DNA Mutations — Unit test Answers

Based on scientific research, which statement best describes mutations?

A scientist thinks that a certain chemical is a mutagen. She exposes plant cells to a large amount of this chemical in the laboratory. Which statement best provides evidence that the substance is a mutagen?

Which type of mutation always produces a stop codon?

Which is considered a chemical mutagen?

Which statement is scientifically based?

Ji wants to write an example of a frameshift mutation using the following sentence: THE CAT SAW THE RAT. Which sentence best shows a frameshift mutation?

Which best describes somatic mutations?

Many different types of mutations can occur within the body. Sickle cell anemia is a disease that occurs when a mutation in a base pair of the hemoglobin beta gene causes a single replacement of the amino acid glutamic acid by the amino acid valine. As a result of this mutation, the individual’s blood cells take on a sickle shape under certain conditions and form clusters that can block blood vessels and cause organ damage. Which type of mutation causes sickle cell anemia?

A point mutation changes the DNA sequence CGA to CGT, but the same protein is still produced. Which point mutation occurred?

Many different types of mutations can occur within the body. Tay-Sachs disease is a deadly disorder that is caused by a missing codon in the gene coding for production of the hex A enzyme in the body. Which type of mutation is responsible for causing Tay-Sachs disease?