EDTA is a chelating agent used to preserve samples for DNA extraction and as an anticoagulant
Explanation:
Ethylenediaminetetraacetic acid (EDTA) is a well-known chelating agent that binds metal ions (iron and calcium ions). In police cases, EDTA can be used for DNA extraction since this agent chelates metal ions in DNase enzymes which are contained in the samples, thereby reducing their activity and preserving DNA samples for a long time. Moreover, EDTA is also used as an anticoagulant for blood cells, which allows preserving the cellular components and the morphology of blood samples.
Nucleoside analogs are the mutagenic chemicals that have a structure that is similar to the normal bases of the nucleotide and thus can be incorporated in the DNA during the process of replication, however as it has different base-pairing rules than the normal nucleotide base it can lead to mutations.
An example of a nucleoside analog is acyclovir which an analog of guanosine.
