University of Pittsburgh at BradfordScience in MotionBiology Lab
Dragon Genetics – TEACHER NOTES
Activity 1: “I’m all Keyed Up” – Students learn to understand a key representing the genetic traits of the dragons.
Activity 2: “Would Someone Please Take Charge?” – Based on the key, students fill in the missing symbols (genotypes) or descriptions of physical appearance (phenotypes) in the table. The students will need to refer to the key from Worksheet #1.
Activity 3: “Do Your Ears Hang Low?” – Students determine whether they are dominant or recessive for various human phenotypes, such as tongue rolling, hitchhikers’ thumb, etc. Students may also determine possible genotypes to match their phenotype for each trait. NOTE: The letters representing the alleles for each trait are noted in parentheses at the end of each statement (upper case for dominant and lower case for recessive). These letters were arbitrarily chosen. You may want to explain to students that any letter can be used to represent the symbol for an allele.
Activity 4: “Enter the Dragon” – Students are shown two dragon “chromosomes”: one from the mother dragon and one from the father dragon. Using the key from Activity 1 as a reference, students determine the genotypes and phenotypes that are coded for on these chromosomes. The dragon body parts on the transparencies can be used to illustrate the combinations of phenotypes that can exist in the baby dragon. The color poster illustrates the 16 possible baby dragons that result from the given combinations of the 16 egg and 16 sperm. Since there are 13 traits with two possibilities for each, it is possible to make 8,192 (that is 213) different dragons.
Activity 5: “Dragon Genetics” – Students work in pairs. One student in each pair gets an “egg” filled with four dragon chromosomes; the other student in the pair gets a “sperm” filled with 4 dragon chromosomes. Students determine the genotypes and phenotypes of their dragon “offspring”. They then construct and color this dragon, using the appropriate pieces from the blackline dragon worksheet.
Each activity builds on the previous one. Generally, each activity introduces a new concept. After the activity, the concept is discussed and reinforced by the teacher. You may prefer to present the related lesson before students do the activity. Each activity can usually be completed in a single class period. If necessary, some of the activities can be completed as homework. Activity 5 may take more than one class period to complete.
Poster Key: The following key shows the position of each baby dragon, by number, on the poster. The dragon in the top left corner is baby dragon #1; the dragon in the bottom right corner is baby dragon #16. You can refer to the poster to see if each group chose the proper phenotype for each of the 13 specified dragon traits. The students should not be allowed to examine the poster until they have completed their baby dragons.
1 / 2 / 3 / 45 / 6 / 7 / 8
9 / 10 / 11 / 12
13 / 14 / 15 / 16
Extension Activity: As a possible extension for more advanced classes, the students may pair their baby dragons randomly with other groups to create an F2 generation. With this activity, the teacher can incorporate Punnett squares and Mendelian ratios so students can determine the probability of genotypes and phenotypes for F2 dragons. To establish the baby dragon’s genotype, dice can be rolled to ensure the genotype is chosen at random, and simulate the probability of each genotype/phenotype.
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Teacher Notes adapted from Science Kit® & Boreal® Laboratories “Dragon Genetics”