Name: _________________________                Date: ________________

Bronze & Gold Activity:   Understanding a polygenic, sex linked trait with a lethal allele.

GenScope file: BronzeGold.gs

When the file opens, you will see a pedigree window set to show color. There are three dragons in it - two males and one female. Jake and Joe are bronze and Jennie is gold.
 

1.       Circle all of the possible combinations of alleles for each of the dragons. (Hint: don't forget to use the Dragon Genome reference sheet.)
 
 

2.      Now use the cross tool  to mate Jake and Jennie.

You will get exactly 16 children. Approximately half will be girls and half will be boys. Circle the letter of all the statements below that are TRUE. Example: If "a. All the girls are the same color as their mother." is true, then circle the letter "a."

a. All the girls are the same color as their mother.
b. None of the boys are the same color as their father.
c. Some of the girls are the same color as their mother and some are not.
d. All of the boys are the same color as their father.
e. None of the girls are the same color as their mother.
f. Some of the boys are the same color as their father and some are not.

3.       After you've circled the true statements, use the scissors tool  to cut out (remove) all of Jake and Jennie's children. (Put the tip of the scissors on the horizontal line joining the parents and click.) Now use the cross tool to mate Jennie with Joe (the male dragon on the right) and circle the TRUE statements below:

a. All the girls are the same color as their mother.
b. None of the boys are the same color as their father.
c. Some of the girls are the same color as their mother and some are not.
d. All of the boys are the same color as their father.
e. None of the girls are the same color as their mother.
f. Some of the boys are the same color as their father and some are not.

What is the main difference between Jake and Jennie's children and Joe and Jennie's children?

Based on your research so far, what do you think Jake, Jennie and Joe's color genes look like?
 

Jake	AA Bb	Aa Bb	AA BB	A- B-	a- B-
Jennie	AA Bb	Aa Bb	AA BB	A- B-	a- B-
Joe	AA Bb	Aa Bb	AA BB	A- B-	a- B-

Call your teacher over and explain your reasoning.