Punnett Square Practice

Front

What is a Punnett Square?

Back

A Punnett Square is a diagram used to predict the outcome of a genetic cross by showing the possible combinations of alleles from the parents.

Front

What does heterozygous mean?

Back

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

Front

What does homozygous mean?

Back

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

Front

What is the genotype of a plant with purple flowers that is heterozygous?

Back

The genotype is Pp.

Front

What is the phenotype of a plant with the genotype pp?

Back

The phenotype is white flowers.

Front

If two heterozygous plants (Pp) are crossed, what is the expected ratio of phenotypes in the offspring?

Back

The expected ratio is 3:1 for purple to white flowers.

Front

What is the probability of getting a homozygous recessive offspring (pp) from a Pp x Pp cross?

Back

The probability is 25% or 1:4.

Front

What are alleles?

Back

Alleles are different forms of a gene that can exist at a specific locus on a chromosome.

Front

What does it mean if a trait is dominant?

Back

A dominant trait is one that is expressed in the phenotype even if only one allele is present.

Front

What does it mean if a trait is recessive?

Back

A recessive trait is one that is expressed in the phenotype only when two copies of the allele are present.