1. What do the circles represent?
What do the squares represent?
Why are some shapes dark and others light?
What does a line mean between two shapes?

2. In humans, dark hair (B) is dominant to blond hair.
Dark haired individuals are shaded dark.
Clear shapes are blonde.
1. How many of the children have dark hair?
2. What are the genotypes of the parents?
3. What is the genotype of the sons?
4. What are the two possible genotypes of the daughters?

3. Vocabulary: Autosomal and X-Linked (aka sex-linked)
Autosomal traits on found on any chromosome EXCEPT the X or Y chromosome.
X-Linked traits are found on the X chromosome.

4. Because males only have 1 X chromosome, any trait found on their X WILL BE EXPRESSED
Females have 2 X chromosomes, so a recessive trait will only be expressed if the female has a recessive on BOTH of her X chromosomes.

5. With this in mind, what kind of non-mendelian trait is colorblindness?
The pedigree to the right shows the passing on of colorblindness. What sex can ONLY be carriers of colorblindness?
With this in mind, what kind of non-mendelian trait is colorblindness?
Why does individual IV have colorblindness?
Why do all the daughters in generation II carry the colorblind gene?
Name 2 IV-generation
colorblind males. I II
III IV

6. What do the letters stand for?
Is the trait represented dominant or recessive? How do you know?
Is the trait represented autosomal or x-linked? How do you know?

7. Is the trait represented dominant or recessive?
Is it autosomal or x-linked

8. Is the trait represented dominant or recessive? I II
III
Is the trait represented dominant or recessive?
What is the genotype of P I, # 3 and 4?
Is the trait autosomal or x-linked