Dihybrid Crosses

Front

What is a dihybrid cross?

Back

A genetic cross between individuals that examines the inheritance of two different traits, each controlled by different genes.

Front

What does the term 'homozygous' mean?

Back

An organism with two identical alleles for a particular trait (e.g., RR or rr).

Front

What does the term 'heterozygous' mean?

Back

An organism with two different alleles for a particular trait (e.g., Rr).

Front

What is the genotype for a pea plant heterozygous for round seeds (R) and homozygous recessive for green seeds (y)?

Back

Rryy

Front

In a dihybrid cross, what is the phenotypic ratio for the offspring?

Back

9:3:3:1 ratio for dominant and recessive traits.

Front

What is the genotype for a pea plant homozygous for round seeds (R) and heterozygous for yellow seeds?

Back

RRYy

Front

What is the probability of obtaining a homozygous recessive offspring from a cross between two heterozygous parents (Rr x Rr)?

Back

25%.

Front

What is the expected phenotypic ratio when crossing two heterozygous plants (RrYy x RrYy)?

Back

9:3:3:1.

Front

What is the significance of a Punnett square in genetics?

Back

A tool used to predict the genotypes and phenotypes of offspring from a genetic cross.

Front

What is the genotype for a pea plant homozygous recessive for round seeds and heterozygous for yellow seeds?

Back

rrYy