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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

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?

uchiha_sasuke
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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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Poison
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How many Punnett Square thread in this forum? I count there is something like four or five... hmmm

Dr.Stein
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Thanks so much.

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!

uchiha_sasuke
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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.
It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.

Poison
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a curious question.....

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!!!!!

uchiha_sasuke
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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)
"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

MrMistery
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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.
It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.

Poison
Inland Taipan

Posts: 2322
Joined: Sun Jan 02, 2005 12:44 pm
Location: Turkey

hmmmm...........

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.

uchiha_sasuke
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For a dihybrid cross you can use punnett square. From trihybrid better to go for dichotomous / branching method.
M.Shanti Priya
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what's a dichotomous / branching method? i've never heard of it, sorry. could you explain it please?!

uchiha_sasuke
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