sc235 unit nine prof. christine s. snyder, ph.d [email protected]
TRANSCRIPT
This week’s Discussion• Read up on cloning, starting with the Oak Ridge National Laboratory's
excellent Cloning Fact Sheet. Then respond to these big issues throughout the week, both in your own postings and in responses to your classmates' postings.
• * What are the risks and benefits of cloning?• * What are some potential uses for cloning?• * Could you envision using cloning technology in your own life? If so, how?• * What are some of the ethical problems with cloning?• * How do you feel about cloning animals? What about humans?• * Should cloning be regulated? If so, by whom?
Beak color is an autosomal trait in chickens. Red beaks are dominant over white beaks. Claude is a chicken that has a red beak and has a genotype of Rr. If this chicken mates with a white-beaked chicken named Filette, what will the baby chickens look like? Be sure to indicate the babies' genotypes and phenotypes.
Punnett squares are used by geneticists to determine the probability of different offspring genotypes. In the one shown below, what letter(s) belong in the lower right box?
QuickTime™ and a decompressor
are needed to see this picture.a
a
A a
A person who is homozygous dominant for the T allele decides to have children with a person who is homozygous recessive. What will their children be like? Again, include the children's genotypes and phenotypes.
If a woman is homozygous normal and her husband is heterozygous for a genetically inherited recessive disease and they decide to become parents, what is the probability that they will have a healthy child?
If two parents are heterozygous for a genetically inherited dominant trait, what is the probability that they will have a child together who has this trait in his or her phenotype?
If two parents are homozygous for a genetically inherited recessive trait, what is the probability that they will have a child who does not have this trait in his or her phenotype?
Codominant alleles: The human ABO markersHuman blood type is determined by codominant alleles. There are three different alleles, known as IA, IB, and i. The IA and IB alleles are codominant, and the i allele is recessive.
The possible human phenotypes for blood group are type A, type B, type AB, and type O. Type A and B individuals can be either homozygous (IAIA or IBIB, respectively), or heterozygous (IAi or IBi, respectively).
A woman with type A blood and a man with type B blood could potentially have offspring with which of the following blood types?
Questions?
Image credit: Microsoft Clip Art
References
Slides were McGraw Hill , Biology 9th edition