3 31 Evolution

Key Points:
1. Evolution : A change in the form of organisms.
                     A change in the frequency of alleles.
2. Natural selection is the mechanism of evolution, and was proposed by Charles Darwin.
3. A chemical called Methecilline can kill Staphlococcus Aureus. The ones that can be killed are known as the succeptable. A random mutation to the genotype of Staphlococcus Aureus may cause it to be able to methecilline, and this kind of staphlococcus aureus is known as the resistant form.
4. There are now forms of the bacteria, when antibiotics are applied to the population (change in environment) then the susceptable form lowers in numbers, and the resistant ones gain numbers.
5. There are two features to be noticed: 1. Random mutation 2. Non random selection
This is known as natural selection