Practice: AP Biology mutations and effects

What is a mutation?

A change in the DNA sequence that can affect gene function.

Types of mutations

1. Point mutations 2. Insertions 3. Deletions 4. Duplication 5. Inversions

Fill in the blank: A _____ mutation changes one base pair.

point

True or false: Mutations can be beneficial, neutral, or harmful.

True, because they can alter protein function.

Difference between missense and nonsense mutations

Missense mutations change one amino acid; nonsense mutations create a stop codon.

What is a frameshift mutation?

An insertion or deletion that alters the reading frame of the genetic code.

Question: What can cause mutations?

1. Environmental factors 2. Radiation 3. Chemical exposure 4. Replication errors

True or false: All mutations are inherited.

False, because only germline mutations can be passed to offspring.

Example of a disease caused by mutation

Sickle cell anemia, caused by a point mutation in the hemoglobin gene.

What is a silent mutation?

A mutation that does not change the amino acid sequence due to redundancy in the genetic code.

Fill in the blank: Mutations that occur in body cells are called _____ mutations.

somatic

What is a duplication mutation?

A type of mutation where a segment of DNA is copied, resulting in multiple occurrences.

True or false: Mutations are always harmful.

False, because some mutations can provide advantages.

Comparison: Substitution vs. frameshift mutations

Substitution changes one base pair; frameshift alters the entire reading frame.

What is a regulatory mutation?

Mutations affecting gene expression rather than protein coding.

Question: What role does natural selection play in mutations?

It favors beneficial mutations, while harmful mutations may be eliminated.

True or false: Environmental factors can influence mutation rates.

True, as certain chemicals and radiation increase mutation risks.

Example of a spontaneous mutation

A replication error that occurs during DNA synthesis.

What is a chromosomal mutation?

A mutation that involves changes to the structure of chromosomes.

Difference between germline and somatic mutations

Germline mutations are inherited; somatic mutations are not.

Fill in the blank: The change in phenotype due to a mutation is known as _____ effect.

phenotypic

True or false: All mutations lead to a change in phenotype.

False, as silent mutations do not affect the phenotype.

What is an induced mutation?

A mutation caused by external factors like chemicals or radiation.

Fill in the blank: A mutation that results in a premature stop codon is a _____ mutation.

nonsense

Question: How can mutations lead to cancer?

Mutations can disrupt cell cycle regulation leading to uncontrolled cell growth.