Dihybrid crosses

Front

What is a dihybrid cross?

Back

A genetic cross that examines the inheritance of two different traits, typically represented by two pairs of alleles.

Front

What does the term 'homozygous' mean?

Back

An organism that has two identical alleles for a particular trait (e.g., RR or rr).

Front

What does the term 'heterozygous' mean?

Back

An organism that has two different alleles for a particular trait (e.g., Rr).

Front

What is a Punnett square?

Back

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

Front

What is the phenotypic ratio of a dihybrid cross between two heterozygous parents (RrYy x RrYy)?

Back

9:3:3:1.

Front

What is the genotypic ratio of a dihybrid cross between two heterozygous parents (RrYy x RrYy)?

Back

1:2:1:2:4:2:1:2:1.

Front

What fraction of offspring will have round seeds if both parents are homozygous for round seeds (RR x RR)?

Back

100%.

Front

If a plant with genotype AABb is crossed with a plant with genotype AaBb, what are the possible genotypes of the offspring?

Back

AABb, AAbb, AaBb, Aabb.

Front

What is the expected phenotype of offspring from a cross between RRYY and rryy?

Back

All offspring will have round yellow seeds.

Front

In a dihybrid cross, what does the letter 'R' represent?

Back

Round seeds.