Bacteriophages

by Jason Amores Sumpter
351 views
2
Was this helpful ?
2
in this video, we're going to begin our lesson on the Hershey Chase experiment. And so what's important to recall from our previous lesson videos is that even after the Griffith experiment and subsequent experiments that showed that DNA is the genetic material, many scientists still remained skeptical that DNA could be the genetic material. And they felt that proteins were actually a better candidate to be the genetic material. And it wasn't until 1952 when the scientists Alfred Hershey and Martha Chase used bacterial Fage is in order to confirm that DNA actually is the genetic material. And it wasn't until this Hershey Chase experiment that most scientists were convinced that DNA is the genetic material, not protein. And so, again, Hershey and Chase they used bacterial fage is to help them confirm that DNA was the genetic material. But what are these bacteria oaf? Ages? Well, bacteriophages are also sometimes referred to as just Fage is, and so bacteria pages and pages are the same thing, and really what they are. They are a virus that replicates itself by infecting and hijacking bacteria and so down below in our image, we're showing you, uh, a representation of what a bacteria fage actually looks like. And it's this pink structure that you see here and typically these bacteria phases they consist of an external protein coat and this external protein coat is going to be surrounding a nuke Laich acid core in the center. And so what you can see here in our images Uh, this bacterial fage that you see here consists of an external protein coat that you can see here and within this external protein coat, you can see that on the inside is the new Clague acid core. And so the new clinic acid here would represent DNA here in this scenario. And, of course, what these bacteriophages do is they in fact, bacterial cells and so you can see that are bacterial cells being shown down below? Here and now today we know that the way that bacteriophages operate is they inject the new click acid into the bacterial cell. But at the time in the 19 fifties, they were not sure exactly how these bacterial Fage is operated. Some scientists thought that perhaps it's the protein that actually makes its way into the bacterial cell on dso this her she chased experiment is the one that really revealed how the bacteria phages worked and the, um, that revelation of how bacteriophages work helped to confirm that DNA is the genetic material. But we're going to talk more about the details of the Hershey Chase experiment in our next video. For now, this concludes our introduction to the Hershey Chase experiment and how they use bacteria pages and again, I'll see you in our next video to turn toe, learn more.