Biology Mutations Flashcards

What are the two types of gene mutations?

What are point mutations caused by?

What type of point mutation changes one nucleotide into another?

What types of mutations do substitutions lead to? (Select all that apply)

What is an example of a missense mutation?

What happens in silent mutations?

What do nonsense mutations lead to?

What are frameshift mutations?

Are frameshift mutations almost always lethal?

___ mutations change the reading/coding of the DNA that makes RNA which may make wrong proteins.

In frameshift mutations, the mRNA is ____ as well as the protein.

What are the two types of frameshift mutations?

What is an insertion mutation?

What characterizes a deletion mutation?

What is an example of a disease resulting from a deletion?

What are the results of frameshift mutations?

Gene Mutations Overview

Two main types of gene mutations: point mutations and frameshift mutations.

Point Mutations

Result from changes in a single nucleotide base.

Substitution Mutations

A specific type of point mutation where one nucleotide is replaced with another.
May or may not alter the resulting protein.

Outcomes of Substitution Mutations

Can lead to three types of mutations: silent, missense, and nonsense.

Missense Mutations

Involve a new nucleotide creating a new codon that codes for a different amino acid, leading to the formation of a new protein.
Example: sickle cell anemia, caused by a missense mutation affecting hemoglobin.

Silent Mutations

The new nucleotide results in a new codon that still encodes the same amino acid, producing the same protein.

Nonsense Mutations

A new nucleotide leads to a premature stop codon, resulting in a shorter protein.

Frameshift Mutations

Occur due to the insertion or deletion of one or more nucleotides in the DNA sequence.
Nearly always lethal as they disrupt the reading frame of the genetic code.

Effects of Frameshift Mutations

Incorrect reading of DNA leads to misreading of mRNA and subsequent synthesis of an incorrect protein.
Results in the production of a wrong protein or an early stop in translation.

Types of Frameshift Mutations

Insertion: Adding one or more nucleotides to the sequence alters the resulting protein.
Deletion: Removing one or more nucleotides from the sequence also changes the protein.

Disease Examples from Frameshift Mutations

Cystic fibrosis is an example of a disorder caused by a deletion mutation.

Test your knowledge of different types of gene mutations with these flashcards. Learn about the distinctions between silent, nonsense, missense, and frameshift mutations through definitions and examples. Perfect for biology students looking to reinforce their understanding of genetic alterations.