Mutations Flashcards
1
Q
What is a mutation?
A
‘A random change in the genetic material of an individual, the change can be large or small, beneficial to evolution or detrimental to the survival of the animal’.
2
Q
What are neutral mutations?
A
Mutations that do not have a negative or positive effect on the organism.
3
Q
What are examples of a Beneficial mutation?
A
- Colours/patterns
- Antibiotic-resistant bacteria
- Body structure
4
Q
What are examples of a Detrimental mutation?
A
- Genetic Disorders
- Cancer
- Albinism
5
Q
Explain the two categories of mutations.
A
- Spontaneous; These occur naturally, they are not frequent and are often unpredictable.
- Induced; Altercations in the gene after it has come in contact with mutagens and environmental causes e.g. chemicals, or radiation.
6
Q
What are the types of mutations?
A
- Point/Substitution - One base pair swapped for another.
~ Silent - the change occurs in non-coding regions of DNA so it does not affect the phenotype.
~ Missense - the codon now codes for a different amino acid.
~ Nonsense - The change codes for a stop codon resulting in an incomplete protein. - insertion - Extra base pairs are inserted into the DNA sequence.
- Deletion - Base pairs are lost from the DNA.
- Duplication - Sections of DNA are repeated.
- Translocation - Sections of DNA either swap places or chromosomes join together.
7
Q
What are Frameshift mutations?
A
- They can alter the point from where a codon is read.
- It completely changes the amino acid sequences.
- This type of mutation may result in phenotypic changes.