CH 9 REVIEW: Mendelian Genetics

Research during Mendel's time has established that the law of segregation during gamete formation

• applies to all asexually reproducing organisms

• applies to all forms of life

• applies to all sexually reproducing organisms

Which of the following terms refers to a situation where a single phenotypic character is determined by the additive effects of two or more genes?

• incomplete dominance

• codominance

• pleiotropy

• polygenic inheritance

A carrier of a genetic disorder who does NOT show symptoms is most likely to be ________________ to transmit it to offspring

• homozygous for the trait and unable

• homozygous for the trait and able

• heterozygous for the trait and unable

• heterozygous for the trait and able

Which of the following statements regarding genetic testing is FALSE?

• Carrier testing helps determine whether a person carries a potentially harmful disorder

• The screening of newborns can catch inherited disorders right after birth

• Genetic testing before birth requires the collection of fetal cells

• Most human genetic diseases are treatable if caught early.

Sickle cell disease is an example of

• polygenic inheritance

• a trait with more than two alleles

• autosomal recessive inheritance

Below are two statements. Which (if any) apply to the law of segregation? Which (if any) apply to the law of independent assortment?

I. Phenotypes for long tails and big eyes are inherited separately in lab mice

II. A baby mouse inherits a maternal red eye allele and a paternal black eye allele.

• I:independent assortment; II : segregation

• both segregation

• both independent assortment

• I. segregation; II independent assortment

If A is dominant to a and B is dominant to b, what is the expected genotypic ratio of the cross AaBb x AaBb?

• 9:3:3:1

• 16:0:0:)

• 1:1:1:1

• 8:4:2:2

The individual features of all organisms are the result of

• genetics and the environment

• the environment

• the environment and individual needs

• genetics

Genes located close together on the same chromosome are referred to as __________________ and generally __________.

• linked; sort independently during meiosis

• linked; do NOT sort independently during meiosis

• codependent; do not sort independently during meiosis

A testcross is

• a mating between an individual of unknown genotype and an individual homozygous for the trait of interest.

• a mating between two individuals heterozygous for the trait of interest

• a mating between an individual of unknown genotype and an individual heterozygous for the trait of interest.