- Slides: 17
Genetics �Genetics is the study of how traits are inherited in offspring.
Genetics �Gene: Segment of chromosome (DNA) that codes for a trait
Genetics �Allele: Different form of the same gene. �Example: Skin Color (Color, Albino)
Genetics �Humans normally have two alleles for each gene.
Genetics �Dominant: Trait that gets expressed from dominant allele.
Genetics �Phenotype: Observable physical or behavioral trait
Genetics �Genotype: Genes (Alleles) that code for a trait
Genes and Traits part 2 �Homozygous: having the same forms (alleles) for a gene on both chromosomes. �Also said to be purebred.
Genetics �Homozygous Dominant = AA �Homozygous Recessive = aa
Genetics �Heterozygous: having different forms (alleles) for a gene on both chromosomes. �Also said to be hybrid.
Heterozygous = Aa, or a. A Genetics �Monohybrid Crosses �Gene: Albinism �Dominant Allele: A = normal skin color �Recessive Allele: a = albino
Heterozygous = Aa, or a. A Genetics �Cross a heterozygous individual with a heterozygous individual: Aa X Aa A AA Aa aa
Heterozygous = Aa, or a. A Genetics �Cross a homozygous dominant individual with a homozygous recessive individual: AA X aa a a A Aa Aa
Heterozygous = Aa, or a. A Genetics �Test Cross: Cross a homozygous recessive individual with an unknown (homozygous dominant or heterozygous): aa X A? a a A Aa Aa ? A? A?
Heterozygous = Aa, or a. A Genetics �The outcome determines the offspring. If half of the offspring are albino, then the unknown is heterozygous (Aa). a a A Aa Aa a aa aa
Heterozygous = Aa, or a. A Genetics �If all of the offspring have normal skin color, then the unknown is homozygous dominant. a a A Aa Aa