Punnett Squares

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 'dominant' mean in genetics?

Back

A dominant allele is one that expresses its trait even when only one copy is present in the genotype.

Front

What does 'recessive' mean in genetics?

Back

A recessive allele is one that only expresses its trait when two copies are present in the genotype.

Front

In a heterozygous genotype, which allele is expressed in the phenotype?

Back

The dominant allele.

Front

If B = brown fur and b = white fur, what is the probability of getting brown fur from a Bb x Bb cross?

Back

75%.

Front

What is the genotype for a short plant if tall (T) is dominant to short (t)?

Back

tt.

Front

What is the probability of producing a short plant from a Tt x Tt cross?

Back

25%.

Front

What does it mean if an organism is homozygous?

Back

An organism is homozygous if it has two identical alleles for a trait.

Front

What does it mean if an organism is heterozygous?

Back

An organism is heterozygous if it has two different alleles for a trait.

Front

What is the purpose of a Punnett Square?

Back

To visualize and calculate the probability of different genotypes and phenotypes in offspring.