Ch. 9 - Genetics Quiz

The physical traits of an organism are called its ______.

• phenotype

• allele

• genotype

• gene

Alleles are described as ______.

• alternate versions of a gene

• homologous chromosomes

• alternate phenotypes

• environmental factors that affect gene expression

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

In humans, the presence or absence of dimples is a trait controlled by a single gene. What is the genotype of an individual who is heterozygous for dimples?

• dd

• Dd

• DD

• DI

An individual who is homozygous ______.

• carries two copies of the same allele for a gene

• expresses the recessive trait

• expresses the dominant trait

• carries two different alleles for a gene

Tags

NGSS.HS-LS3-1

A purebred plant that produces yellow seeds is crossed with a purebred plant that produces green seeds. The seeds of all of the offspring are yellow. Why?

• All of the offspring are homozygous yellow.

• The alleles are codominant.

• The yellow allele is dominant to the green allele.

• The yellow allele is recessive to the green allele

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Incomplete dominance is a condition in plants and people where ______.

• multiple alleles are responsible for an inheritance pattern

• a single gene impacts more than one characteristic

• offspring have an appearance in between the phenotypes of the two parents

• most heritable diseases arise

You cross a true-breeding red-flowered snapdragon with a true-breeding white-flowered snapdragon. All of the F1 are pink. What can you say about the alleles for the parental traits?

• Both red and white are recessive.

• Red and white show incomplete dominance.

• Pink is dominant, whereas red and white are recessive.

• Red is dominant.

An individual with (naturally) curly hair and an individual with (naturally) straight hair mate; all of their offspring have (naturally) wavy hair. What is the relationship between the alleles for hair texture?

• pleiotropy

• wavy hair dominant to both straight and curly hair

• codominance

• incomplete dominance

A gene that is located on a sex chromosome (X or Y chromosome) is ________.

• a linked gene

• a sex-linked gene

The sex chromosomes in humans that make an individual a male are ________.