Income Exclusion Rule. DEFINITION of 'Income Exclusion Rule'. A rule that sets aside certain types of income as nontaxable. There are many types of income that qualify under this rule, such as life insurance death benefit proceeds, child support, welfare and municipal bond income. Income that is excluded is not reported anywhere on Form 1040.
Ancestral vs derived alleles. An ancestral allele or an ancestral trait (depending on whether you look at the phenotype or a t the genotype) is the trait/allele that was carried by the common ancestor of the taxon you consider.
Blood Type Genetic Basis: In genetics, blood type gene has two alleles, each allele has genotype A, B or O. The A and B are dominant, and O is recessive.So allele A combined with allele O is type A. Similarly, BO is type B, AA is type A, BB is type B, OO is type O, and AB is type AB.f both parents have type A blood, then the alleles could be AA or AO, thus the allele A frequency is 75%, allele O frequency is 25% for both parents. So the chance of alleles OO is 25% Ã 25% = 6.25%, alleles AA is 75% Ã 75% = 56.25%, alleles AO is 75% Ã 25% = 18.75%, alleles OA is 25% Ã 75% = 18.75%.