Answer: A substitution is a mutation that exchanges one base for another (i.e., a change in a single "chemical letter" such as switching an A to a G). Such a substitution could: change a codon to one that encodes a different amino acid and cause a small change in the protein produced.
Explanation: I know this is correct just trust me and please mark me as brainiest.
Answer:
Balanced equation have equal number of atoms of different elements in the side of reactants and products.
Darwin observed the beaks of the birds and how the different beaks helped the birds to eat different types of seeds.
This relates to natural selection because certain finches with say a smaller shorter beak would be able to eat only smaller seeds and fruits as to where a finch with a longer larger beak could eat larger bigger seeds and fruits.
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