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 dominant mean?

Back

Homozygous dominant refers to having two identical dominant alleles for a trait, represented as 'AA'.

Front

What does heterozygous mean?

Back

Heterozygous means having two different alleles for a trait, represented as 'Aa'.

Front

What does homozygous recessive mean?

Back

Homozygous recessive refers to having two identical recessive alleles for a trait, represented as 'aa'.

Front

In a Punnett Square, what does each box represent?

Back

Each box represents a 25% probability of an offspring's genotype.

Front

If one parent is homozygous dominant (AA) and the other is homozygous recessive (aa), what are the possible genotypes of the offspring?

Back

All offspring will be heterozygous (Aa).

Front

What is the genotype ratio from a cross between two heterozygous parents (Aa x Aa)?

Back

The genotype ratio is 1 AA : 2 Aa : 1 aa.

Front

What is the phenotype ratio from a cross between two heterozygous parents (Aa x Aa) if 'A' is dominant for tall and 'a' is recessive for short?

Back

The phenotype ratio is 3 tall : 1 short.

Front

What is the purpose of using a Punnett Square?

Back

The purpose is to predict the genetic makeup of offspring from a particular cross.

Front

What is an allele?

Back

An allele is a variant form of a gene that determines a specific trait.