The Eustachian tube is used to equalize air pressure between the middle ear and the surrounding area, but it is also used to drain mucus from the middle ear. Keeping the pressure in a person's head equalized helps with balance and preventing dizziness.
Mutations can also be caused by environmental foes. Tobacco, ultraviolet light and other chemicals are all potential enemies of DNA. One way these hazards attack our genes is very sneaky: They have the ability to damage the chemicals making up DNA.
In this kind of mutations, DNA molecule divides even before the cell division starts. Types of Mutations:- Point Mutations:- Point mutations occur when a single nucleotide is replaced with another nucleotide base.Insertion and deletion come in this category. Error in the process of replication of DNA molecule results in point mutations.rameshift Mutations:- Mispairing of the DNA molecule causes the frameshift mutations. The changes in the single base pair nucleotide sequence usually insertion or deletion result in these mutations. The whole information coded in the amino acid changes due to frameshift mutations.