- Evolution:
1. change in the form of organisms
2. Chang in the frequency (how many) of alleles
- Natural Selection is the mechanism of evolution and was first proposed by Charles Darwin.
- Example: skin infections by the bacteria staphlococcus aureus.
- Methecilline is a type of antibiotic that kills staphlococcus aureus. The staphlococcus areus that can be killed by this antibiotic are described as the susceptible forms.
- What occurs: a random mutation to the genome which allowed it to develop the characteristic of breaking down methecilline. It therefore, no longer killed by the antibiotic and are described as the resistant form.
- 2 form of the bacteria = evolution.
- When antibiotics are applied to the MSSA population, it decreased
- because MRSA is resistance, they becoming increasingly common = evolution
Features:
1. Random mutation - MRSA form
2. Non-random selection - Antibiotic selecting the MRSA to survive and MSSA to be selected and killed.
- The two components are classic features of Natural Selection.
- Natural selection is a process and not a thing.
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