raw a Punnett Square showing the cross of a purple people eater that is heterozygous for horns with a purple people eater that does not have horns.
Please Help! – N am e _ ___ __ __ __ __ __ __ __ __ __ __ __ __ _ Per i o d __ __ __ __ _ R e g e n t s B i o l o g y D ate __ ___ __ __ __ __ __ __ __ __ _ 1 of 2 D ev el op ed by
Name _____________________________ Period _________ Regents Biology Date ______________________ 1 of 2 Developed by Kim B. Foglia • www.ExploreBiology.com • ©2008 GENETICS PRACTICE 1: BASIC GENETICS 1. If a blue-eyed woman had children with a homozygous brown-eyed man, what is the chance of any of their children having blue eyes. Show the Punnett Square. _____________________________________________ 2. If a blue-eyed woman had children with a heterozygous brown-eyed man, what is the chance of any of their children having blue eyes. Show the Punnett Square. _____________________________________________ 3. If 2 heterozygous brown-eyed parents had children, what is the chance of any of their children having blue eyes. Show the Punnett Square. _____________________________________________
Name _____________________________ Regents Biology 2 of 2 Developed by Kim B. Foglia • www.ExploreBiology.com • ©2008 4. In purple people eaters, one-horn is dominant and no horns is recessive. Draw a Punnett Square showing the cross of a purple people eater that is heterozygous for horns with a purple people eater that does not have horns. Summarize the genotypes & phenotypes of the possible offspring. ____________________________________ ____________________________________ ____________________________________ ____________________________________ 5. Sickle cell anemia is a real recessive disease of the blood. It causes your red blood cells to be crescent-shaped instead of round which means they can’t do their job of carrying oxygen in your blood. Since it is a recessive disease that means you need two copies of the sickle cell gene to show the disease. If instead you are a heterozygote — you have one good copy of the gene and one sickle cell copy of the gene — you don’t show the disease. But you are carrying the one bad copy of the gene and can pass it on to your children. Therefore, a heterozygote is also called a “carrier”.