AP BIOLOGY

Detailed explanation-1: -Recessive alleles only show their effect if the individual has two copies of the allele (also known as being homozygous?). For example, the allele for blue eyes is recessive, therefore to have blue eyes you need to have two copies of the ‘blue eye’ allele.

Detailed explanation-2: -Recessive alleles only show the traits if the person has 2 copies of the same alleles. This is considered being homozygous, having the same 2 copies of alleles. If a person has 2 copies of the blue eye allele (both recessive) then the person would have blue eyes.

Detailed explanation-3: -Of these three genotypes, only bb, the homozygous recessive genotype, will produce a phenotype of blue eyes.

Detailed explanation-4: -So, if you have one allele for brown eyes and one allele for blue eyes (Bb), your eyes will be brown. (This is also the case if you have two alleles for brown eyes, BB.) However, if both alleles are for the recessive trait (in this case, blue eyes, bb) you will inherit blue eyes.

Detailed explanation-5: -Homozygous dominant-Two dominant alleles are inherited, and the organism has the dominant phenotype. Heterozygous-One dominant allele and one recessive allele are inherited, and the organism has the dominant phenotype.