The atoms in chemical compounds are held together by attractive electrostatic interactions known as chemical bonds. Ionic compounds contain positively and negatively charged ions in a ratio that results in an overall charge of zero. The ions are held together in a regular spatial arrangement by electrostatic forces.
In the graph you can so that two of the shapes ae fully black, that means that they are color blind, the half colored ones means they are a carrier but they aren't color blind. So two males in the offspring are color blind.
