Concept Check Questions

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Concept Check Questions
15.1 Which of Mendels laws relates to the
inheritance of alleles for a single character?
Which law relates to the inheritance of alleles
for two characters in a dihybrid cross? What is
the physical basis of these laws?
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Concept Check Questions
15.1 If the eye-color locus in Drosophila were
located on an autosome, what would be the sex and
phenotype of all the F2 offspring produced by the
crosses in Figure 15.4 (orange book) or Figure
15.3 (green book)?
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Concept Check Questions
15.2 When two genes are located on the same
chromosome, what is the physical basis for the
production of recombinant offspring in a test
cross between a dihybrid parent and a
double-mutant parent?
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Concept Check Questions
15.2 For each type of offspring in Figure 15.5
(orange book) or Figure 15.4 (green book),
explain the relationship between its phenotype
and the alleles contributed by the female parent.
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Concept Check Questions
15.2 Genes A, B, and C are located on the same
chromosome. Test crosses show that the
recombinant frequency between A and B is 28 and
between A and C is 12. Can you determine the
linear order of these genes?
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Concept Check Questions
15.3 A white-eyed female Drosophila is mated
with a red-eyed (wild type) male, the reciprocal
cross of that shown in Figure 15.4 (orange book)
or Figure 15.3 (green book). What phenotypes and
genotypes do you predict for their offspring?
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Concept Check Questions
15.3 Neither Tim nor Rhoda has Duchenne muscular
dystrophy, but their firstborn son does have it.
What is the probability that a second child of
this couple will have the disease?
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Concept Check Questions
15.4 More common than completely polyploid
animals are mosaic polyploids, animals that are
diploid except for patches of polyploid cells.
How might a mosaic tetraploidan animal with some
cells containing four sets of chromosomesarise?
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Concept Check Questions
15.4 About 5 of individuals with Down syndrome
have a chromosomal translocation in which one
copy of chromosome 21 is attached to chromosome
14. How could this translocation in a parents
gonad lead to Down syndrome in a child?
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Concept Check Questions
15.4 Explain how a male cat could have the
tortoise shell phenotype.
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Concept Check Questions
15.5 Gene dosage, the number of active copies of
a gene, is important to proper development.
Identify and describe two processes that help
establish the proper dosage of certain genes.
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Concept Check Questions
15.5 Reciprocal crosses between two primrose
varieties, A and B, produce the following
results A female x B male ? offspring with all
green (nonvariegated) leaves. B female x A male
? offspring with spotted (variegated) leaves.
Explain these results.
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Concept Check Questions
15.5 Mitochondrial genes are critical to the
energy metabolism of cells, but mitochondrial
disorders caused by mutations in these genes are
usually not lethal. Why not?
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Concept Check Questions
16.1 How did bacterial transformation occur in
Griffiths famous experiment?
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Concept Check Questions
16.1 In Hershey and Chases experiment with the
virus T2, what result would you expect if protein
were the genetic material?
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Concept Check Questions
16.1 A fly has the following percentages of
nucleotides in its DNA 27.3 A, 27.6 T, 22.5
G, 22.5 C. How do these numbers demonstrate
Chargaffs rules?
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Concept Check Questions
16.1 How did Watson and Cricks model
demonstrate Chargaffs rules?
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Concept Check Questions
16.2 What role does complementary base pairing
play in the replication of DNA?
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Concept Check Questions
16.2 Identify two major functions of DNA pol III
in DNA replication.
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Concept Check Questions
16.2 Why is DNA pol I necessary to complete
synthesis of a leading strand? Point out in the
overview box in Figure 16.16 (orange book and
green book) where DNA pol I would fuction on the
top leading strand.
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Concept Check Questions
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Concept Check Questions
16.2 How are telomeres important for preserving
eukaryotic genes?