Ch.15 Practice Questions

The scientist who used x-ray diffraction photography to develop an understanding of the molecular structures of DNA

• Gregor Mendel

• Rosalind Franklin

• Francis Crick

• Robert Weinberg

Which term is used to consider the normal, common phenotype?

• wild type

• mutant

• recessive

• linked gene

Why do linked genes typically get inherited together?

• because they are on opposite chromosomes

• because its they are sister chromosomes

• because they separate independently

• because they are on the same chromosome

What process sometimes break the physical connection between genes on the same chromosome?

• independent assortment

• crossing over

• incomplete dominance

• random fertilization

Why are males more likely to be colorblind than females?

• Colorblindness is a Y-linked trait

• Colorblindness is an X-linked trait

• Colorblindness is a dominant trait

• Males are not more likely to be colorblind

Which is less likely to occur in humans?

• Aneuploidy

• Polyploidy

Which of the following examples of alternation of chromosome structure depicts duplication?

• ABCD -> ABABCD

• ABCD -> ACBD

• ABCD -> ABC

• ABC & DEF -> ABF & DEC

What is down syndrome?

• polyploidy condition

• 2 copies of chromosome 21

• 3 copies of chromosome 21

• Tetrasomy 21

Red-green color blindness is a sex-linked recessive trait in humans. Two people with normal color vision have a color-blind son. What are the genotypes of the parents?

• XcXc and XCY

• XCXC and XcY

• XCXC and XCY

• XCXc and XCY

During which phase is nondisjunction more detrimental?

• Meiosis I

• Meiosis II

• Mitosis

• Cytokinesis