Describe mitosis and meiosis. What are the steps in each, and what is the final outcome? When thinking about Meiosis, how does it confirm Mendel’s ideas about segregation and independent assortment of traits? Describe how genetic information is copied and passed on to future generations during the process of cell division.
2. What is DNA? Where is it located, and what are its main functions? How has DNA been used to compare living species and determine evolutionary relationships?
3. Genetics: Solve the following genetics problem by determining how the following traits would assort. Use D/d for Rh. Remember Rh+ is dominant, and Rh- is recessive. Use A, B and O for blood types. Remember it is a co-dominant system with O as the only recessive allele.
The mother is type AB- and the father is type A+
List all possibilities for each parent’s genotype using what you know from the information given so far (assuming you have only read (a) above.
Now assume the father is heterozygous for both traits. What are the genotypes you will use for each parent?
Create a double square (dihybrid cross) to assort these two traits. Show your work.
What are the possible genotypes for each child? Provide a percentage (or a fraction) for each possible genotype.
What are the possible phenotypes for each child? Provide a percentage (or a fraction) for each phenotype.
What are the chances of having a child that is heterozygous for both traits? Provide a percentage and explain your answer.
Is there any possibility that a child will be born to these parents that will show the recessive phenotype(s) for both traits? Explain: Why or why not?
Background: the alleles that control for sickle cell anemia are co-dominant, meaning that if both alleles are present, both phenotypes are expressed. Sickle cell anemia is a condition that is fatal in the homozygous condition (SS). Normal hemoglobin in the blood is (AA). If a person is (AS), this means that they will not die from sickle cell, but may experience some mild symptoms. An advantage of being heterozygous (AS) is that carriers of the (S) allele will have some immunity to malaria, whereas those with (AA) are more likely to suffer and possibly die from this mosquito-born illness.
In your population there are 200 individuals that colonize a new planet. Out of those 200, 50 people in that population are heterozygous for sickle cell anemia.
How many total alleles in the population for this trait?
Determine the percentage of alleles in the population that are S.
Determine the percentage of alleles that are A.
Use the formula to predict the frequency of sickle cell anemia in the next generation. Use the A allele for P and the S allele for q.
How many newborns will likely die from sickle cell anemia in the colony?
How many people will be heterozygous?
How many homozygous for the A allele?
What factors (if any) do these predictions depend on?