Biology Chapter 13.3: Mutations Flashcards

Substitution: A change of one base to another in a DNA sequence.
Point Mutation: A change occurring at a single point in the DNA sequence, affecting one or a few nucleotides.

Translocation: Occurs when part of one chromosome breaks off and attaches to another chromosome.
Mutation: A heritable change in genetic information that can occur through various mechanisms.
Duplication: A mutation resulting in an extra copy of all or part of a chromosome.
Inversion: A chromosomal mutation that reverses the direction of parts of a chromosome.
Frameshift Mutation: A mutation that alters every amino acid following the point of mutation, typically caused by insertions or deletions.
Insertion: The addition of a base to the DNA sequence, resulting in a potential frameshift.
Deletion: Can occur as a gene mutation (removing a base from the DNA) or a chromosomal mutation (losing part/all of a chromosome).

DNA replication machinery inserts an incorrect base roughly once in every 10 million bases.
Small genetic changes accumulate over time, influencing evolution.
Mutagens, such as ultraviolet light, can cause changes in DNA sequences.
If cells cannot repair mutagen-induced damage, the DNA base sequence changes permanently.

Most mutations have little to no effect, while some can be harmful or beneficial, impacting fitness.
Mutations are a source of genetic variability, crucial for the evolution of species.
Cancer results from mutations that enable uncontrolled cell growth.
Polyploidy: Condition where an organism has an extra set of chromosomes, often observed in plants.

Sickle cell disease is caused by a substitution mutation in the hemoglobin gene located on chromosome 11.
A single base-pair change leads to the incorrect incorporation of valine instead of glutamic acid in hemoglobin.
This alteration affects the protein's structure and function, resulting in serious health consequences like sickle-shaped blood cells.

Ensure to review handouts for detailed visual information on blood cell differences and specific mutation processes.

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