Pulling out the Parents in Punnett Squares

Front

What is a Punnett square used for in genetics?

Back

A Punnett square is a diagram used to predict the genotypes of offspring from a genetic cross between two parents.

Front

What does it mean for a trait to be dominant?

Back

A dominant trait is one that is expressed in the phenotype even when only one copy of the allele is present.

Front

What does it mean for a trait to be recessive?

Back

A recessive trait is one that is expressed in the phenotype only when two copies of the allele are present.

Front

What are the genotypes of two heterozygous pea plants?

Back

The genotypes are Tt and Tt.

Front

If a plant has the genotype RR, what is its phenotype?

Back

The phenotype is smooth peas, as R (smooth) is dominant over r (wrinkled).

Front

What is the genotype of a mother with freckles if her child has no freckles?

Back

The genotype of the mother is Ff, as she must carry one recessive allele to have a child without freckles.

Front

What are the possible genotypes of offspring from two heterozygous parents (Ee)?

Back

The possible genotypes are EE, Ee, and ee.

Front

In a genetic cross, what does the term 'homozygous' mean?

Back

Homozygous refers to having two identical alleles for a particular gene, either dominant (e.g., RR) or recessive (e.g., rr).

Front

In a genetic cross, what does the term 'heterozygous' mean?

Back

Heterozygous refers to having two different alleles for a particular gene (e.g., Tt).

Front

What is the phenotype of a plant with the genotype rr?

Back

The phenotype is wrinkled peas, as r (wrinkled) is recessive.