AP BIOLOGY

Detailed explanation-1: -A dominant allele is denoted by a capital letter (A versus a). Since each parent provides one allele, the possible combinations are: AA, Aa, and aa. Offspring whose genotype is either AA or Aa will have the dominant trait expressed phenotypically, while aa individuals express the recessive trait.

Detailed explanation-2: -Codominance in humans is exemplified by individuals with type AB blood. A person inheriting the alleles IA and IB will have a type AB blood because IA and IB are codominant and therefore will be expressed together.

Detailed explanation-3: -To distinguish among different alleles, the abbreviation is followed by an upper-case letter (e.g., the rpoB gene encodes the subunit of RNA polymerase). Protein symbols are not italicized, and the first letter is upper-case (e.g., RpoB).

Detailed explanation-4: -In Mendelian convention, a capital letter is used to denote the dominant allele of a gene and a small letter for the recessive allele of the gene.