Pedigrees

Front

What is a pedigree?

Back

A pedigree is a diagram that shows the occurrence and appearance of phenotypes of a particular gene or organism and its ancestors.

Front

What does it mean if a trait is dominant?

Back

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

Front

What does it mean if a trait is recessive?

Back

A recessive trait only appears in the phenotype if two copies of the allele are present.

Front

How can you identify a carrier in a pedigree?

Back

A carrier is an individual who has one copy of a recessive allele and does not exhibit the trait but can pass it to offspring.

Front

What is the phenotype of an individual with genotype 'aa'?

Back

The phenotype is recessive, meaning the individual expresses the recessive trait.

Front

What is the phenotype of an individual with genotype 'AA'?

Back

The phenotype is dominant, meaning the individual expresses the dominant trait.

Front

What is the phenotype of an individual with genotype 'Aa'?

Back

The phenotype is dominant, as the presence of one dominant allele results in the expression of the dominant trait.

Front

What does it mean for a trait to skip a generation?

Back

It means that the trait may not be expressed in one generation but can appear in the next, often seen with recessive traits.

Front

What is cystic fibrosis?

Back

Cystic fibrosis is a genetic disorder that affects the lungs and digestive system, characterized by the production of thick mucus.

Front

What is albinism?

Back

Albinism is a genetic condition characterized by a deficiency of pigmentation in the skin, hair, and eyes.