Part 11.Fraternal is when there are two eggs and two eggs. Identical is when there is one egg and one sperm that gets split after fertilization.2.The original DNA needs to be identical3.Whether it's environmental or their genes.Part 21.Mutations and the different genes in other's bodies. Meiosis recombination2.It's inherited. Hereditary.Part 31.it has nucleotides and it's a double helix. it's wrapped around histones.2.mutations such as uv light on the skin constantly, living in a house with all smokers causing you to probably have trouble with your lungs.