Posts: 1,252. Wales has the most castles per square miles; with the UK in general having many impressive structures, and interesting clan tales, if you're in the Scottish highlands. Also, Germany and Austria cannot be underestimated in this regard either, as Neuschwanstein is legendary.
The Mimivirus, a virus infecting Acanthamoeba polyphaga, was the largest DNA virus yet isolated (Claverie et al, 2006).
Introduction to retroviruses. The family of Retroviruses are characterized by their ability to incorporate viral DNA into a host cell's genome. Most retroviruses like Rous sarcoma virus (RSV), infect dividing cells during mitosis, when the chromatin is exposed to the cytoplasm. Conversely, the genus of Lentiviruses, like the human immunodeficiency virus (HIV), have evolved in order to infect non-dividing cells.