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 are the possible genotypes for a dihybrid cross of two heterozygous parents (AaBb x AaBb)?

Back

The possible genotypes are: AABB, AABb, AAbb, AaBB, AaBb, Aabb, aaBB, aaBb, aabb.

Front

What is the phenotypic ratio expected from a dihybrid cross of two heterozygous parents?

Back

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

Front

Define homozygous and heterozygous genotypes.

Back

Homozygous genotypes have two identical alleles for a trait (e.g., AA or aa), while heterozygous genotypes have two different alleles (e.g., Aa).

Front

If 'T' is tall and 't' is short, what is the phenotype of a plant with genotype Tt?

Back

The phenotype of a plant with genotype Tt is tall.

Front

What does the term 'allele' mean?

Back

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

Front

In a dihybrid cross, what does the F1 generation represent?

Back

The F1 generation represents the first filial generation, which is the offspring of the parental generation.

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.

Front

What is the significance of the 9:3:3:1 ratio in dihybrid crosses?

Back

The 9:3:3:1 ratio indicates the expected distribution of phenotypes in the offspring when two traits are independently assorted.

Front

What is the genotype of a yellow plant if 'G' is green and 'g' is yellow?

Back

The genotype of a yellow plant is gg.