Unit 5 Reflection

Unit 5 Reflection/ Notes

Unit 5 was the unit based off of… mutations. Problems with DNA, sometimes good, sometimes harmless, and sometimes detrimental. This unit went over point mutations, frameshift mutations, inversions, and translocations.

Point mutations are changes in one or two base pairs of DNA, and are small but common. These can be harmful if the protein changes a lot, but if the protein doesn’t really change they’re harmless. There are two main types of point mutations; substitution and frameshift mutations. In substitution, a nucleotide is substituted for another(ex. T is replaced by A by mistake). Frameshift mutations occur when a, insertion, where an extra base pair is added into the code, or b, deletion, where a base pair is left out of the code.

Some other mutations include inversion, where a piece of DNA breaks off and bonds in reverse order. Translation occurs when part of a chromosome breaks off and bonds with another chromosome.

Why do mutations matter to us though? First off, changes in DNA means changes in proteins, and some diseases are caused by the smallest of things, even a change of a single base. Mutations can be detrimental like said earlier, resulting in cancers or life threatening problems. Mutations can be very useful too. They could accidentally create new genetic variation for natural selection, causing resistances to certain things in nature.

Gene regulation is the reason why we don’t sprout hair on our eyes and ears on our chest. Cells don’t want to perform more than the necessary actions for the cell to function, so there is something called an operator that prevents the RNA polymerase from reading the gene. This is necessary, because without the operator the RNA polymerase would read the gene and keep making excess amounts of whatever results from the initiated process.