AP Biology Genetics Review

Front

What is a sex-linked allele?

Back

A gene located on a sex chromosome, often affecting traits related to gender.

Front

How do sex-linked traits get passed from father to children?

Back

A father passes his sex-linked alleles to all of his daughters and none to his sons.

Front

What is non-disjunction in genetics?

Back

The failure of homologous chromosomes or sister chromatids to separate properly during cell division, leading to gametes with abnormal chromosome numbers.

Front

What does an XXY genotype indicate in humans?

Back

It indicates a male with Klinefelter syndrome, characterized by the presence of an extra X chromosome.

Front

What is hemophilia?

Back

A genetic disorder caused by a deficiency in clotting factors, leading to excessive bleeding, often inherited in an X-linked recessive pattern.

Front

What does it mean for a trait to be X-linked recessive?

Back

A trait that is carried on the X chromosome and expressed in males who have only one X chromosome, while females need two copies to express the trait.

Front

What are multiple alleles?

Back

More than two alternative forms of a gene that can exist in a population.

Front

What is a pedigree chart?

Back

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

Front

What is the expected ratio of affected males to females in a sex-linked trait?

Back

More affected males than females, due to the inheritance pattern of X-linked traits.

Front

What is a carrier in genetics?

Back

An individual who has one copy of a recessive allele that does not manifest in their phenotype but can be passed to offspring.