Overview and Objectives for Gene Expression Part 2

This lesson describes how changes in the DNA sequence of a gene can alter the synthesis of a protein and thus influence traits such as herbicide resistance.

In this lesson we will describe how changes in the gene can alter the gene expression process and influence traits in an organism. The specific example of ALS-inhibitor herbicide resistance is used to demonstrate the impact of genetic change on trait expression in a plant.

At the completion of this lesson you should be able to...

1.) Explain how a mutation in a single gene can control resistance to herbicides such as ALS inhibitors.

2.) Predict the impact of a specific mutation on gene expression and the eventual trait observed in a plant.

3.) Distinguish between the molecular and classical definitions of an allele.

4.) Describe the molecular basis of dominance or a lack of dominance between alleles.

Copyright 2003

Development of this lesson was supported in part by Cooperative State Research, Education, & Extension Service, U.S. Dept of Agriculture under Agreement Number 98-EATP-1-0403 administered by Cornell University and the American Distance Education Consortium (ADEC). Any opinions, findings, conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.