> To me it seems strange not to know the gross anatomy but to be able to sequence the DNA; I can see how it could happen. They're just looking at an image of t

> To me it seems strange not to know the gross anatomy but to be able to sequence the DNA; I can see how it could happen. They're just looking at an image of the cell and seeing these unknown structures. They cannot be sure what it is. It is impossible to determine whether its DNA or not from the image. Quite independent of this, we can take a sample containing the organism and sequence its DNA without knowing where it originated from in the source cell. DNA is purified for sequencing from other cell structures by chemical and mechanical methods.