DISCUSSION QUESTIONS
- Compare your baby to his/her parents. Does s/he have the same genotype? Does s/he have the same phenotype? Why or why not? Each parent only contributes one of their two chromosomes to their offspring and those chromosomes combine to form different combinations than what each parent started with.
- Compare your prediction to the actual baby’s genotype or phenotype. Chances are you were not 100% accurate. Explain why or why not. There are many ways the genes can combine to form offspring with different characteristics.
- The picture at the top of the lab is an older sibling of your baby! Which two laws from Mendel support the idea that siblings are not identical even though they come from the same parent? Law of Independent Assortment, Law of Segregation
- Which traits in Reebops appear to “blend” and show incomplete dominance? Humps, Legs, Nose, Antennae (the traits with 3 options for outcomes)
- Which traits in Reebops appear to show complete dominance? Body segments, Tail, Eye Number, Blindness (the traits with only two outcomes)
- The parents in this cross actually have 12 other Reebop babies. Of them, 6 males and 1 female child is blind. Why does a difference exist in the number of females with blindness than without blindness? Hint: Use a Punnett Square to support your argument. When you do ALL the possible parent combinations for sight/blindness and gender, there is a higher overall likelihood that boys will be born blind than girls (depending on what their parent’s blindness genes were).
XBXB + XBY = 2XBXB:2XBY; all babies sighted
XBXb + XBY = XBXB:XBXb:XBY:XbY; all girls sighted, 50% boys blind
XBXb + XbY = XBXb:XbXb:XBY:XbY; all babies 50% blind
XbXb + XBY = 2XBXb:2XbY; all girls sighted, all boys blind
XbXb + XbY = 2XbXb:2XbY; all babies blind