Punnett Squares

Front

What is a Punnett Square?

Back

A Punnett Square is a diagram used to predict the outcome of a genetic cross by showing the possible combinations of alleles from the parents.

Front

What does homozygous mean?

Back

Homozygous refers to having two identical alleles for a particular gene, such as TT or tt.

Front

What does heterozygous mean?

Back

Heterozygous refers to having two different alleles for a particular gene, such as Tt.

Front

What is a dominant allele?

Back

A dominant allele is an allele that expresses its trait even when only one copy is present, represented by a capital letter.

Front

What is a recessive allele?

Back

A recessive allele is an allele that only expresses its trait when two copies are present, represented by a lowercase letter.

Front

How many alleles does a person carry for each trait?

Back

Each person carries two alleles for each trait, one inherited from each parent.

Front

What is the genotype?

Back

The genotype is the genetic makeup of an organism, represented by the alleles it possesses (e.g., TT, Tt, tt).

Front

What is the phenotype?

Back

The phenotype is the observable physical or biochemical characteristics of an organism, determined by its genotype.

Front

What is the probability of getting a blue-eyed child from two brown-eyed parents (Bb)?

Back

The probability is 25%, as shown in a Punnett Square.

Front

What does it mean if an organism is purebred?

Back

A purebred organism has a homozygous genotype, meaning it has two identical alleles for a trait.