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 do the letters in a Punnett Square represent?

Back

The letters represent alleles, which are different forms of a gene. For example, 'B' may represent a dominant allele for brown eyes, while 'b' represents a recessive allele for blue eyes.

Front

What is the genotype of an organism?

Back

The genotype is the genetic makeup of an organism, represented by the combination of alleles (e.g., BB, Bb, or bb).

Front

What is the phenotype of an organism?

Back

The 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., BB or bb), while heterozygous means having two different alleles (e.g., Bb).

Front

If both parents are heterozygous (Bb), what is the probability of having a child with blue eyes?

Back

The probability is 25%.

Front

In a Punnett Square, where are the parent alleles written?

Back

The parent alleles are written outside of the boxes, typically on the top and left side.

Front

What is the purpose of a Punnett Square?

Back

The purpose of a Punnett Square is to visualize and calculate the probability of different genotypes and phenotypes in offspring.

Front

What does it mean if an organism is homozygous dominant?

Back

It means the organism has two dominant alleles for a trait (e.g., BB) and will express the dominant phenotype.

Front

What does it mean if an organism is homozygous recessive?

Back

It means the organism has two recessive alleles for a trait (e.g., bb) and will express the recessive phenotype.