Mendel's Genetics Dihybrid Cross

Dihybrid cross

Crossing two varieties that differ for two traits

Example: 1. Seed Colour 2. Seed shape

Purebred

Homozygous parents for a specific trait

Gametes

Haploid reproductive cells (pollen, ovule)

Independent assortment

F1 produces 4 types of gametes because of ….

Phenotypic ratio

Ratio of different physical traits in offspring

Mendel's Second Law of Independent Assortment

Both traits inherited independently due to random assortment

Monohybrid

Cross involving one trait with different alleles

Epistasis

One gene interferes (allows or prevents) the expression of another gene

Polygenic Inheritance

When multiple genes are responsible for the expression of a phenotype resulting in a gradient of phenotypes

Pleiotropy

One gene affects the expression of many different phenotypes

Mendelian Genetics

• Law of segregation

• Law of Independent Assortment

• Law of Complete Dominance

Non-Mendelian Genetics

• Incomplete Dominance

• Codominance

• Multiple Alleles

• Polygenic Inheritance

• Epistasis

• Pleiotropy