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Missense and Frameshift mutations explained

A missense mutation is a mistake in the DNA which results in the wrong amino acid being incorporated into a protein because of change, that single DNA sequence change, results in a different amino acid codon which the ribosome recognizes. Changes in amino acid can be very important in the function of a protein. But sometimes they make no difference at all, or very little difference. Sometimes missense mutations cause amino acids to be incorporated, which make the protein more effective in doing its job. More frequently, it causes the protein to be less effective in doing its job. But this is really the grist of evolution, when missense mutations happen, and therefore small changes, frequently small changes in proteins, happen, and it happens to be that it improves the function of a protein. That will sometimes give the organism that has it a competitive advantage over its colleagues and be maintained in the population. A frameshift mutation is a particular type of mutation that involves either insertion or deletion of extra bases of DNA. Now, what's important here is the number three. The number of bases that are either added or subtracted can't be divisible by three. And that's important because the cell reads a gene in groups of three bases. Every group of three bases corresponds to one of the 20 different amino acids that are used by your body to make proteins. And keep in mind your body has a lot of proteins; everything from the material that makes up your skin, to the material that makes up your hair, to the digestive juices that help you digest that yummy lunch you just had. If a mutation disrupts one of those reading frames, so that the wrong amino acid is put in place, then the entire DNA sequence following the mutation will be disrupted or read incorrectly. Very often, what we see is a premature termination. Instead of the encoded protein being of a certain particular size, it'll end up being much shorter, and it won't be able to accomplish the role that's been set out for it. Problems: A missense mutagen cannot revert a frameshift mutation. A) True * B) False Mutations can occur in chloroplasts and mitochondria A) True * B) False