From DNA to Organism: A Study in DNA Function for the High School Biology Classroom

Module 2: DNA and genes

Lab Letter

Dear Biology Students,

            I understand that you have located a plant that does not look to be doing well but does not show any obvious reason why. I think I may be able to help you with your problem.

           As you have seen there are many different types of plants with many different phenotypes. Even within one species of plant there can be many different forms of the plant. The key to these forms is that not all of them are good; in fact, most of them tend to be bad for the plant. For example, a short plant is not as good as a tall plant, in most cases because the tall plant is better able to compete with other plants for sunlight to use in photosynthesis. It is obvious that your plant’s phenotype is not good. You just need to investigate what might cause the problems that you have observed in your Arabidopsis plants. 

            I have been working in my lab on Arabidopsis mutants, specifically on a mutation in a certain gene named AKT-1. Based on my research, I suspect that this mutation may have something to do with your plant’s poor performance. You just need to see if your plants have the gene mutation or not. If they do, this is probably what is causing their problems. The gene is about 900 base pairs (b.p.) long in its wild-type (functional) form. Your just need to see whether or not your plants have that 900 b.p. gene. You will need to use some DNA lab techniques along the way to answer the question so I included a set of techniques that might help you to answer the question. Good luck and thanks again for your help.


Dr. Berkowitz