Most multicellular organisms have two sets of chromosomes; that is, they are diploid. These chromosomes are referred to as homologous chromosomes. If both alleles<span> at a </span>gene <span>or locus on the homologous chromosomes are the </span>same<span>, they and the organism are homozygous with respect to that </span>gene<span> or locus.</span>
<span>The Correct answer is not shown. The correct answer would have to say Atom A has one proton than Atom B because in the question it says Atom A has an atomic number of 19 and Atom B has an atomic number of 20.</span>
