Thursday, November 18, 2010

Nov. 17, 2010

Scribe Post 11/17/10

Sally Y.

What did we do in class today?

• Went over UP pgs. 63~72

• Pedigree chart

• Homework: Lab #35, UP 92 A-F

• Possibility of a quiz tomorrow or Friday!

Pedigree Chart

What is a pedigree chart?

A pedigree chart is a chart that shows the phenotypes of an organism and its ancestors.

<---------- P1 Generation (Parents)

<---------- F1 Generation (Kids in birth order)

<---------- F2 Generation (Grandkids)

You can identify the phenotypes of each shape by looking at the key!

• every rectangle would be male and every circle would be female

• rectangle filled with only orange, we know that phenotype would be a colorblind male

• rectangle is filled entirely with yellow, it is a male with normal vision

• circle contains only yellow, it is a female with normal vision

• a circle with half orange and half yellow would have normal vision with a recessive gene

Note: If you are unsure of whether or not the gene is homozygous or recessive, leave the second allele blank. DO NOT ASSUME!

Next Scribe: James C


  1. Is a phenotype chart only for sex-linked traits?
    (Comment #1)

  2. Yes I think it is. This is because the female is shaded with 2 colors, indicating that she is a carrier for the recessive gene while the dominant gene is shown.

  3. i think a phenotype chart can be used for sex-linked traits as well as other crosses, because in Lab 35, it used the ability to taste PTC, and i don't think that is a sex-linked trait.

  4. FYI...It is called a pedigree chart. And it can be used for ALL types of traits. You will know if it is a sex-linked trait due to the 1/2 shaded sircles (carrier female). Let me know if you have more questions about this...Mrs. A