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Bellwork: 12/1/15 Match the following terms to their examples
Homozygous dominant Heterozygous Dominant Recessive Phenotype Blue eyes Aa BB A a Have your alien page out for me to collect
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Warm Up 12/7 Title: Dihybrid Crosses Page: 48 Date: 12-7-16
Essential Question: How can I find the probability of a child inheriting more than one trait?
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Answer this question in your notebook (48.1)
Suppose that black hair (B) is dominant over blonde hair (b) and brown eyes (E) are dominant over blue eyes (e). The father has black hair (heterozygous) and brown eyes (heterozygous) and the mother has blonde hair and blue eyes. Genotype of father BbEe Genotype of mother - bbee What are the chances you end up with a Blonde hair, blue eyed, offspring??
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Announcements 10 9 11 13 14 8 12 7 2 1 End 3 4 6 5 15 16 26 25 27 28 30 29 17 24 19 18 23 20 21 22 Cat Half Sheet- 70 today tomorrow 50 Monohybrid cross practice- 50 today tomorrow 0 To make up your quiz, go see a biology teacher in the tutorial lab today after school.
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Test Day=Friday
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What traits do you see pictured below?
Fur color Dihybrid Cross: a cross that shows the possible offspring for two traits Fur length
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What’s the phenotypic ratio?
9:3:3:1
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Dihybrid Cross: a cross that shows the possible offspring for two traits
Fur Color: B: Black b:WhiteCoat Texture: R: Rough r: Smooth Heterozygous x Heterozygous Their genotypes will be: BbRr x BbRr
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Dihybrid Crosses: a cross that shows the possible offspring for two traits
BBRR BbRR BbRr BBRr BBrr Bbrr bbRR bbRr bbrr BbRr x BbRr Fur Color: B: Black b: White Coat Texture: R: Rough r: Smooth
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How many of the offspring would have a black, rough coat?
How many of the offspring would have a black, smooth coat? How many of the offspring would have a white, rough coat? How many of the offspring would have a white, smooth coat? BR bR br Br BBRR BbRR BbRr BBRr BBrr Bbrr bbRR bbRr bbrr Fur Color: B: Black b: White Coat Texture: R: Rough r: Smooth
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Phenotypic Ratio= 9:3:3:1 BR bR br Br
BBRR BbRR BbRr BBRr BBrr Bbrr bbRR bbRr bbrr How many of the offspring would have black, rough coat? How many of the offspring would have a black, smooth coat? How many of the offspring would have a white, rough coat? How many of the offspring would have a white, smooth coat? Phenotypic Ratio= 9:3:3:1 Fur Color: B: Black b: White Coat Texture: R: Rough r: Smooth
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Fractions Method BbRr x BbRr Bb Bb Rr Rr
Step 1: Split the traits for mom and dad MOM DAD BbRr x BbRr Bb Bb Rr Rr
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Step 2: Create 2 punnett squares for the traits
DAD DAD B b R r B BB Bb R RR Rr b Bb r Rr rr bb MOM MOM Step 3: Fill in the punnett squares
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Step 4: Solve problems by multiplying fractions
DAD Fur Color: B: Black b: White DAD B b R r B BB Bb R RR Rr Coat Texture: R: Rough r: Smooth b Bb rr bb Rr r MOM MOM How many of the offspring would have a black, rough coat? 3 3 9 X = 4 4 16
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Step 4: Solve problems by multiplying fractions
DAD Fur Color: B: Black b: White DAD B b R r B BB Bb R RR Rr Coat Texture: R: Rough r: Smooth b Bb rr bb Rr r MOM MOM How many of the offspring would have a black, smooth coat? 3 1 3 X = 4 4 16
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Step 4: Solve problems by multiplying fractions
DAD Fur Color: B: Black b: White DAD B b R r B BB Bb R RR Rr Coat Texture: R: Rough r: Smooth b Bb rr bb Rr r MOM MOM How many of the offspring would have a white, rough coat? 1 3 3 X = 4 4 16
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Step 4: Solve problems by multiplying fractions
DAD Fur Color: B: Black b: White DAD B b R r B BB Bb R RR Rr Coat Texture: R: Rough r: Smooth b Bb rr bb Rr r MOM MOM How many of the offspring would have a white, smooth coat? 1 1 1 X = 4 4 16
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Hybrid= Heterozygous Purebred= Homozygous
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1. *Hybrid* 2. *Purebred* What is the probability that the baby Reebop will have 2 antennae and 3 body segments?
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A a B b A AA Aa b Bb bb AA Aa A b Bb bb 4 2 8 = X 4 4 16
What is the probability that the baby Reebop will have 2 antennae and 3 body segments? 1. *Hybrid* 2.*Purebred* A a B b A AA Aa b Bb bb AA Aa A b Bb bb 4 2 8 = X 4 4 16
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Genotype / phenotype code
1. *Hybrid* 2. Hybrid eyes Characteristic Genotype / phenotype code eyes EE = 2 eyes Ee = 2 eyes ee = one eye humps HH = 1 hump Hh = 1 hump hh = 3 humps What is the probability that the baby Reebop will have 2 eyes and 3 humps?
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Genotype / phenotype code
Characteristic Genotype / phenotype code eyes EE = 2 eyes Ee = 2 eyes ee = one eye humps HH = 1 hump Hh = 1 hump hh = 3 humps What is the probability that the baby Reebop will have 2 eyes and 3 humps? 1. *Hybrid* 2.hybrid eyes E e H h E EE Ee h Hh hh Ee ee e h Hh hh 3 2 6 = X 4 4 16
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In pea plants, yellow seeds (Y) are dominant over green seeds (y), and rounded peas (R) are dominant over wrinkled peas (r). Cross a plant that is heterozygous for both traits with a plant that is homozygous recessive for both traits. Genotypes: YyRr and yyrr What is the probability that the plant will be yellow and wrinkled?
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Y y R r y Yy yy r Rr rr y Yy Rr rr yy r 2 2 4 X = 4 4 16
How many of the offspring would have a yellow, wrinkled seed? 2 2 4 X = 4 OR ¼ 4 16
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What are the traits? What’s dominant/recessive?
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Work on your Dihybrid practice for the rest of class
Work on your Dihybrid practice for the rest of class. We’ll finish tomorrow
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Trait Dominant Gene Recessive Gene Body size Small (S) Large (s) Snow Color White (W) Blue (w) Feet Snow feet absent (F) Snow feet present (f) Nose Style Long (L) Stubby (l) Use the chart to identify the genotype of the following traits: Heterozygous long nose, large body: _________ Hybrid small body, homozygous white snow body: _________ Snow feet present, stubby nose: ____________ Ll ss Ss WW ff ll
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GREEN= Frosty RED= Frosty’s Hunny
Olaf’s best friend, Frosty the (large) Snowman was bragging that he’d found the most adorable snow lady to marry. Frosty loves his (hybrid) small lady’s cute snow feet and wants Olaf to figure out the chances that Frosty can hear the pitter patter of little snow feet running through the forest, even though Frosty doesn’t have any feet of his own (Ff). GREEN= Frosty RED= Frosty’s Hunny
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Identify the genotypes: 4
Identify the genotypes: 4. Frosty: large body, no feet: ____________________ 5. Frosty’s fiancée: small body, feet: __________________ 6. Frosty: long nose (hybrid), white body (hybrid) _______________________ 7. fiancé: long nose (heterozygous), white body (heterozygous) ______________________ 8. What is the probability that Frosty and his fiancé will have a large baby with snow feet? (Hint: Remember to multiply your fractions) ss Ff Ss ff Ll Ww Ll Ww
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