Mutations_Flashcards
What are mutations?
Alterations in the genetic information within DNA or RNA sequences.
What are the two dynamic classifications of mutations?
Dynamic (linked to mutation copy number) and static.
How are mutations classified by size?
As point mutations or chromosomal mutations.
What do point mutations affect?
A small number of nucleotides within a single gene.
What do chromosomal mutations affect?
A larger number of nucleotides and can involve loss or gain of chromosomes (e.g., trisomy, monosomy).
What are the two main causes of mutations?
Spontaneous mutations and induced mutations.
What causes spontaneous mutations?
Uncorrected errors during DNA replication or mistakes by DNA repair systems.
Why is the frequency of spontaneous mutations typically low?
Due to efficient DNA repair enzymes.
What are induced mutations caused by?
Exposure to mutagens.
Name examples of mutagens.
Ionizing radiation (X-rays, UV radiation) and some viruses.
How does mutation location affect its impact?
It depends on whether the mutation occurs in coding, regulatory, splicing, or polyadenylation sequences.
What are potential effects of mutations?
Prevent protein production, alter protein expression levels, or alter protein function.
What determines the phenotypic outcome of a mutation?
The mutation’s position within the DNA sequence.
What are germ cell mutations?
Mutations in germ cells (sperm or egg) that are hereditary and passed to offspring.
Do germ cell mutations affect the individual carrying them?
No, they do not.
