Dragon Genetics

thingiverse

This project is a lesson in Mendelian genetics for an 8th-grade class, based on the original concept by Dr. Pamela Esprivalo Harrell published in the January 1997 issue of Science Scope. The activity uses pieces of paper to create a dragon and covers genotypes, phenotypes, dominant and recessive alleles. The project is divided into two parts: Dragon Genetics and Dragon Breeding. In part one, students learn about Mendelian genetics, including genotypes, phenotypes, and alleles. They draw Punnet squares in the second part. In the activity, incomplete dominance is introduced through dragon body color. Students can easily adapt the activity to use just 2 body colors or eliminate it altogether by printing all models in the same color. The dragon models were inspired by http://www.thingiverse.com/thing:5236 and created with help from an art teacher. In this activity, the model is copied, mirrored, and flipped to make the reverse side. The two pieces are then glued together. The standards for the activity include: * NGSS * Objective: + Each trait is determined by two factors called genes. + You inherit one gene for each trait from each parent. + The different forms of a gene are called alleles. + Some alleles are dominant, some are recessive. A dominant allele overpowers a recessive one if both are present. + The combination of genes is called a genotype. + Genotypes can be homozygous/purebred (both alleles the same) or heterozygous/hybrid (alleles are different). + The observable trait caused by the combination of alleles is called a Phenotype. Preparation: This project is intended to be part of a unit on genetics and heredity. Before beginning the activity, download the Dragon Genetics PDF and make copies for the students or copy it from Google Docs: https://docs.google.com/document/d/1gJFkw7j4BTVxqDdKa7M6ZXxIHoV5WMvjzglo4uDB8pM/edit?usp=sharing. Download and print the Dragon Chromosomes PDF or copy it from Google Docs: https://docs.google.com/document/d/1NttirXMCrUwSjEeomqXPG_EI-cnPNvE5Bpp3_FTaq44/edit?usp=sharing. I print the male chromosomes on blue paper and the female chromosomes on pink paper. Each student will need a male and female set of chromosomes, which can be put inside plastic Easter eggs. You can get the eggs dirt cheap after Easter. Steps: Copy the genes from the female and male chromosomes onto your workshop. Dominant alleles should be written before recessive ones. Use the key to determine the phenotype for each trait. Make up a name for your dragon. Login to Tinkercad and open the Dragon Genetics Construction Kit or download the pieces you need from Thingiverse. Build your dragon according to math your phenotypes, making sure all the pieces are solidly connected (rotate the model and look carefully to be sure). Delete all extra pieces. Duplicate your dragon model, mirror it through the X-Y plane, then flip 180 degrees to make the reverse side. Download and print your dragon model in the correct color plastic. Glue the pieces together. Results: This project was completed successfully with two 8th-grade science classes. Print the models at 50% or 75% for cute little baby dragons. Dragon Breeding Objective: This is a follow-up to the Dragon Genetics activity that includes selective breeding and drawing Punnet Squares. Preparation: You need a group of male and female dragons for the students to choose from. I used the dragon models the students created in the Dragon Genetics activity for the gene pool. Male and female dragons were put on separate tables with a list of their genotypes. In a pinch, you could just have the genotypes of the dragons available without the models. Download and print the Dragon Breeding PDF or copy it from Google Docs: https://docs.google.com/document/d/1kTZwuXVlfcqvkui6_cIJQmMW4YiuKyi5xA6jdrJWPts/edit?usp=sharing. Steps: Decide what trait(s) you'd like in your baby dragon. Make a plan for how you will choose the mother and father dragon that will have the best chance of creating a baby with the trait(s) you want. Choose a mother and father dragon, copy their genotypes onto your worksheet. Use coin flips to determine which gene you inherit from each parent for each trait. Use the key to determine the phenotypes of your baby dragon. Make up a name for your dragon. Login to Tinkercad and open the Dragon Genetics Construction Kit or download the pieces you need from Thingiverse. Build your dragon according to math your phenotypes, making sure all the pieces are solidly connected (rotate the model and look carefully to be sure). Delete all extra pieces. Duplicate your dragon model, mirror it through the X-Y plane, then flip 180 degrees to make the reverse side. Download and print your dragon model in the correct color plastic. Glue the pieces together. Results: This project was completed successfully with two 8th-grade science classes. Print the models at 50% or 75% for cute little baby dragons.