Dihybrid Punnett Squares & MORE!

Front

What is incomplete dominance?

Back

A genetic situation in which one allele does not completely dominate another allele, resulting in a new phenotype that is a blend of the two traits.

Front

How many offspring are produced in a dihybrid cross?

Back

16 offspring.

Front

What do half-colored symbols represent in a pedigree chart?

Back

The individual is a carrier of the trait.

Front

In a dihybrid cross, what fraction of the offspring will have a specific phenotype if the ratio is 9:3:3:1?

Back

3/16 will have the specified phenotype.

Front

Why do X-linked traits like hemophilia affect males more often than females?

Back

Males have only one copy of the X chromosome, so if they inherit the recessive allele, they will express the trait.

Front

What is a Punnett Square?

Back

A diagram used to predict the outcome of a particular cross or breeding experiment.

Front

Define codominance.

Back

A genetic scenario where both alleles in a heterozygote are fully expressed, resulting in offspring with a phenotype that is neither dominant nor recessive.

Front

What is the phenotypic ratio of a dihybrid cross?

Back

9:3:3:1.

Front

What does it mean if an individual has two recessive alleles?

Back

The individual expresses the recessive trait.

Front

What is the purpose of a test cross?

Back

To determine the genotype of an individual showing a dominant phenotype by crossing it with a homozygous recessive individual.