Office Assistant Tasks. 1  Answer phones, direct calls and take messages. 2  Operate office machines; photocopiers and scanners, facsimile machines, voice mail systems and personal computers. 3  Maintain and update filing, inventory, mailing and database systems. 4  Open, sort and route incoming mail, answer correspondence and prepare outgoing mail.
DNA mutations happen when there are changes in the nucleotide sequence that makes up the strand of DNA. This can be caused by random mistakes in DNA replication or even an environmental influence like UV rays or chemicals.
1 Gene mutations that occur after birth. 2  Most gene mutations occur after you're born and aren't inherited. 3  A number of forces can cause gene mutations, such as smoking, radiation, viruses, cancer-causing chemicals (carcinogens), obesity, hormones, chronic inflammation and a lack of exercise.ancer is caused by changes (mutations) to the DNA within cells. The DNA inside a cell is packaged into a large number of individual genes, each of which contains a set of instructions telling the cell what functions to perform, as well as how to grow and divide.