Genetics in Offspring

1) Working with a partner, you will determine the genotype of the your 'offspring' by flipping coins. {Actual coins, use of an app, or ask Siri} "Mom" flips one penny to choose an allele for her egg and "Dad" flips the other to choose an allele for his sperm.

  • Note that the gender of the baby is a special case and is determined by dad alone. Boys are XY and girls are XX. Mom can give only an X but dad can give either an X (heads) or a Y (tails).

2) Record the alleles which resulted from the coin flips, and put "sperm and egg" together. Write down baby's genotype for each trait on your own paper. Heads represents Dominant allele and tails represents recessive allele.

  • Use the same technique with co-dominant traits: Heads = 1 Tails = 2.

  • Hair color and Eye color are multiple alleles, so you will have to flip four times with Heads being dominant trait and tails being recessive traits.

      • Example flip Heads, Tails, Heads, Heads = Dark Brown Hair

3) Record the offspring's phenotype on your paper. Note: Dominant alleles are written with an uppercase letter and recessive alleles are written as lowercase letters.

  • Dominant alleles mask the expression of recessive ones. Co-dominant alleles are written as uppercase letters with a subscript. (D1D1 = Dark)

  • Co-dominant alleles (like skin color) result in a phenotype that is blended.

4) Repeat steps 1, 2, and 3 for all traits and then draw, color, and name your creation. Remember that you are drawing your potential offspring. Use back side of paper to get basic positioning and proportions correct.

5) Compare your final drawing to others