- Evolution : change in the form of organisms or change in the frequency (how many) of alleles
- Natural selection is the mechanism of evolution - Charles Darwin
- S.A.- causes infections of the lung and skin infections
- Evolving S.A.
the normal form of S.A is suceetable to being killed my methecilline (Anti-biotic)
- represented in first graph - MSSA
- random mutation to the geno of S.A - characteristic of 'breaking down methecilline' - no longer killed by the anti-biotic - resistant form
- represented in second graph - MRSA
- 2 forms of the bacteria - different forms is definiton of evolution
- when antibiotics applied to the population, MSSA is decreased and MRSA is increased (common)
- increase in the frequency of the allele for resistance (evolution)
2 features:
- Random mutation - MRSA
- non-random selection - antibiotic - MRSA to survive and MSSA to be selected and killed
- These are Natural selection - a process and not a thing
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