Mutations Flashcards
What are mutations?
permanent changes to the genetic information of an organism by altering the nucleotide sequence of their (DNA)
What is a mutagen?
An environmental agent that causes a genetic mutation
DNA is transcribed to form…
mRNA
mRNA is then translated into a…
polypeptide
How can changing DNA alter the cell structure and function of a cell?
Changing DNA involves changing a sequence of nucleotide bases.
Changing a sequence of nucleotide bases in DNA → changes the template for the mRNA→ in transcription, the strand of mRNA will be composed of a different complementary sequence of nucleotide bases → in translation, the mRNA will code for a different set of codons → creates a different polypeptide → polypeptides will form a different enzyme/protein, which could potentially be dysfunctional → dysfunctional enzymes/proteins cannot fulfil their role in a cell → a problem as proteins are essential to the structure, function and regulation of the body as they are used to build and repair muscles and bones, as a source of energy, to make hormones and enzymes, etc
What are variations?
the differences in genes between individuals
What are the two main factors that determine what the variation will be between individuals?
genetics and the environment
What can mutations do for the gene pool of a population?
they can introduce new alleles to the population
What are two ways a mutation can occur?
1) by a spontaneous, uncorrected mistake made int the process of DNA replication
2) environmental factors
What are some environmental factors that can cause mutations?
1) exposure to UV light
20 cigarette smoke
What is the risk of altering DNA?
altering DNA changes the information coded in the gene, which may alter the protein or RNA end-product
variation in genes caused by mutations are called…
alleles of the gene
What is the significance of some genes having markers in medical research?
Some genes have markers that may
be associated with mutations, and these markers can potentially be used to identify health problems
What are three (real-life, actual events and people) examples of mutations caused by radiation?
1) Marie Curie, worked with ionising radiation and died of leukaemia caused by radiation exposure
2) Rosalind Frank, who worked with X-rays, died of ovarian cancer from radiation exposure
3) Survivors of the 1945 Hiroshima bombing suffered physical mutations from radioactive exposed from the nuclear explosion
What can radiation (and other certain chemicals) do to genes?
they can change the structure of DNA and lead to cancer
