Genetic Mutations

Why do most changes to DNA have NO effect at all?

• Because they're too minor to have any effect

• Because the changes are offset by RNA, which cannot change

• Because the changes are quickly repaired

• Because the changes only occur in a few cells

A mutation that decreases an organism's ability to survive and reproduce

• harmful mutation

• helpful mutation

• neutral mutation

An insertion/additon mutation occurs when

• a base pair is missing from the DNA strand

• a base pair is added to the DNA strand

• a base pair is replaced with a different base pair

A deletion mutation occurs when

• a base pair is missing from the DNA strand

• a base pair is added to the DNA strand

• a base pair is replaced with a different base pair

Which of the following is an example of a beneficial mutation?

• When an organism's lifespan becomes shorter.

• When an organism becomes unable to reproduce.

• When an organism's body becomes deformed.

• When an organism develops immunity to a disease.

The base pair guanine always pairs with which other base pair?

• thymine

• adenine

• cytosine

• guanine

A _____ is a coiled-up, condensed, or tightly wound piece of DNA

• Chromosome

• RNA

A mutation that has NO effect on an organism's ability to survive and reproduce

• harmful mutation

• helpful mutation

• neutral mutation

What usually happens to a cell whose DNA has been damaged?

• It has trouble manufacturing certain proteins

• Its genetic material leaves the nucleus

• It is able to produce twice as many proteins as a normal cell

• It shrinks to half its normal size

How are cancerous cells different from normal cells?

• Cancerous cells are shaped differently than normal cells

• Cancerous cells divide more frequently than normal cells

• Cancerous cells contain chemicals not found in normal cells

• Cancerous cells need more oxygen than normal cells