Warm Up Use the following terms to label each genotype- homozygous dominant, homozygous recessive, heterozygous, pure, hybrid 1.LL 2.Bb 3.Rr 4.Dd 5.mm 6.What is the difference between a genotype and a phenotype? 7.What is the difference between a dominant trait and a recessive one?

YY yellow

Punnett Squares Pg. ___

Today’s Learning Target  I can use a Punnett Square to determine the probability of having certain offspring.  I can explain why one gene will not have an effect on another gene when being passed on to offspring

Punnett Squares 1. Use a letter to represent alleles. a. Dominant allele = capital letter (B) b. Recessive allele =same letter but lowercase (b)

Punnett Squares 1. Use a letter to represent alleles. a. Dominant allele = capital letter (B) b. Recessive allele =same letter but lowercase (b) 2. Define your alleles B = Black / b = white

Punnett Squares 1. Use a letter to represent alleles. a. Dominant allele = capital letter (B) b. Recessive allele =same letter but lowercase (b) 2. Define your alleles B = black fur / b = white fur 3. Determine the parents’ genotypes

Genotype Symbol Genotype Vocabulary Phenotype BB Bb bb Homozygous (pure) DOMINANT heterozygous hybrid carrier Homozygous (pure) RECESSIVE Black white

Punnett Squares 4. Draw a square and divide into 4 boxes

Punnett Squares 4. Draw a square and divide into 4 boxes 5. Fill in genotypes of parents (1 letter at top of each box) a. Parent #1 on top of box b. Parent #2 on side of box

Punnett Squares 4. Draw a square and divide into 4 boxes 5. Fill in genotypes of parents (1 letter at top of each box) a. Parent #1 on top of box b. Parent #2 on side of box 6.Fill in your boxes by dragging the letters (Two letters per box)

Ex: Black fur is dominant over white fur 1. Letter B 2. B = Blackb = White Use Steps to Make a Punnett Square

Black fur is dominant over white fur 1. B = Blackb = White 2. Define your alleles 2. (dominant allele) (recessive allele) Steps to Make a Punnett Square

Black fur is dominant over white fur 1. B = Blackb = White 3. Cross a homozygous black fur with white fur Parent 1 = BBParent 2 = bb Steps to Make a Punnett Square

Steps to Make a Punnett Square 4. Draw a square and divide into 4 boxes Parent 1 = Parent 2 = BB BB b bb b

Steps to Make a Punnett Square Parent 1 = Parent 2 = BBB B b bb b

Steps to Make a Punnett Square 5. Fill in the genotypes of the parents (1 letter on top of each box) Parent 1 = Parent 2 = BB B B b b b b B B B B bb bb All Black Fur

Steps to Make a Punnett Square 6. Fill in the letters by dragging 2 into each box Parent 1 = Parent 2 = Bb B b B b B b BB Bb bb

B = Black fur b = White fur BB BB b b Bb bb

F = Free f = Attached Ff F f F f FF Ff ff Ff

T = Tall t = Short tt t t T T Tt TT

S = Smooth s = Wrinkled ss ss S s Ss ss Ss ss Ss

S = Smooth s = Wrinkled Ss Ss S s SS Ss ss Ss

T = tall t = short Tt Tt T T TT Tt TT 2:2:0 4:0

T = tall t = short Tt Tt T t TT Tt tt Tt 1:2:1 3:1