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Study the pedigree

How does this disease (filled symbols) inherit?

How does this disease (filled symbols) inherit?

A

dominant

B

recessive

C

can't be determined

This is the same pedigree as the previous question.

At first the disease looks to be sex-linked

Give an argument why.

At first the disease looks to be sex-linked

Give an argument why.

Same pedigree again.

The question is if the disease is actually sex-linked.

Can we determine that with 100% confidence from this pedigree?

The question is if the disease is actually sex-linked.

Can we determine that with 100% confidence from this pedigree?

A

yes, it is autosomal

B

yes, it is sex-linked

C

we can't say for sure, but are allowed to assume sex-linked

A tortoiseshell is crossed with a black male.

What is the chance of the female offspring being tortoiseshell? Show the Punnett square.

What is the chance of the female offspring being tortoiseshell? Show the Punnett square.

See the cross in the image

Colour: A = black; a = red

Pattern: B = solid; b = patches

What is the genotype of the red-patched bull?

What can be the genotype(s) of the solid black cow?

Colour: A = black; a = red

Pattern: B = solid; b = patches

What is the genotype of the red-patched bull?

What can be the genotype(s) of the solid black cow?

Write down all possible genotypes for the sperm cells of this bull (AaBb)

Write down all possible genotypes of the egg cells of this cow (AABB).

Do the same for the sperm cells of the bull (aabb)

What is the genotype of all offspring in the F1?

Do the same for the sperm cells of the bull (aabb)

What is the genotype of all offspring in the F1?

We take a cow and a bull from the F1 and cross them to create the F2.

Write down the Punnett square for this and upload below:

Write down the Punnett square for this and upload below:

What is the phenotype ratio in this F2?

Step 1: Determine the genotypes of the P generation

P. long, smooth leaves x short, serrated leaves

F1. 100% long, serrated leaves

What are the genotypes of the parents?

P. long, smooth leaves x short, serrated leaves

F1. 100% long, serrated leaves

What are the genotypes of the parents?

Step 2: Determine the genotypes of the F1 generation

P. long, smooth leaves x short, serrated leaves

F1. 100% long, serrated leaves

What are the genotypes in the F1?

P. long, smooth leaves x short, serrated leaves

F1. 100% long, serrated leaves

What are the genotypes in the F1?

Step 3: Determine the chance in the F2 for both traits separate.

First trait: leaf length

F1: Ll x Ll

What is the chance of long leaves in the F2?

First trait: leaf length

F1: Ll x Ll

What is the chance of long leaves in the F2?

Step 3: Determine the chance in the F2 for both traits separate.

First trait: leaf: leaf edge

F1: Ee x Ee

What is the chance of smooth leaves in the F2?

First trait: leaf: leaf edge

F1: Ee x Ee

What is the chance of smooth leaves in the F2?

Step 4: Multiply these chances with each other

What is the chance of long and smooth leaves?

Show your calculation

What is the chance of long and smooth leaves?

Show your calculation

Let's start with coat colour

What is the (approximately) the phenotype ratio of the offspring?

What is the (approximately) the phenotype ratio of the offspring?

If the phenotype ratio is 1:1, what MUST the genotypes of the parents be? (use the letter A)

Now for the ears

What is the phenotype ratio of the offspring and what should the genotypes of the parents therefore be?

What is the phenotype ratio of the offspring and what should the genotypes of the parents therefore be?

What are the genotypes and phenotypes of the parents?