the same time instead of one. If the eggs are fertilized, then fraternal twin embryos will develop.ince they came from o â¦ nly one egg and one sperm, their genes will be identical. Fraternal twins are two children born of two eggs and two sperms, each of them developing into a full organism.