20.1 - Gene Mutations Flashcards
Gene mutations in body cells and gametes Causes of mutations Substitution mutations and their effects Other types of gene mutations
What are gene mutations?
Permanent changes in DNA sequence that make up a gene
What is the difference between mutations in body cells and gametes?
Gamete mutations inherited
What are mutagens?
External factors increasing mutation rate
What are examples of mutagens?
Ionising radiation
What is a substitution mutation?
One DNA base replaced by another
What are the possible outcomes of substitution mutations?
Stop codon
What is the effect of a stop codon mutation?
Premature termination of polypeptide synthesis
What is the effect of a different amino acid mutation?
Change in protein sequence
What is the effect of a same amino acid mutation?
No effect
What are other types of gene mutations?
Inversions
What is an inversion mutation?
DNA segment detaches
What is a duplication mutation?
DNA bases repeated
What is a translocation mutation?
DNA segment moved to another chromosome
