Test cross - Independent Assortment and Segregation???

Genetics as it applies to evolution, molecular biology, and medical aspects.

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student12
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Test cross - Independent Assortment and Segregation???

Post by student12 » Wed Aug 23, 2006 11:00 am

In my texts it states that test crosses are used to determine wether the individual showing the dominant phenotype is homozygous or heterozygous.
It also states that it demonstrates the Principle of Independent Assortment and Principle of Segregation. (this is where I don't understand)

The outcomes of a test cross is always 1:1 phenotypic ratio. The only relationship i see is that the Principle of Independent Assortment applies for a cross b/t 2 or more genetic loci, and that the Principle of Segregation applies for a cross involving 1 genetic locus.

So what is the point of a test cross on this matter...???
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weesper
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Post by weesper » Wed Aug 23, 2006 1:25 pm

Both these principles state that the crosses conform to general mendelian rules; independent assortment means that the two loci are not linked and are indepently assorted over the F1 generationa.

student12
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Post by student12 » Fri Aug 25, 2006 10:22 am

Is there a reason why my text only refers to the Principle of Independent Assortment in test crosses involving 2 genetic loci, and Principle of Segregation to testc crosses involving 1 genetic loci?

b/c the way i interpret from weesper's message is that both these events occur in both crosses involving 1 and 2 genetic loci.

Am i right?

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Sepals
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Post by Sepals » Mon Aug 28, 2006 4:08 pm

No offence Student12 you should look this stuff up before starting mutliple threads asking ppl to answer your hw questions. Loads of sites (possibly inc this one) and textboooks can help.
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student12
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Post by student12 » Thu Sep 14, 2006 8:05 am

hmmm...to be honest these questions are not for homework...these questions are of my own interests, and are confusing me. Therefore, I ask these questions, in hope of finding an answer from those who are more experienced and possibly encontoured these queries already. I am here in search of knowledge.

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