User:Yuval Langer/he bacteriophage

בקטריופאג' זהו ווירוס התוקף בקטריה. בדרך כלל משתמשים בקיצור של המונח: פאג'. הבקטריופאג' כחלק מהביולוגיה נודע רק בתקופה המודרנית, פחות מלפני מאה שנה. The germ theory of disease, itself, has been a concept only since the 19th century, and brought such a novel understanding of how infectious diseases are spread that Medicine experienced revolutionary advances with its acceptance. המסקנה המפתיעה שגם לבקטריות יש ווירוסים הגיעה רק לאחר שהשתמשו בטכניקות ששומשו לגילוי ווירוסים שהתפתחו בראשית המאה ה-20 כדי לחקור תופעות מסקרנות הקשורות במחלות הארבה, תרביות בקטריות ומיימיו הקדושים של הנהר גנגס The suprising conclusion that germs themselves can also have germs only came after techniques used in the discovery of viruses in the early 20th century were also used to study some puzzling observations concerning the ailments of locusts, the culture of bacteria, and the sacred waters of the river Ganges.

As it turns out, bacteria are often infected with viruses called bacteriophages, and play "host" to them just as the bodies of human beings, plants, and other animals host infections of both bacteria and viruses. Phages are ubiquitous and can be found in all habitats populated by the bacterial cells that these viruses need to enter in order to be able to reproduce. Those habitats are incredibly diverse, and include the soil, the intestines of animals, and the sea. Scientists look to these habitats to find phages for study. One of the richest natural sources is sea water, where up to 107 phages per ml (or, at least, virus-like particles)[1] can be found. Whitman et al. argue that there are between 1030 and 1031 prokaryotic cells on our planet.[2] If we assume that there is one virus for every prokaryote cell (and bear in mind most bacterial cells tested are found to harbor latent phage (prophage)), then we conservatively reach a total population of 1030 to 1032 of these virus-like particles in the world.[3]