This lesson is an independent activity where students will determine mutations in sequences of DNA by comparing them with the data given.
Mutations in DNA can be very harmful. Some mutations are congential, meaning you have them at birth because you inherited them. Others can be brought on by some sort of environmental stress. For instance, the UV rays in sunlight directly affect DNA, and can cause it to mutate. Smoking can cause normal cells to turn cancerous, yet the way it does that has yet to be figured out. Mutations will lead to the production of inappropriate proteins that can no longer serve the function they are needed for. Other mutations can be tolerated due to the degeneracy of the genetic code.
Objectives:
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-Students will be able to review the codons of the genetic code.
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-Students will be able to identify which mutations are functional and which are not.
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-Students will be able to integrate the direct link between structure and function.
Introduction:
This lesson can be initiated with a statement about good mutations. Mutations in DNA has led to the vast diversity among all of us. Mutations in DNA can occur during meiosis, or formation of the gametes due to the chromosomes crossing over eachother.
Content:
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1. Review codons, and how they code for amino acids.
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2. Describe mutations, and how to detect them.
Methods and Procedure:
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1. Initiate lesson and describe mutations.
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2. Model example of how to find a mutation.
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3. Students will work independently on mutation worksheet.
Closure:
This lesson can be closed with a statement about the link between environmental stress and mutation. Describe why UV rays can be so harmful. The ozone layer blocks out these harmful rays, yet with the depletion of this layer, more of these rays are striking us down here on earth. What can be done to decrease your risk from these harmful rays?
Resources and Materials:
In Appendix F you will find the mutations worksheet, which is one way to present this lesson’s objectives.
Assignment:
Students could have a journal assignment where they are to respond to a question such as: A friend of yours likes to tan in the sun and in tanning salons. This person does not know about DNA and mutations. What might you tell this person?