Punnett Square

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 AA or aa.

Front

What does heterozygous mean?

Back

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

Front

What is the difference between dominant and recessive traits?

Back

Dominant traits are expressed when at least one dominant allele is present, while recessive traits are only expressed when two recessive alleles are present.

Front

If black fur is dominant (B) and white fur is recessive (b), what is the genotype of an organism with black fur?

Back

The genotype could be either BB (homozygous dominant) or Bb (heterozygous).

Front

What is the expected phenotypic ratio from a monohybrid cross of two heterozygous parents (Bb x Bb)?

Back

The expected phenotypic ratio is 3:1 (3 black fur: 1 white fur).

Front

How do you set up a Punnett Square?

Back

The genotypes of each parent are placed on the sides of the square, and the possible offspring genotypes are filled in the boxes.

Front

What is the genotype of an organism with white fur if white fur is recessive?

Back

The genotype would be ff (homozygous recessive).

Front

What does it mean if an organism is homozygous recessive?

Back

It means the organism has two recessive alleles for a trait, such as aa.

Front

In a Punnett Square, what does each box represent?

Back

Each box represents a possible genotype of the offspring resulting from the combination of the parents' alleles.