In familial hypercholesterolemia, individuals homozygous for the allele causing the disorder completely lack receptor while individuals homozygous for the normal allele are phenotypically normal. this is an example of

a) codominance

b) epistasis

c) incomplete dominance

d) complete dominance

The right answer is C.

Incomplete dominance is when hybrids of the F1 generation have an intermediate phenotype (between the two phenotypes). That is, in the case of familial hypercholesterolemia, if the subject is heterozygous it will have 50% functional receptors compared to a healthy homozygous subject.

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.