Pedigree Charts - Biology Worksheets printable pdf download

Pedigree Charts - Biology Worksheets

NAME_________________________________PERIOD_________DATE_____________________

Pedigree Charts

All living things have pedigrees. A pedigree is a diagram that shows the occurrence and appearance

(phenotype) of a particular genetic trait, as it is passed from one generation to the next in a given family.

From this information, along with an understanding of inheritance, genotypes of individuals can often be

determined.

Pedigree 1 traces the dimples trait through three generations of a family. Blackened symbols represent

people with dimples. Circles represent females and squares represent males.

III

The following passage describes the family shown in Pedigree 1.

Although Jane and Joe Smith have dimples, their daughter, Clarissa, does not. Joe’s dad has dimples,

but his mother, and his sister, Grace, do not. Jane’s dad, Mr. Renaldo, her brother, Jorge, and her sister,

Emily, do not have dimples, but her mother does.

1. Write the name of each person below the correct symbol in Pedigree 1.

2. How is marriage symbolized?______________________________________________________

3. How are offspring symbolized? ____________________________________________________

4. What do the Roman numerals mean?_______________________________________________

5. On a separate piece of paper, make a pedigree based on the following passage:

Pedigree 2: Ben, Louise, and Matt have freckles, but their mother, Mrs. Cummins, does not. Mrs.

Giordano, Mrs. Cummins’s sister, has freckles, but her parents, Mr. & Mrs. Lutz, do not. Elizabeth and

Sue Giordano are freckled, but their sister Harriet, like her father, is not freckled.

6. What advantages does a pedigree have over a written passage?

CNICHOLS2006

Original Source: Pedigree Chart Activity by Heidi Tither and Melanie Norton

Pedigree Charts - Biology Worksheets