In biology, a mutation is a permanent change of the nucleotide sequence of the genome of an organism, virus, or extrachromosomal DNA or other genetic elements.
Salinity is the saltiness or dissolved salt content of a body of water (see also soil salinity).onceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sodium bicarbonate which dissolve into ions.
Salinity in the ocean is defined as the grams of salt per 1000 grams of water. One gram of salt per 1000 grams of water is defined as one practical salinity unit or one PSU.