1. Making a Pedigree Chart

2. Quick Review Genotype=what genes someone has
Genes are usually represented by a letter, a capital letter for the dominant trait, a small case for the recessive.
Ex. Tongue Rolling is dominant, so we use R to represent the tongue rolling
Inablilty to roll your tongue is recessive so we use r to represent the non-rolling gene
For every trait, you get a gene from each parent

3. Genotypes and Phenotypes
Mom and Dad are Rr-that is their genotype, they can also be described as heterozygous-they have 1 of each gene
What is their PHENOTYPE?
The youngest son has a genotype of rr-he is Homozygous recessive-2 copies of the recessive gene
His phenotype?
tongue rollers Rr Rr
I can’t
Roll my
Tongue! Rr rr Rr Rr
non-roller

4. Some common dominant and recessive traits
Widow’s peak is dominant.
You can be homozygous dominant (WW) or heterozygous (Ww) and you will have widow’s peak
What is your genotype and phenotype if you’re homozygous recessive?
ww, no widow's peak

5. Making a Pedigree Chart
Pedigree charts are made to chart family history and see how traits are passed
What generations are these? P1 F1 F2

6. Symbols Used-write it down!
Shade individuals that have the trait you’re studying
Boys=squares (Lucy always calls Charlie Brown a ‘block head’)
Girls-circles

7. Married-connected at side
Siblings-connected at TOP not at the side (hopefully not siblings AND married)
Oldest child-to the left
Question-if shaded individuals in this pedigree have blue eyes, what is the GENOTYPE of the parents?
both must be Bb