Since it is the hearts job to pump blood throughout the body of the organism, the circulatory system would fail and the entire organism would suffer if the heart cells stopped working properly.
Density is a derived unit because it's not reported as a pure unit. (A pure unit would be something like kilograms or meters.) In contrast, the units for density are kg/m3. Density is the ratio of mass to volume; mass has the unit 'kilograms' (kg) and the unit for volume is cubic meters (m3).
Density is an intensive property, which means the amount of the material is irrelevant. The density of a substance is constant.
Chromosomes are the homologous chromosomes that cross over
