Depending on the title, there may be more or fewer duties required for the position. While smaller offices may have office assistants perform the duties of secretaries or file clerks, larger offices might have their assistants stick to one duty, such as filing.
Updated August 03, 2017. 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.
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.