Punnett Squares 2

Front

What is a Punnett Square?

Back

A Punnett Square is a diagram used to predict the genetic makeup of offspring from two parents based on their genotypes.

Front

What does heterozygous mean?

Back

Heterozygous refers to having two different alleles for a particular gene, such as Aa.

Front

What does homozygous mean?

Back

Homozygous refers to having two identical alleles for a particular gene, such as AA or aa.

Front

If one parent is homozygous dominant (AA) and the other is heterozygous (Aa), what are the possible genotypes of the offspring?

Back

The possible genotypes are 50% AA and 50% Aa.

Front

What is the probability of a child being homozygous recessive (aa) if both parents are heterozygous (Aa)?

Back

The probability is 25%.

Front

In a Punnett Square, what does each box represent?

Back

Each box represents a possible genotype of the offspring based on the alleles contributed by each parent.

Front

What is the chance of offspring being square-shaped if one parent is heterozygous (Ss) and the other is round (ss)?

Back

The chance is 50%.

Front

If both parents are heterozygous (Aa) for a trait, what is the chance of having a homozygous dominant (AA) child?

Back

The chance is 25%.

Front

What is the expected phenotype ratio from a cross between two heterozygous parents (Aa x Aa)?

Back

The expected phenotype ratio is 3:1.

Front

If Mr. Krabbs is homozygous for tall eyeballs (TT) and his wife is heterozygous (Tt), what is the chance their child will have tall eyeballs?

Back

The chance is 100%.