Overview and Objectives - Basic Gene Inheritance

This lesson reviews the basics of gene inheritance. It compares plants that are homozygous, heterozygous, and hemizygous for an allele and how gene expression is affected by the dominance of an allele. It also explains how to use a Punnett square to predict genotypic and phenotypic ratios of offspring.

At the completion of this lesson, you should be able to:

• Describe the difference between a plant that is hemizygous, homozygous, and heterozygous for a trait.
• Explain how you could tell if a plant was homozygous or heterozygous and how allele dominance would affect this.
• Compare the expression of a dominant allele with that of a recessive allele.
• Describe a test to determine if a plant was homozygous or heterozygous for a dominant allele.
• Demonstrate the inheritance of transgenes using Punnett squares. Predict ratios of progeny phenotype and genotype.