Pencil Preparation Duplicate the Genetic Profile Worksheet and distribute to students. The Popsicle sticks or tongue depressors will represent chromosomes . Use a different color marker or crayon for each type of gene, and use thick lines for dominant alleles and thin lines for recessive alleles. Vary the frequency of dominant and recessive alleles for each gene. Be sure to put the lines for each gene at the same location on each stick to help convey the idea that they represent alleles on a chromosome.
Instructions Divide the class into pairs.
Give each student two sticks and the Handouts. Explain that each pair of sticks represents the possible genetic material that can be donated from one parent, and that each line on the stick represents a different gene from that parent. Have each pair of students decide which pair of sticks represents the mother's genetic material and which represents the father's genetic material. Ask them to locate the PKU alleles on their trait sticks. Ask them to use the colored pencils to indicate the phenotype of each parent on the form.