Build molecular models
Students unfamiliar with basic chemistry should begin by reviewing a periodic table. There are a variety of tables to choose from to download and print out at this site http://www.sciencegeek.net/tables/tables.shtml. Use the table to help students understand the role atomic number and electrons play in simple molecule formation.
Diatomic oxygen, carbon dioxide, water, and methane are great models to begin with. If the classroom does not have access to a molecular model kit, you may allow students to use colored gumdrops (black = carbon, blue = hydrogen, etc.) and toothpicks to assemble these molecules. Another option is to purchase a variety of bolts and nuts. Different style nuts (hex, square, brass, wing nuts, etc.) and different lengths of bolts can be used to model molecules and chemical bonding.
To extend this model, protein manufacture can be done as a construction activity. Students can be provided with a three letter RNA codon that would have a complimentary match (A to U, C to G) to an amino acid. Making up all the codes for the entire protein would be a job for the entire class to engage in. Students could then use the materials to simulate transcription and translation. This would be a useful tactile approach which would help students better grasp the steps of transcription and translation.
A method to simulate this with students in the classroom would be to use children's snap toys with adhesive velcro added to simulate hydrogen bonding. Also, as a demonstration, the teacher could use a spray bottle to simulate condensation during connection of monomers.
Insulin evolution lesson
All animals use insulin, so why pigs (and not another animal source) is an interesting thought question for students to consider. Pig and cow/steer insulin was readily available, as many of these animals are raised for their meat. Have students discuss why neither squirrel, elephant nor starling insulin were chosen. Advanced students can learn about the different insulin forms by going to a protein data bank, such as http://ca.expasy.org/ (
Ex
pert
P
rotein
A
nalysis
Sy
stem) or http://www.ncbi.nlm.nih.gov/Structure/
Direct injection or mounted insulin pump is currently the only way to administer insulin. Have students discover why is this is the case. Students should investigate what happens in the digestive system to proteins that are ingested. Students can then explain why it is difficult to make insulin pill. (Digestion would break down the 51 amino acid polypeptide into the constituent amino acids and then they would need to be reassembled by the ribosome.) Can students think of other ways insulin may be delivered to the blood via the digestive system?
Insulin drug delivery
Insulin is also not a candidate for typical transdermal patch drug delivery as the molecule is so large (even though it is small by protein standards), and sufficient quantities could not be absorbed through the skin. Students could research the types of molecules that are delivered by patch, and compare and contrast these molecules with insulin. Students should describe the features of an insulin transdermal patch. The students should include the necessity of the patch to contact the bloodstream, how the dose would be managed, and how side effects could be managed. Other considerations to consider are cost, effectiveness, and patient comfort. What is the possibility of having an inhalable insulin system? (10) How about subcutaneous implantation, or transplantation of islet cells to the liver? (11)
The Ultimate Lesson
Modern medicine has been amazing in helping diabetics. Our students need to realize that avoiding diabetes is their responsibility. Middle school and high school is the time when our long-term habits are set down.
We need to help our students establish healthy ways of living. Students need to eat a healthy diet and get daily exercise. Frequently students do not recognize the long-term danger that comes from a diet of fast food, chips, and soda. We see much convenience food in schools, so can only assume this food is also eaten regularly outside of school.
The Rudd Center (http://www.yaleruddcenter.org/home.aspx) is focused on improving diet and preventing obesity. The Rudd Center has a blog, and regularly posts articles that deal with adolescents and food. If teachers and students were to visit this blog on regular basis and have discussions in the classroom, it may help begin to overcome the enormous pressures our students face in making healthy food choices.
A Healthy Lifestyle Plan
As many New Haven students are obese, this activity is one that should probably be done outside of the classroom, to reduce possible stigmatization.
As students react very positively to activities that directly involve them, students can calculate their own BMI (Body Mass Index). If students have Internet access, they can go to http://www.nhlbisupport.com/bmi/, if not, this is the formula:
BMI = (Weight in Pounds / (Height in inches) x (Height in inches)) x 703
Values over 25 are reason for concern, and weight loss should begin.
Students can then go to the Internet and calculate how many calories they need to eat in a day. http://www.wvda.org/calcs/
Students should then keep track of many they
really
are ingesting daily over the course of a week. Encourage students to keep a log of the calories they are taking in by reading labels and using online calorie counters.
Back in the classroom, students should be encouraged to reflect on their diet and possibly change their diet based on what they learned from their own personal inventory as well as class discussions about healthy eating. There is a wealth of helpful information at http://www.healthierus.gov/nutrition.html