Modes of inheritance There are more modes of inheritance than simple dominant-recessive with only 2 alleles

Co-Dominance Both alleles show at the same time Produces a third phenotype Example Black bear mates with a white bear = the offspring is striped or spotted White flower is bred with a red flower = the offspring is red and white spotted

Incomplete dominance Blend of alleles is shown Produces a third phenotype Example Black bear mates with a white bear = the offspring is gray White flower is crossed with a red flower= the offspring is pink

Multiple alleles and Co-dominance Occurs when there are more than 2 alleles for a trait Each individual can only have 2 alleles Can result in 4 different combinations Example Human blood type A, B, AB, O

Sex Linked Gene is carried on sex chromosomes Produces ‘carriers’ Females = XX Males = XY Produces ‘carriers’ heterozygous for gene Example Color blindness is housed on the ‘X’ chromosome Xc = not color blind X-c = colorblind