Name ______________________________________________________________________ Anthropology &215



This set of questions is intended to guide you to an understanding of the basic concepts you will need for the
laboratory.
If you anticipate needing this data for the lab, print two copies.
All laboratory preparation assignments are due at start of lab and so can’t be completed during laboratory. This
will be considered as a form of cheating.
Pre-Lab Study Guide (No points, but intended to guide you to knowing what is expected)
Part I: Questions (Ungraded; may require computer work)
Use the data from the appendices and websites to answer these questions.
1. What is a karyotype and how is it used in genetic counseling?
2. What is a pedigree and how is it used in genetic counseling?
3. What is trisomy and how does it occur?
4. Down’s syndrome is the most commonly recognized type of trisomy. What is one other example of a
form of trisomy and which chromosome is affected?
5. What is the difference between Turner syndrome and Klinefelter syndrome?
6. What is meant by the term “homologous pair”?
7. What is an autosome or “autosomal pair”?
8.
Review Appendix B. Then write up notes on how to distinguish the “4 basic modes”. [Hint: This will
greatly aid you in Part B of this study guide.]
Part II: Complete the series of questions associated with the provided pedigrees. (Graded)
Hint: Use this link as a guide: http://faculty.csupueblo.edu/dan.caprioglio/350/pedrules.html
Situation 1: A couple (labeled as X and Y, respectively) comes to you with the following pedigree,
demonstrating a history of sickle cell anemia in both their families.
1) From this pedigree, is this an autosomal or sex-linked disease? How do you know? (0.5 point)
2) Based on this pedigree, is this trait more likely dominant or recessive? How do you know? (0.5 point)
3) Potential Parents X and Y want to know the probability of producing a child with sickle cell anemia
(prior to their being tested)
a. In order to answer their question you construct one or more Punnett squares (use a separate
page, please). [Hint: If this trait is autosomal, select from these genotypes: AA, AS, SS OR
sex-linked, select from these genotypes: XAXA, XA XS, XS XS (for mother) and XAY & XS Y
(for father)] (1 point)
b. Based on the results of the Punnett square(s), what would you tell them? (0.5 point)
4) X and Y were tested and both X and Y are carriers. What would you advise X and Y in the event they
want to know the probability of producing a child with sickle cell anemia?(0.5 point)
Situation 2: A second couple (labeled as P and Q, respectively) comes to you after they have produced a
son (labeled as R) who is red-green-color-blind. They present the following pedigree:
1) From this pedigree, is this trait an autosomal or sex-linked trait? How do you know? (0.5 point)
2) Based on this pedigree, is this trait more likely dominant or recessive? How do you know? (0.5 point)
3) The couple (P and Q) wants to know the probability of producing another son who is color-blind and
the probability of producing a daughter who is color-blind.
a. In order to answer their question you construct one or more Punnett squares. squares (use a
separate page, please). [Hint: If this trait is autosomal, select from these genotypes: CC, Cc, cc
OR sex-linked, select from these genotypes: XCXC, XC Xc, Xc Xc (for mother) and XCY & Xc
Y (for father)] (1 point)
b. Based on the results of the Punnett square(s), what would you tell them? (0.5 point)
4) Based on the data from the pedigree and the Punnett square(s), why would family members H and P
be normal, but family member K be color-blind? (0.5 point)
5) Family member L came to you concerned about her future offspring, what would you advise? (1
point)
6) Situation 3: Unknown family history
1) From this pedigree, is this trait an autosomal or sex-linked trait? How do you know? (0.5 point)
2) Based on this pedigree, is this trait more likely dominant or recessive? How do you know? (0.5 point)
Situation 4: Unknown family history
1. From this pedigree, is this trait an autosomal or sex-linked trait? How do you know? (0.5 point)
2. Based on this pedigree, is this trait more likely dominant or recessive? How do you know? (0.5 point)