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all about punnett squares

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

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all about punnett squares

Postby uchiha_sasuke » Sat Jan 28, 2006 10:21 am

i am a bit confused about punnett squares. one thing i can't understand is how those letters get there and how they got to be combined like that in the squares. also, i can't understand how to make a punnett square. all i know is make a square, cut it into four and place letters. but how am i supposed to place the letters if i don't know where (in exact place) should i put them? please help me. my teacher does not discuss it briefly and neither one of us in class understands it at all. could you please help me? :cry:
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Postby Poison » Sat Jan 28, 2006 1:35 pm

You place the letter one by one. Then you just write the combining letters form the colomn and the line. Here is an example:

Is it clear now?
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Postby Dr.Stein » Sun Jan 29, 2006 5:22 am

How many Punnett Square thread in this forum? I count there is something like four or five... hmmm :?
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Postby AM I a monkey » Mon Jan 30, 2006 4:58 am

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Thanks so much.

Postby uchiha_sasuke » Thu Feb 02, 2006 10:37 am

Thanks!!!! but i also want to ask. which is more easy to use when solving genetic problems: algebraic solutions or the punnett square?
Thanks again!
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Postby Poison » Thu Feb 02, 2006 8:00 pm

It depends on the letter (I mean the characteristic number) number you are given. If you are given like 20 letters, I don't advise you to use punnet square. :)
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a curious question.....

Postby uchiha_sasuke » Fri Feb 03, 2006 12:03 pm

could there be a difference between the two? i mean the algebraic solutions and punnett square? what if the letters are only four? which is the easiest and more advisable way?

Thanks!!!!!
:D
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Postby MrMistery » Fri Feb 03, 2006 12:52 pm

well the punnet sqaure will probably take you more time. If you have 4 alleles it will take you some time. But punnet squares guarantee accuracy, unlike algebra where you can easily make a mistake(like me)
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Postby Poison » Fri Feb 03, 2006 8:03 pm

The results will be the same, if you don't make mistake. Well, I don't like maths. So if the letter number is 4 I advice you to use punnet square. Maybe it may take some time, but, as Andrew said the probability of making mistake when using punnet square is less than the other.
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hmmmm...........

Postby uchiha_sasuke » Sat Feb 04, 2006 4:08 am

another question. if i am performing a dihybrid cross, which shoul i prefer to use: punnet square or the algebra? i am not that fond in math but i've got good grades mind you. :wink: 8)
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Postby M.Shanti Priya » Sat Feb 04, 2006 8:02 am

For a dihybrid cross you can use punnett square. From trihybrid better to go for dichotomous / branching method.
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Postby uchiha_sasuke » Sat Feb 04, 2006 9:27 am

what's a dichotomous / branching method? i've never heard of it, sorry. could you explain it please?!
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