## Punnett Squares

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

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xllxashleexllx
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### Punnett Squares

I have to do punnett squares on one of my exams but i dont understand them. Could someone help????

Thank You
Ashlee

mith
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do a forum search, we have many examples.
search.php
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xllxashleexllx
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OK thank you

Ashlee

xllxashleexllx
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Ok I looked at them did i do this right?

the first one is Rrtt
Rt tr
Rt tr

the second one is rrTt
rt Tr
rt tr

Are they right???

Ashlee

Dr.Stein
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You need to be consistent, when you place R or r in the first place, then it should be always there

bearhug
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Have you ever heard of the FOIL method in math? If it helps use that same method for monohybrid cross.
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xllxashleexllx
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no what is the FOIL method?

Ashlee

mith
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http://www.algebrahelp.com/lessons/simp ... oilmethod/

If you think about it, a punnet square is just a 2X2 multiplcation table.
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Enzyme
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### Re: Punnett Squares

xllxashleexllx wrote:I have to do punnett squares on one of my exams but i dont understand them. Could someone help????

Thank You
Ashlee

Punnet squares show the allelic combinations of the gametes of each parental and say the possible proportions of the offspring. In one of the axis of the square, you have to put the gametes of one parental and in the other axis you have to put the gametes of the other parental. Then, you have to do the combinations and to write them in their corresponding spaces in the Punnet square.

Here you have an example:
Attachments
dihybridtestcross.gif
(30.95 KiB) Downloaded 301 times

MariaNovoa
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please!!!!!!!!!! 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
>MaRia NovOa<

Poison
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No need to double-post things. I think Enzyme's post explains it. There are some more topics too. Search the forum.
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Dr.Stein
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MariaNovoa wrote:please!!!!!!!!!! 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

How could you don't understand the punnet square? What were you doing in class? You can ask your teacher, classmates, you can study together. I am sure they would like to help you. I only can wish you a good luck

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