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 the term 'genotype' refer to?

Back

Genotype refers to the genetic makeup of an organism, specifically the alleles it possesses for a particular trait.

Front

What is a heterozygous genotype?

Back

A heterozygous genotype has two different alleles for a trait, such as Bb.

Front

What is a homozygous genotype?

Back

A homozygous genotype has two identical alleles for a trait, such as BB or bb.

Front

What is a dominant allele?

Back

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

Front

What is a recessive allele?

Back

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

Front

If one parent is homozygous dominant (BB) and the other is homozygous recessive (bb), what will be the genotype of the offspring?

Back

All offspring will be heterozygous (Bb).

Front

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

Back

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

Front

In a Punnett Square, what do the letters on the top and side represent?

Back

The letters on the top represent the alleles from one parent, and the letters on the side represent the alleles from the other parent.

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 bb.