Punnett Square Practice

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 'dominant' mean in genetics?

Back

A dominant allele is one that expresses its trait even when only one copy is present in the genotype.

Front

What does 'recessive' mean in genetics?

Back

A recessive allele is one that only expresses its trait when two copies are present in the genotype.

Front

What is a genotype?

Back

A genotype is the combination of alleles (letters) that an organism has for a specific trait.

Front

What is a phenotype?

Back

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

Front

What is the difference between homozygous and heterozygous?

Back

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

Front

What is the expected phenotype ratio from a cross of Bb x Bb?

Back

The expected phenotype ratio is 3:1, with 3 showing the dominant trait and 1 showing the recessive trait.

Front

What is the expected genotype ratio from a cross of Bb x Bb?

Back

The expected genotype ratio is 1:2:1, with 1 homozygous dominant (BB), 2 heterozygous (Bb), and 1 homozygous recessive (bb).

Front

What does 'true-breeding' mean?

Back

True-breeding refers to organisms that, when mated, produce offspring that are identical to themselves for a specific trait.

Front

What is the purpose of a test cross?

Back

A test cross is used to determine the genotype of an organism showing a dominant phenotype by crossing it with a homozygous recessive.