What is a punnett square?


(This is a punnett square)
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Which kids belong to which couples?
The Punnett square is a diagram that is used to predict the outcome of a particular cross or breeding experiment.
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This shows an eye color cross between a male and female

A punnett square uses probability to determine the possible traits of offspring.

Genetics Practice Problems

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Punnett Square quiz link

The letters in a punnett square are called the genotype.  The way the offspring looks is called the phenotype.


Capital letters are dominant. Lower case letters are recessive.
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How are punnett squares like probability?

Sooo, how do punnett squares use probability?

The answer is that they can be used as predictive tools when considering having children.  Punnett squares are standard tools used by genetic counselors.  Theoretically, the likelihood of inheriting many traits, including useful ones, can be predicted using them.   It is also possible to construct squares for more than one trait at a time.

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