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 recessive?

Back

A recessive trait is one that requires two copies of the allele (one from each parent) to be expressed in the phenotype.

Front

What is the genotype for a person with Cystic Fibrosis?

Back

The genotype for a person with Cystic Fibrosis is 'cc', indicating they have two recessive alleles.

Front

What is the genotype for a person who is a carrier of Cystic Fibrosis?

Back

The genotype for a carrier of Cystic Fibrosis is 'Cc', meaning they have one normal allele and one recessive allele.

Front

What does it mean if a trait is dominant?

Back

A dominant trait is one that is expressed in the phenotype even if only one copy of the allele is present.

Front

What is the genotype for a person with straight thumbs?

Back

The genotype for a person with straight thumbs can be either 'TT' (homozygous dominant) or 'Tt' (heterozygous).

Front

What is the genotype for a person with hitchhiker's thumb?

Back

The genotype for a person with hitchhiker's thumb is 'tt', indicating they have two recessive alleles.

Front

How can you determine the number of females in a pedigree?

Back

Count the circles in the pedigree diagram, as circles represent females.

Front

What is the significance of using a pedigree in genetics?

Back

Pedigrees help track the inheritance patterns of traits and can indicate the likelihood of genetic disorders.

Front

What does 'TT' represent in genetics?

Back

'TT' represents a homozygous dominant genotype for a trait.