February 7, 2016 Journal: Why do you and your siblings have different traits even though you have the same parents?

Genetics: Genotype & Phenotype

Determined many rules about basic genetics Gregor Mendel Determined many rules about basic genetics

Phenotype vs. Genotype Phenotype: the physical appearance of a plant or animal because of its genetic makeup (genotype) Genotype: genetic makeup of an individual

Genotype Gene: a specific region of a chromosome which is capable of determining the development of a specific trait; composed of DNA Allele: a pair of genes located at the same place on a homologous chromosome

Traits are controlled by genes Dominant genes: those that mask the presence of other corresponding genes Recessive genes: those whose physical expression (phenotype) is masked when in the presence of a dominant gene

Heterozygous vs. Homozygous Heterozygous- when a plant or animal has two genes for different traits Homozygous- when a plant or animal has two genes for the same trait

Dominant/Recessive Traits Whenever you have a dominant allele the dominant allele is expressed The recessive trait will only be expressed if there are two recessive alleles

Codominant Traits When both alleles are observed on the organism

Incomplete Dominance When both alleles mix together to form the appearance of the trait on the organism