How to get the genotype and phenotype ratio!!

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

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MariaNovoa
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How to get the genotype and phenotype ratio!!

Post by MariaNovoa » Sun Jan 22, 2006 9:09 pm

please!!!!!!!!!! :shock: i have a test 2morrow in my biology class and i dont understand the punnet square! i understand that the capital letter is Dominant and the lower case letter is reccessive, i also understand that genotype is the genetic makeup and phenotype is the physical characteristes, i got the concepts clear. but what does dominant and recessive has to do with genotype and phenotype, how do i place the letters in the punnet square and how do i get the ratios! please help me!
Email me or aim at [email protected] or at my email address [email protected]!...PLEASE HELP ME

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mith
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Post by mith » Mon Jan 23, 2006 2:26 am

do a forum search, you're not the only one.
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Enjoying one moment at a time;
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Post by Hovergoat » Thu Feb 02, 2006 2:31 am


M.Shanti Priya
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Post by M.Shanti Priya » Thu Feb 02, 2006 9:45 am

In the punnett square on right top you write the gametes from one parent (male or female) and on the left side you write the gametes from other parent (female or male). While writing the gametes be careful that in a gamete a gene is represented only by one allele (either recessive or dominant). In the squares you combine the gamete from male and female and give the progeny (in progeny each gene is represented by two alleles ). Now for the progeny based on the presence or absence of dominant allele give the phenotypes. ex if (female) Aa is crossed with (male) AA
A (male gives only one type of gamete)
A AA

a Aa

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Dr.Stein
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Post by Dr.Stein » Fri Feb 03, 2006 8:13 am

Oh I am lazy to read paragraph :P :oops:
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Jwright
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Post by Jwright » Fri Feb 17, 2006 1:08 am

yea i have probs with phenotype i get genotype and its makin me mad.....(_(_)
IF HEAVEN WAS A MILE AWAY, WOULD U PACK YOUR BAGS AND LEAVE THIS WORLD BEHIND?

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Dr.Stein
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Post by Dr.Stein » Mon Feb 20, 2006 6:54 am

Calm down, we can help you. Which part makes you confused? ;)
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