Which trait is controlled by a gene with multiple alleles? a. Blood type b. Straight hairline c. Smile dimples d. widow’s peak

A. Blood type

What are multiple alleles? a. More than 2 genes for a trait b. Three or more chromosomes that determine a trait c. 2 codominant genes d. 3 or more forms of a gene that code for a single trait

D. 3 or more forms of a gene that code for a single trait

Why does height in humans have such a wide variety of phenotypes? A. Controlled by a recessive allele b. Has only 2 alleles c. Controlled by sex-linked genes d. Controlled by at least 4 genes

D. Controlled by at least 4 genes

What controls variations in skin color among humans? a. Multiple alleles b. A person’s diet c. Two alleles of a single gene d. At least 3 genes

D. At least 3 genes

What human trait is altered by variations in the environment? Smile dimples Blood type c. Height d. Skin color

c. Height

What is a pedigree? A. Chart tracking family members that have a certain trait b. Picture of chromosomes c. Geneticist studying traits d. Allele passed from parent to offspring

A. Chart tracking family members that have a certain trait

Genetic disorders are caused by a. Dominant alleles b. Pedigrees c. sickle-shaped cells d. mutations

d. mutations

Down Syndrome occurs when A. A person inherits a recessive allele b. Sickle-shaped cells get stuck in blood vessels c.chromosomes fail to separate properly d. blood does not clot properly

c.chromosomes fail to separate properly

Why are sex-linked traits more common in males than females? a.All alleles on the X are dominant b. All alleles on the Y are recessive c. A recessive on the X produces the trait in a male d. The X and Y are codominant

c. A recessive on the X produces the trait in a male

What is a karyotype? A.blood from a new born baby b. Fluid surrounding an unborn baby c. Picture of chromosomes in a cell d. Picture of a baby before it is born

c. Picture of chromosomes in a cell

Cloning results in organisms that are a. Genetically similar b. Produced from cuttings c. Both adult mammals d. Genetically identical

d. Genetically identical

No two people have the same DNA except for Brothers Sisters Identical twins d. Crime suspects

c. Identical twins

Which form of selective breeding crosses genetically different individuals in an attempt to keep the best traits of both parents? Hybridization inbreeding Cloning Genetic engineering

Hybridization

What is a genome? All the plasmids from splicing DNA in a cell All the DNA in one cell of an organism All the karyotypes in a cell All the cells produced during meiosis

b.All the DNA in one cell of an organism