Dihybrid crosses

Front

What is a dihybrid cross?

Back

A genetic cross that examines the inheritance of two different traits, typically involving two pairs of contrasting traits.

Front

What does the term 'homozygous' mean?

Back

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

Front

What does the term 'heterozygous' mean?

Back

An organism that has two different alleles for a particular gene (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?

Back

The typical phenotypic ratio for a dihybrid cross is 9:3:3:1.

Front

What is the genotypic ratio of a dihybrid cross?

Back

The typical genotypic ratio for a dihybrid cross is 1:2:1:2:4:2:1:2:1.

Front

What is the probability of obtaining a homozygous recessive offspring from a dihybrid cross?

Back

The probability is determined by the specific alleles involved, but typically it is low.

Front

If RRYY is crossed with rryy, what will the offspring's genotype be?

Back

All offspring will be RrYy.

Front

What is the expected percentage of offspring with round and yellow seeds from a cross of RRYY x rryy?

Back

100% will have round and yellow seeds.

Front

In a dihybrid cross, what does the term 'dominant' refer to?

Back

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