Punnett Squares and Pedigrees

Front

What is a phenotype?

Back

A phenotype is the observable physical or biochemical characteristics of an organism, as determined by both genetic makeup and environmental influences. Example: red hair.

Front

What is a genotype?

Back

A genotype is the genetic constitution of an individual, often represented by letters (e.g., Aa, AA, aa). It determines the potential traits of an organism.

Front

What does a Punnett square illustrate?

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 is the difference between dominant and recessive alleles?

Back

Dominant alleles are expressed in the phenotype even if only one copy is present (e.g., A), while recessive alleles are only expressed if two copies are present (e.g., aa).

Front

How is a dominant allele represented?

Back

A dominant allele is represented by a capital letter (e.g., A).

Front

How is a recessive allele represented?

Back

A recessive allele is represented by a lowercase letter (e.g., a).

Front

What does an open circle represent in a pedigree chart?

Back

An open circle represents a Not Affected Female in a pedigree chart.

Front

What does a shaded circle represent in a pedigree chart?

Back

A shaded circle represents an Affected Female in a pedigree chart.

Front

What does a shaded square represent in a pedigree chart?

Back

A shaded square represents an Affected Male in a pedigree chart.

Front

What is the purpose of a pedigree chart?

Back

A pedigree chart is used to track the inheritance of traits through generations in a family.