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A geneticist is aiming to obtain a variety of quorn that has particular attributes.
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In order to understand inheritance of particular traits, they perform a series of genetic cross tests.
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Quorn with the genotype wxsh, this plant is wild type.
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And a heterozygous plant was test crossed with plants with waxy and shriveled, which is actually homozygous recessive.
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Now the genes are linked and there are 32 map unit parts, 400 proteins obtained.
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How many of you expect to have the waxy phenotype but not shriveled? so since these two genes are linked, there are two possible ways.
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So let's say first way, parental.
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So that means for the parent, there's no recombinant between the two genes wx and sh.
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So there's no crossover.
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So if we look at the chromosome arrangement, wx plus sh plus wxsh.
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And it crossed with the other parents, homozygous recessive, wxsh, wxsh.
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So this is called the parental.
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There's no crossover between wxg and sh.
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So as a result, you will produce f1, one of the chromosome is wx plus sh plus.
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Now it picks up another chromosome from the other parents, wxsh.
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Or you get the other chromosome, wxsh.
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And then the other chromosome, wxsh.
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So you can see that these two are called parental progeny.
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If we look at the phenotype, this is complete wild type.
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And this is waxy and shrivel.
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The second kind we call the recombinant.
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Because the two genes are linked, sometimes their recombinant are a crossover between the two genes.
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So this come from the crossover parent or gametes.
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So you can see the crossover happens like this, wx plus sh plus wxsh.
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So there is a crossover between the genes.
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So now the new combination is wx plus versus sh and wx versus sh plus.
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And then you again cross with homozygous recessive wxsh, wxsh.
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As a result, you will produce recombinant f1, the different kind...