Punnett Square Practice

Front

What is a Punnett Square?

Back

A Punnett Square is a diagram used to predict the genetic makeup of offspring from a cross between two parents.

Front

What does homozygous mean?

Back

Homozygous refers to having two identical alleles for a particular gene, either dominant or recessive.

Front

What does heterozygous mean?

Back

Heterozygous refers to having two different alleles for a particular gene, one dominant and one recessive.

Front

What is the probability of an offspring being homozygous dominant if both parents are heterozygous?

Back

25%.

Front

What is the probability of an offspring being homozygous recessive if both parents are heterozygous?

Back

25%.

Front

If one parent is homozygous dominant and the other is homozygous recessive, what is the chance of offspring being heterozygous?

Back

100%.

Front

What is the chance that the offspring will have a recessive trait if both parents are heterozygous?

Back

25%.

Front

What does it mean if a trait is dominant?

Back

A dominant trait is one that will express itself in the phenotype even if only one allele is present.

Front

What does it mean if a trait is recessive?

Back

A recessive trait is one that will only express itself in the phenotype if both alleles are recessive.

Front

How do you determine the genotype of an offspring using a Punnett Square?

Back

By filling in the Punnett Square with the alleles from each parent and analyzing the resulting combinations.