Unit 6 Test Retake: The Human Genome - 5th Period

Front

What is an autosomal dominant trait?

Back

An autosomal dominant trait is a genetic trait that is expressed when at least one dominant allele is present. It can be inherited from one parent who carries the dominant allele.

Front

What does a shaded symbol represent in a pedigree chart?

Back

A shaded symbol in a pedigree chart represents an individual who expresses the dominant trait being studied.

Front

What are the possible genotypes for an individual expressing an autosomal dominant trait?

Back

The possible genotypes are either homozygous dominant (AA) or heterozygous (Aa).

Front

What is the genotype of an individual who does not express an autosomal dominant trait?

Back

The genotype of an individual who does not express the trait is homozygous recessive (aa).

Front

What is a Punnett square used for?

Back

A Punnett square is a diagram used to predict the genotypes of offspring from a genetic cross.

Front

What does X-linked recessive mean?

Back

X-linked recessive refers to a trait that is associated with a gene located on the X chromosome and is expressed in individuals who have one or two copies of the recessive allele.

Front

What is the probability of a son inheriting an X-linked recessive trait from a mother who is a carrier?

Back

The probability is 50% if the father does not have the trait.

Front

What is the significance of the genotype 'Hh' in relation to recessive disorders?

Back

The genotype 'Hh' indicates that the individual is a carrier of the recessive disorder but does not express the disorder.

Front

What is the chance of daughters inheriting an X-linked recessive disorder if the father has the disorder?

Back

Daughters have a 100% chance of being carriers if the father has the disorder, but the chance of expressing the disorder depends on the mother's genotype.

Front

What does it mean if a pedigree shows a recessive disorder?

Back

It means that individuals expressing the disorder must have two copies of the recessive allele (hh).