Family Trees/pedigrees - Genetics Web Assignment
#1
Follow the directions given. Read. Copy and answer the questions on your own paper. DO NOT DO
ANYTHING ELSE YOU ARE NOT INSTRUCTED TO DO.
1. Click on the icon that lets you use the internet (Internet Explorer or Netscape)
2. Once you have your internet browser on, go to the top of your screen and type
http://library.thinkquest.org/18258/index2.htm
3. Click on “Genetic Analysis” under the Genetics section.
4. Start reading and complete the statements or answer the questions completely.
a. What is a pedigree?
b. Copy the table with the symbols used in a pedigree chart.
5. Click the word “carrier” (next to a small magnifying lens) inside the chart. Now you have
another small screen.
c. Define the word carrier
d. What is the point of pedigrees?
e. What are the two types of pedigrees?
f. When are you studying an autosomal pedigree?
g. Define the word proband
h. Summarize the rules when determining the genotype of a proband.
Sex-linked pedigrees
i. A sex-linked pedigree deals with ____________________________________________.
j. Chromosomes XX define ____________ and XY define _________________.
k. Can female carriers pass their genes to sons (XY) and daughters (XX)?
l. ___________ belong to the heterogametic sex and ___________ to the homogametic sex.
m. Why most of the royal family in Europe has hemophilia?
n. What is hemophilia?
o. If a trait is recessive, when do females express the trait?
p. If the father is normal, and the mother is a carrier, ______ of their sons express the
trait, ______ of the daughters will be carriers and ______ will not.