Alleles

• Homozygous means having two identical alleles, e.g BB
• Heterozygous means having different alleles, e.g Bb
• Recessive is the less common phenotype that only shows when both copies are present
• Dominant is the more common phenotype that always shows even if one copy is present
• define gene?


  sections of DNA on a chromosome
• what are alleles?


  versions of a gene
• define genotype?


  tells us the alleles present
• define phenotype?


  tells us the characteristics caused by the person's alleles