Punnett squares

Punnett Squares

Biology meets probability

What are they?

Punnett squares were devised by and named for Reginald Punnett. They show possible combinations of maternal and paternal alleles.

What are the odds?

In the Punnett square to the right, the possible allele combinations are shown. They are: 

50% chance of Yy genotype
50% chance of yy genotype

So, if an offspring were to be produced by these parents, these are the possible alleles that the offspring will inherit.

Multiple Choice

For this Punnett square, what are the chances of the offspring inheriting the Aa genotype?

• 0%

• 25%

• 50%

• 100%

Multiple Choice

For this Punnett square, what are the chances that an offspring will have a homozygous recessive trait?

• 0%

• 25%

• 50%

• 100%

Multiple Choice

For this Punnett square, which genotype will an offspring most likely inherit?

• RR

• Rr

• rr

Head to the following link

https://www.youtube.com/watch?v=BRMcTdKNpOA

Two-trait Punnett Squares

Punnett squares can also represent crosses of two traits, where pairs of alleles from each parent will be passed on to offspring.

Fill in the Blanks

A Punnett square shows the chances of a(n)

inheriting certain traits from its parent(s).

Open Ended

For this Punnett square: if C = checkered, c = striped, P = purple and p = pink, what are the chances that the offspring will be checkered and purple? (Remember - capital alleles are dominant)

Open Ended

For the Punnett square, write down all possible genotypes and their chances of occurring in offspring.

Open Ended

For the Punnett square, write down all possible genotypes and their chances of occurring in offspring.

Poll

Did you want some lessons in the future to be run through Quizizz like this one was?

• Yes

• No