Name:
Date:
Class:
Colorblind Pedigree
11b tracing a genetic characteristic through a given pedigree.
Directions: Assign each person in the pedigree with the appropriate genotypes. Use a different color for
lowercase c to show the recessive allele. Determine which people are carriers and shade half their symbols.
Those that are colorblind are already fully shaded.
P
F1
F2
F3
A
C
B
D
G
E
F
H
I
L
J
M
K
N
O
Colorblind questions
1.
What chromosome do fathers pass to their sons?
X or Y
2.
How many X chromosomes do girls get from their mothers? ____
3.
What will be true about all daughters of colorblind fathers and normal vision mothers (mothers that are not carriers)?
_________________________________________________________________.
4.
Why do boys have a greater chance to be colorblind than girls?
__________________________________________________________________________________________________
__________________________________________________________________________________________________
5.
Why can’t a boy be a carrier of colorblindness?
__________________________________________________________________________________________________
__________________________________________________________________________________________________
6.
Which chromosome carries the colorblindness gene? _________