Dihybrid crosses

Front

What is a dihybrid cross?

Back

A genetic cross that involves two traits, each represented by two alleles.

Front

What is the purpose of a Punnett square in genetics?

Back

To predict the genotypes and phenotypes of offspring from a genetic cross.

Front

What is the genotype for wrinkled seeds in pea plants?

Back

The genotype is 'rr'.

Front

What is the genotype for yellow seeds in pea plants?

Back

The genotype is 'YY' or 'Yy'.

Front

In a dihybrid cross, how many boxes are in the Punnett square?

Back

There are 16 boxes.

Front

What fraction of offspring will have the dominant phenotype for both traits in a dihybrid cross?

Back

9/16.

Front

What does the term 'allele' mean?

Back

An allele is a variant form of a gene.

Front

What is the phenotype ratio for a dihybrid cross?

Back

The phenotype ratio is 9:3:3:1.

Front

What does homozygous mean?

Back

Homozygous refers to having two identical alleles for a trait.

Front

What does heterozygous mean?

Back

Heterozygous refers to having two different alleles for a trait.