Dihybrid Crosses

Front

What is a dihybrid cross?

Back

A dihybrid cross is a genetic cross that examines the inheritance of two different traits, each controlled by different genes.

Front

What does the genotype AaPp represent?

Back

The genotype AaPp indicates that the organism is heterozygous for both traits, with one dominant and one recessive allele for each gene.

Front

What gametes can be produced from the genotype AaPp?

Back

The possible gametes are AB, Ab, aB, and ab.

Front

What is the phenotypic ratio expected from a dihybrid cross of two heterozygous parents (AaBb x AaBb)?

Back

The expected phenotypic ratio is 9:3:3:1.

Front

What is the significance of homozygous and heterozygous genotypes in dihybrid crosses?

Back

Homozygous genotypes have identical alleles, while heterozygous genotypes have different alleles, affecting the offspring's traits.

Front

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

Back

All offspring will be RrYy, showing round yellow seeds.

Front

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

Back

100% of the offspring will have round and yellow seeds.

Front

What does the term 'allele' mean?

Back

An allele is a variant form of a gene that can produce different traits.

Front

How do you determine the gametes from a genotype like TtZz?

Back

The gametes can be determined by combining one allele from each gene: TZ, Tz, tZ, and tz.

Front

What is the purpose of a Punnett square in genetics?

Back

A Punnett square is used to predict the genotypes and phenotypes of offspring from a genetic cross.