Evaluate whether having sickle-cell disease would be advantageous or disadvantageous to a person living in central Africa.

Construct a family pedigree of two unaffected parents with a child who suffers from cystic fibrosis.

When a couple requests a test for cystic fibrosis, what types of questions might the physician ask before ordering the tests?

Summarize how a scientist might use a karyotype to study genetic disorders.

Solve. A coin is tossed 400 times as part of an experiment and lands showing Heads 221 times. A student concludes that this is not a fair coin. What do you think? Justify your reasoning.

Dina wants to find the directrix of a parabola which has its vertex at the origin and its focus on the horizontal axis. She writes the equation for the directrix in the form y=a. Will this be a correct equation for the directrix?

Human populations in central Africa have a high frequency of sickle-cell anemia, a genetic disorder that occurs in individuals who are homozygous for a particular allele of the hemoglobin gene. Despite strong selection against the homozygous sickle-cell condition, the sickle allele is maintained in relatively high frequencies in human populations that live in areas where malaria was historically common (compare the maps; figure source: Piel et al. 2010. Nat Commun 1: 104). Formulate a hypothesis that explains how this deleterious allele could be maintained in the population, even though individuals who are homozygous for the sickle allele are strongly disadvantaged.

What prevents the two strands of DNA from immediately coming back together after they unzip? A. addition of binding proteins, B. connection of Okazaki fragments, C. parting of leading and lagging strands, D. use of multiple areas of replication.

How could the Northeast be described as an important economic, political, and cultural center?

Identify the blood group that results from each combination of genotypes. The first one has been done for you.

$$\begin{matrix} \text{Possible Genotype Combinations} & \text{Phenotypes}\\ \text{A and A} & \text{A}\\ \text{A and B}\\ \text{A and O}\\ \text{B and B}\\ \text{B and O}\\ \text{O and O}\\ \end{matrix}$$

Analyze the role of each item in inheritance. Give an example of a trait governed by each process.

$$\begin{matrix} \text{} & \text{Role in Inheritance} & \text{Example}\\ \text{Epistasis} & \text{} & \text{}\\ \text{Poiygenic traits} & \text{} & \text{}\\ \text{X-chromosome inactivation} & \text{} & \text{}\\ \text{X-linked traits} & \text{} & \text{}\\ \end{matrix}$$

Phenylketonuria (PKU) is a recessive genetic disorder. If both parents are carriers, what is the probability of this couple having a child with PKU? What is the chance of this couple having two children with PKU?

Explain the type of inheritance associated with Huntington’s disease and achondroplasia.

Why might missing sections of the X or Y chromosome be a bigger problem in males than deletions would be in one of the X chromosomes in females?