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Moore, Timothy
Moore, Timothy
Instructor: Mrs. Tammy Moore
Class: VHSG Online Biology
14 August 2010
EXPERIMENT 8.3
Sex-linked Genetic Traits
Understanding how sex-linked traits are passed from parents to offspring
Abstract
[What you will put here: Summarize the whole report in one, concise paragraph of about 100-200
words. You cannot write the abstract until after you've completed the report. Because it assumes that
you will speak to your conclusion or what you learned in brief.]
Introduction
[What you will put here: In this introduction, some background is provided for the reader
(sources are noted in the reference section at the end of the report).Typically, the introduction states the
problem to be solved or the experiment to be performed and explains its purpose and significance. It
also provides whatever background theory, previous research, or formulas the reader needs to
understand to perform the experiment (or solve the problem).]
Methods and Observations
Materials

Lab notebook
Background:
Historically, the English and Russian royalty had problems with hemophilia, a disease that inhibits the
blood’s ability to form clots. People with this disease are prone to excessive bleeding. In fact, it is
very possible for hemophiliacs to bleed to death as a result of minor cuts. This devastating disease is a
Moore, Timothy
sex-linked, recessive characteristic. Queen Victoria of England was heterozygous in this trait. Thus,
she carried the recessive allele for hemophilia, but since she had the dominant allele on her other Xchromosome, she did not actually have the disease.
Procedure:
Since this trait is sex-linked, the allele is designated as Xh. The “h” is lower case because it is
recessive. As Queen Victoria was heterozygous, she must have been XHXh. Her husband did not have
hemophilia, so his genotype would have to have been XHY. Using this information, I drew a Punnett
square that would illustrate what their children’s genotype might be. I found that [insert your findings
here.]
Leopold, the son of Queen Victoria and her husband, was a hemophiliac. His genotype was
[insert the genotype of Leopold.]
Hemophilia can also be present in females. I created a Punnett square showing how it is
possible to produce hemophiliac females. [Use whatever genotypes you need for the parents in order to
get a female offspring with hemophilia.]
DATA:
[Include your Punnett squares and findings here.]
Conclusion
My observations [You must explain, analyze, and interpret your results, being especially careful
to explain any errors or problems.]
References
Dr. Jay L Wile and Marilyn F. Durnell
Apologia Exploring Creation with Biology, 2nd edition, copyright 2005 Apologia Educational
Ministries, Inc