Genetics with a Smile Genetics with a Smile

Genetics with a Smile

Genetics with a Smile Key Question: How do genes determine a trait? What happens to the parent’s gene that doesn’t show? Initial thoughts:

Evidence: Poppy & Skye Generation 1: Skye (blue tail) Poppy (orange tail) TT tt Homozygous = 2 copies of the same gene Blue, or T, is dominant over Orange, or little t. Little t is recessive. What is Skye’s phenotype? What is Skye’s genotype?

Generation 2 (Skye & Poppy’s Offspring) Ocean Tt Lucy Tt Heterozygous = 2 different genes What is their genotype? What is their phenotype?

Evidence 2: Smiley Face • Part A: Smiley Face Traits • Obtain two coins from your teacher. Mark one coin with a “F” and the other with a “M” to represent each of the parents. The parents are heterozygous for all the Smiley Face traits.

Evidence 2: Smiley Face • Part A: Smiley Face Traits • Flip the coins for parent for each trait. • If the coin lands with heads up, it represents a dominant allele. • A coin that lands tails up indicates a recessive allele. • Record the result for each person by circling the correct letter. • Use the results and the Smiley Face Traits page to determine the genotype and phenotype for each trait.

Create Your Smiley Face • Use the Smiley Face Traits chart and your results from Part A to create a sketch of your smiley face in the box. • Once you have completed the sketch, use the drawing tools in Microsoft Word to create your smiley face! • You can print it out later, or email it to me.

Summary Minimum of 4 sentences – What did you think before about how genes determine a trait (look back at your initial thoughts) – What did you learn about how genes determine a trait? – What evidence do you have that you learned this? – Further Thoughts

Reflection What are the traits you have received from your mom? What are the traits you have received from your dad? Do you think those traits are more dominant or recessive?

Big Idea