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.
Point mutations may arise from spontaneous mutations that occur during DNA replication. The rate of mutation may be increased by mutagens. Mutagens can be physical, such as radiation from UV rays, X-rays or extreme heat, or chemical (molecules that misplace base pairs or disrupt the helical shape of DNA).f a mutation is present in a germ cell, it can give rise to offspring that carries the mutation in all of its cells. This is the case in hereditary diseases. In particular, if there is a mutation in a DNA repair gene within a germ cell, humans carrying such germline mutations may have an increased risk of cancer.