Question

name:punnett square practice 1 version 2instructions: use the information provided to complete the punnett square and calculate the genotypic and phenotypic ratios.1. hornless (h) in cattle is dominant over horned (h). a homozygous hornless bull is mated with a homozygous horned cow. what will be the genotype and phenotype of the offspring?genotypic ratio ____:__:__phenotypic ratio __:__chances of having a hornless cow ________2. in tomatoes, red fruit (r) is dominant over yellow fruit (r). a plant that is homozygous for red fruit is crossed with a plant that has yellow fruit.what will be the genotype and phenotype of the offspring?genotypic ratio __:__:__phenotypic ratio __:__chances of having red tomatoes ________3. brown eyes in humans are dominant to blue eyes. a brown-eyed man, whose mother was blue-eyed, marries a brown-eyed woman whose father had blue eyes.genotypic ratio __:__:__phenotypic ratio __:__chances of having blue eye offspring? ________4. in humans, free-earlobes are dominant to attached lobes. two parents that are both heterozygous free are expecting a child.genotypic ratio __:__:__phenotypic ratio __:__chances of having offspring with free-earlobes? __5. in mice, red eyes are dominant over black eyes. show a cross between two black-eyed mice.genotypic ratio __:__:__phenotypic ratio __:__chances of red eyes mice? __________

Explanation:

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Problem 1

Step1: Identify parent genotypes

Homozygous hornless bull: $HH$; Homozygous horned cow: $hh$

Step2: Set up Punnett Square

	$H$	$H$
$h$	$Hh$	$Hh$

Step3: Calculate ratios

Genotypic ratio: $0:4:0$ (HH:Hh:hh)
Phenotypic ratio: $4:0$ (hornless:horned)
Chance of hornless cow: $\frac{4}{4}=100\%$

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Problem 2

Step1: Identify parent genotypes

Homozygous red fruit plant: $RR$; Yellow fruit plant: $rr$

Step2: Set up Punnett Square

	$R$	$R$
$r$	$Rr$	$Rr$

Step3: Calculate ratios

Genotypic ratio: $0:4:0$ (RR:Rr:rr)
Phenotypic ratio: $4:0$ (red:yellow)
Chance of red tomatoes: $\frac{4}{4}=100\%$

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Problem 3

Step1: Identify parent genotypes

Brown-eyed man (mother blue-eyed $hh$): $Hh$; Brown-eyed woman (father blue-eyed $hh$): $Hh$

Step2: Set up Punnett Square

	$H$	$h$
$h$	$Hh$	$hh$

Step3: Calculate ratios

Genotypic ratio: $1:2:1$ (HH:Hh:hh)
Phenotypic ratio: $3:1$ (brown-eyed:blue-eyed)
Chance of blue-eyed offspring: $\frac{1}{4}=25\%$

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Problem 4

Step1: Identify parent genotypes

Both heterozygous free earlobes: $Ee$

Step2: Set up Punnett Square

	$E$	$e$
$e$	$Ee$	$ee$

Step3: Calculate ratios

Genotypic ratio: $1:2:1$ (EE:Ee:ee)
Phenotypic ratio: $3:1$ (free:attached)
Chance of free earlobes: $\frac{3}{4}=75\%$

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Problem 5

Step1: Identify parent genotypes

Black-eyed mice (recessive): $bb$

Step2: Set up Punnett Square

	$b$	$b$
$b$	$bb$	$bb$

Step3: Calculate ratios

Genotypic ratio: $0:0:4$ (BB:Bb:bb)
Phenotypic ratio: $0:4$ (red-eyed:black-eyed)
Chance of red-eyed mice: $\frac{0}{4}=0\%$

Answer:

1. Genotypic ratio: $\boldsymbol{0:4:0}$ (HH:Hh:hh)

Phenotypic ratio: $\boldsymbol{4:0}$ (hornless:horned)
Chances of having a hornless cow: $\boldsymbol{100\%}$

1. Genotypic ratio: $\boldsymbol{0:4:0}$ (RR:Rr:rr)

Phenotypic ratio: $\boldsymbol{4:0}$ (red:yellow)
Chances of having red tomatoes: $\boldsymbol{100\%}$

1. Genotypic ratio: $\boldsymbol{1:2:1}$ (HH:Hh:hh)

Phenotypic ratio: $\boldsymbol{3:1}$ (brown-eyed:blue-eyed)
Chances of having blue eye offspring: $\boldsymbol{25\%}$

1. Genotypic ratio: $\boldsymbol{1:2:1}$ (EE:Ee:ee)

Phenotypic ratio: $\boldsymbol{3:1}$ (free:attached)
Chances of having offspring with free-earlobes: $\boldsymbol{75\%}$

1. Genotypic ratio: $\boldsymbol{0:0:4}$ (BB:Bb:bb)

Phenotypic ratio: $\boldsymbol{0:4}$ (red-eyed:black-eyed)
Chances of red eyes mice: $\boldsymbol{0\%}$