Name: ______________________________________________ Date: ___________________________
Chapter 15 Reading Guide
1.
What is the chromosomal theory of inheritance?
2. List three reasons why the fruit fly is an excellent subject for genetic studies.
3. What are “wild type” flies? How are wild-type alleles symbolized in Morgan’s notation system?
4. Explain why it is easier for a male fruit fly to have white eyes than a female fruit fly.
5. How does the human method of sex determination differ from that of birds and from bees?
6. What is the definition of a sex-linked gene? What are two examples of human disorders located
along the X chromosome?
7. What is a Barr body? In what human cells are they found?
8. What are linked genes? Do they tend to sort independently?
9. What is genetic recombination?
10. What is the difference between a parental type and a recombinant type?
11. By what process do linked genes become unlinked (broken apart onto different chromosomes)?
What stage of meiosis does this process occur?
12. What is a linkage map? How are map units on a linkage map defined?
13. Describe each of the following chromosome abnormalities:
a. Nondisjunction
b. Aneuploidy
c. Monosomy
d. Trisomy
e. Polyploidy
14. There are four errors that alter chromosome structure. Identify each error below.
15. What chromosomal abnormality causes Down’s syndrome? What are three characteristics of
this disorder?
16. For each of the following sex chromosome abnormalities, give the sex of the individual as well as
a description of the symptoms.
a. XXY
b. XXX
c. XO
d. XYY
17. What is genomic imprinting?