Presented by; Mrs. Barr Mrs. Batten Punnett square Presented by; Mrs. Barr Mrs. Batten

Tool used to predict or identify hereditary results Punnett Square Tool used to predict or identify hereditary results

Alleles Each cell has 2 for each trait Can be the same– AA, aa called homozygous Can be different – Aa called heterozygous

Genotype Vs. Phenotype Genotype– the actual genes ---- RR, Rr. rr Phenotype – the way it looks---- Red, Red, white

How to make a punnett Square Decide which letters to use to represent the trait Ie. Trait is flower color we will use the letter R Trait is height we could use the letter T Hair type we could use the letter W

How to make a punnett Square 2. Determine if the parent is heterozygous or homozygous for that trait Homozygous could be RR, or rr Heterozygous would be Rr

How to make a punnett Square 3. Know if they are dominant or recessive Capital letters represent dominant Lower case letters represent recessive

How to make a punnett Square 4. Draw the box

How to make a punnett Square Fill in the letters for each parent R r R r

How to make a punnett Square 6. Fill in the grid R r R r RR Rr rr

Let’s Practice Tall is dominant (T) Mom is heterozygous Dad is heterozygous Lets draw the punnett square for them. TT Tt Tt tt

Ratios Genotypes: TT 25% Tt 50% tt 25% Phenotypes Tall 75% Short 25%