DNA MOLECULES
OBJECTIVE:
Students will design a three dimensional model of DNA to learn how nucleotides are formed.
MATERIALS:
Plastic straws, two different colors
Lucky Charms cereal (4 different colors)
Toothpicks
Yarn or string
PROCEDURE:
Pass out a set of materials to each student.
Using cereal to represent bases, assign each base a certain color - yellow/thymine, green/adenine, pink/cytosine and blue/guanine.
Pair and connect bases using toothpicks.
Cut straws into one-inch pieces and arrange by alternating color.
Connect the pieces of straw using the yarn or string.
Finally connect the cereal bases to the straw strands.
QUESTIONS:
Which bases pair together?
What is a code?
What do the pieces of cereal represent?
What do the pieces of straws represent?
What makes up the rungs of the ladder?
What makes up the sides of the ladder?
EXTENSION:
Using your individual model demonstrate the replication process.
DO YOU SEE WHAT I SEE?
OBJECTIVE:
Students will understand how to extract DNA from a given cell source.
MATERIALS:
Several plant tissues- broccoli, spinach, and onion
Blender
Warm water
Plastic container
Clear glass
Strainer or filter paper
Rubbing alcohol
Meat tenderizer, any variety
Liquid detergent
PROCEDURE:
Cut up small amount of plant tissue.
Put into blender.
Add warm water and blend until consistency is similar to thick soup.
After obtaining desired consistency, pour mixture through a strainer into a small plastic container.
Add 1/4-cup liquid detergent and 1-tablespoon meat tenderizer. Stir for about 5 minutes.
Empty 1/2 the mixture into a clear glass container.
Hold the container at a slightly tilted angle and slowly pour the alcohol down the side of the glass so that it forms a layer on top of the soap mixture.
Let it stand for about 5 minutes and you will observe white stringy stuff that rises to the top of the container.
Gather some DNA, slowly rotating it on a glass rod and observe it.
QUESTIONS:
What does the blender do?
Why is liquid detergent used in the experiment?
What does the meat tenderizer represent?
How come alcohol is used rather than water to extract the DNA?
Which part of the cell is the DNA located in?
DECISIONS, DECISIONS!!!
OBJECTIVE:
Students will analyze a bioethical scenario and prepare a written presentation that explains their position.
MATERIALS:
Bioethical studies 1 and 2
PROCEDURE:
Assign one of the scenarios.
Students will read and analyze the scenario and will prepare a written presentation demonstrating their knowledge of basic genetics and bioethics.
SCENARIOS:
Research has confirmed that an inherited gene causes Sickle Cell Anemia. Recently Alice found out that her mother carried the gene. Alice’s oldest daughter Jane just got married and is considering starting a family. She needs to know if she is a carrier of the gene and thus needs some medical testing. Unfortunately her husband is unemployed and they lack insurance. Where does Jane go from here?
After the birth of their second child, Frank and Tina were very excited. While Tina was busy one morning the baby fell and broke his arm. After being rushed to the hospital and treated, life seemed to go on normally for the next couple of weeks. During the baby’s routine arm check-up, x-rays revealed that the bones were completely healed. Doctors were so confused by this amazing recovery that they began to perform a series of tests on the child.
After extensive testing the doctors discovered that the baby had a rare gene that gives him the power to heal broken bones at a rate confusing to man. Immediately the doctors get so excited. They approach Frank and Tina with this amazing news and ask their permission to extract some of the baby’s DNA so that the gene can be cloned. News like this travels very fast and reporters and several biotechnology companies bombard Frank and Tina. The companies are offering 5 million dollars for DNA samples. What should Frank and Tina do?
QUESTIONS:
What is the dilemma?
What are the facts?
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What are your views on the issue?
What are arguments for and against?
Who will be affected by the decisions reached?
What ethical problems does the decision seem to raise?