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Problem A.1a
Match each statement (a–e) with the best answer from the following list: consultand, 50%, prior probability, 66.7%, obligate carrier, 100%.
The Mendelian risk that a person is a heterozygous carrier of a recessive condition
Problem A.1b
Match each statement (a–e) with the best answer from the following list: consultand, 50%, prior probability, 66.7%, obligate carrier, 100%.
A person who on the basis of family history must be a heterozygous carrier of a recessive mutant allele
Problem A.1c
Match each statement (a–e) with the best answer from the following list: consultand, 50%, prior probability, 66.7%, obligate carrier, 100%.
The probability that the healthy brother of a woman with an autosomal recessive condition is a heterozygous carrier
Problem A.1d
Match each statement (a–e) with the best answer from the following list: consultand, 50%, prior probability, 66.7%, obligate carrier, 100%.
The person receiving genetic counseling
Problem A.1e
Match each statement (a–e) with the best answer from the following list: consultand, 50%, prior probability, 66.7%, obligate carrier, 100%.
The probability that the son of a woman with an autosomal recessive condition is a heterozygous carrier
Problem A.3
A couple comes into your genetic counseling practice with a question about the chance a future child of theirs might have a genetic disease. Three or four men in the woman's family, including her father, had a condition that might be genetic. Although her father is still alive, she has had little contact with him for much of her life and cannot describe or name the condition. Her partner is a healthy man whose family has no history indicating the presence of a genetic condition. To provide more information about this possible genetic condition for the couple, what is the first step you recommend?
Problem A.2a
Go online to the Online Mendelian Inheritance of Man (OMIM) website. Look up the following genetic conditions and answer the questions posed about them.
Look up Tay–Sachs disease (TSD), OMIM number 272800, and give the name and abbreviation of the affected gene and the chromosome location of the gene.
Problem A.2b
Go online to the Online Mendelian Inheritance of Man (OMIM) website. Look up the following genetic conditions and answer the questions posed about them.
Go to the 'Population Genetics' section discussing the TSD gene. In a few sentences, summarize the human population in which TSD is most frequently found and give the approximate frequency of heterozygous carriers for the TSD mutation in North American Jews.
Problem A.2c
Go online to the Online Mendelian Inheritance of Man (OMIM) website. Look up the following genetic conditions and answer the questions posed about them.
Look up cystic fibrosis (CF), OMIM 602421, and give the gene name and abbreviation and the chromosome location of the gene.
Problem A.2d
Go online to the Online Mendelian Inheritance of Man (OMIM) website. Look up the following genetic conditions and answer the questions posed about them.
Go to the 'Molecular Genetics' section and describe the most common mutation of the CF gene.
Problem 1a
For bacteria that are F⁺, Hfr, F', and F⁻ perform or answer the following.
Describe the state of the F factor.
Problem 1b
For bacteria that are F⁺, Hfr, F', and F⁻ perform or answer the following.
Which of these cells are donors? Which is the recipient?
Problem 1c
For bacteria that are F⁺, Hfr, F', and F⁻ perform or answer the following.
Which of these donors can convert exconjugants to a donor state?
Problem 1d
For bacteria that are F⁺, Hfr, F', and F⁻, perform or answer the following.
Which of these donors can transfer a donor gene to exconjugants?
Problem 1e
For bacteria that are F⁺, Hfr, F', and F⁻, perform or answer the following.
Describe the results of conjugation (i.e., changes in the recipient and the exconjugant) that allow detection of the state of the F factor in a donor strain.
Problem 1f
For bacteria that are F⁺, Hfr, F', and F⁻, perform or answer the following.
Describe a "partial diploid" and how it originates.
Problem 2
The flow diagram identifies relationships between bacterial strains in various F factor states. For each of the four arrows in the diagram, provide a description of the events involved in the transition.
Problem 3
Conjugation between an Hfr cell and an F⁻ cell does not usually result in conversion of exconjugants to the donor state. Occasionally, however, the result of this conjugation is two Hfr cells. Explain how this occurs.
- Bacteria transfer genes by conjugation, transduction, and transformation. Compare and contrast these mechanisms. In your answer, identify which if any processes involve homologous recombination and which if any do not.
Problem 4
Problem 5a
Explain the importance of the following features in conjugating donor bacteria:
the origin of transfer
Problem 5b
Explain the importance of the following features in conjugating donor bacteria:
the conjugation pilus
Problem 5c
Explain the importance of the following features in conjugating donor bacteria:
homologous recombination
Problem 5d
Explain the importance of the following features in conjugating donor bacteria:
the relaxosome
Problem 5e
Explain the importance of the following features in conjugating donor bacteria:
relaxase
Problem 5f
Explain the importance of the following features in conjugating donor bacteria:
T strand DNA
Problem 5g
Explain the importance of the following features in conjugating donor bacteria:
pilin protein
Problem 6
Describe the difference between the bacteriophage lytic cycle and lysogenic cycle.
Problem 7
Describe what is meant by the term site-specific recombination as used in identifying the processes that lead to the integration of temperate bacteriophages into host bacterial chromosomes during lysogeny or to the formation of specialized transducing phage.
Problem 8
What is a prophage, and how is a prophage formed?
Problem 9
How is the frequency of cotransduction related to the relative positions of genes on a bacterial chromosome? Draw a map of three genes and describe the expected relationship of cotransduction frequencies to the map.
