Genetic Mutations
Yes I know the turtles were affected by radiation, not genes |
Genetic mutations are a permanent change to a cell's DNA sequence or chromosome. Every living thing has genetic material which controls your body's function and determines your physical features. Some things like eye or hair color are determined by genes. However sometimes the genetic code changes and mutates. Sometimes they happen spontaneously or randomly during cell division.
Most of these changes do nothing at all. They are often corrected by DNA repair, so they don't become permanent. That basically sums up what DNA repair is. It just looks over DNA and gets rid of any mutations. When mutations do become permanent however, they are usually deleterious or bad.
The cell on the left is normal and the one on the right is a sickle cell |
For example sickle cell anemia, which is a blood disease, is caused by a very small mutation in a protein-encoding gene. It turns blood cells into crescent shapes instead of circles when oxygen level in the blood drops.
Another example is Tay-sachs disease. Tay-Sachs disease is a life-threatening disease of the nervous system passed down through families.
Occasionally a mutation is beneficial and helps an organism survive. For example a bird having a longer beak would be beneficial because it could reach out farther. In fact beneficial mutations is probably why we have evolved so much. Organisms with beneficial mutations are more likely to pass their mutated genes down to their offspring. Mutations can also be caused by other forces such as chemicals, radiation and viruses. Mutations because of radiation or chemicals often are the subject of movies. Some examples are Teenage Mutant Ninja Turtles, Godzilla and most superheroes.
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