Ch. 7 Biology Clauson

A person who has a disorder caused by a recessive allele is

• considered a carrier for the disorder
• homozygous for the recessive allele
• unable to pass the allele onto offspring
• going to have children with the disorder

Human height occurs in a continuous range because it is affected by the interaction of several genes, making it a

• autosomal trait
• sex-linked trait
• polygenic trait
• codominant trait

A female is born with attached earlobes, which is a recessive phenotype. Which of the following genotypes could her parents have?

• RR x RR
• Rr x RR
• Rr x rr
• RR x rr

Suppose a mouse is homozygous for the alleles that produce black fur and homozygous for the epistatic gene that prevents fur coloration. What color fur will the mouse have

• all white
• mostly black
• entirely gray
• black and white

Some members of a family have a recessive sex-linked disorder. Which of the following statements about the family would be true

• All males would have the disorder
• All females would be carriers
• Only males would have the disorder
• Only females would be carriers

The main reason why sex-linked disorders usually only observed in males is because the Y chromosome cannot mask the alleles on the X chromosome

• True
• False

Which of the following tools is used to match up chromosome pairs using chemical stains

• pedigree chart
• karyotype
• meiosis map
• linkage map

Two parents have the genotype Gg for a genetic disoder caused by a dominant allele. What is the chance that any of their children would inherit the disorder

• 25%
• 50%
• 75%
• 100%

The genetic trait that appears in every generation is called

• dominant
• phenotypic
• recessive
• superior

How many different phenotypes can be produced by a pair of incomplete dominant alleles

• 1
• 2
• 3
• 4