AP BIOLOGY

Detailed explanation-1: -Four alleles determine a rabbit’s coat colour: agouti (C), chinchilla (cch), Himalayan (ch), and albino (c). The order of dominance is C > cch > ch > c.

Detailed explanation-2: -An example of multiple alleles is coat color in rabbits (Figure 1). Here, four alleles exist for the c gene. The wild-type version, C+C+, is expressed as brown fur. The chinchilla phenotype, cchcch, is expressed as black-tipped white fur.

Detailed explanation-3: -An excellent example of multiple allele inheritance is human blood type. Blood type exists as four possible phenotypes: A, B, AB, & O. There are 3 alleles for the gene that determines blood type. (Remember: You have just 2 of the 3 in your genotype—1 from mom & 1 from dad).

Detailed explanation-4: -The coat colour of rabbits is determined by the C gene. The C gene has multiple allelic forms that lead to varied phenotypes. The different phenotypes for coat colour in rabbits are agouti (full colour), chinchilla, Himalayan and albino. The four common allele of C gene are C, cch, ch and c.

Detailed explanation-5: -An example of multiple alleles is the ABO blood group system in humans. Human gene I (I for ‘isohaemagglutinin’) exists in three allelic forms: IA, IB, and IO. IA and IB produce type A and type B antigens, respectively, on the cell surface of RBCs whereas IO (or i) is a recessive allele and does not produce antigen.