B5.1.7 - Mutations Flashcards
When does a mutation occur?
When the sequence of DNA bases is altered spontaneously
Give an example of how DNA bases alter in sequence?
The DNA may not replicate properly
Name substance that can increase the chances of a mutation occurring.
Benzene
Ethanol
Radiation (UV)
What is a genetic variant?
A different version of an allele which arises from mutations
What determines whether a mutation will have an effect on your phenotype?
The position of the mutation in the DNA sequence
How often will a mutation determine an organism’s phenotype?
Not very often
How many mutations are harmful?
Most
Give examples of how mutations can be harmful
They can cause cancer
Cause the production of abnormal protein cells
Cause different shaped protein molecules to be formed
What is cancer?
An illness where cells grow and divide uncontrollably
What are protein channels?
Channels that allow molecules to be transported through the cell membrane
Give an example of a differently shaped protein molecule
People with sickle cell anaemia have unusually shaped haemoglobin molecules, making their blood cells sickle shaped
Give an example of a gene mutation which is neutral
Rolling your tongue
Give an example of a beneficial mutation
Some mutations in bacteria make them resistant to antibiotics
