Endocytosis and Exocytosis

in this video, we're going to begin our lesson on Endo Psychosis and Exocet Asus. And so up until this point, in our course, we've been talking about the membrane transport. A very, very small molecules. But what about large molecules? How do they get across the cells? Plasma membrane. Well, large biomolecules, for example. Large proteins, large carbohydrates or nucleic acids like DNA there simply just way too large in order to diffuse through membranes or even to diffuse through protein channels. And so they're not able to defuse through the methods that we've talked about so far. And so instead, large macro molecules are going to be transported across cell membranes via either the process of endo psychosis and or the process of Exocet Assis. And we'll get to talk a lot. Maura, about Endo Psychosis and Exocet Acis as we move forward in our course, but down below here we're showing you a map. Ah, little snippet of our map of the lesson on membrane transport and notice that we're focusing on bulk transport or the transport a very, very large molecules. And these large molecules can either be transported via endo psychosis to enter the cell and or Exocet Asus to exit the cell. And so we're going to start off our lesson by focusing on Endo psychosis entering the cell. And really, there are three types of endo psychosis that were briefly going to touch on which ARF ago psychosis sell eating Pena psychosis, sell drinking and then receptor mediated Endo psychosis, which is a form of pinot psychosis. And then later, after we talk about Endo psychosis, we'll talk about Exocet Asus exiting the cell. But for now, this year concludes our introduction to end a psychosis and exercise. It assists, and we'll get to learn more about these processes as we move forward in our course, so I'll see you all in our next video.

in this video, we're going to focus on Endo site Asus and how Endo Psychosis allows entry into the cell. And so the e n and Endo site Assis is going to be very helpful to remind you about what it does. And that's because Endo site Assis is defined as macro molecule engulf mint by the cell membrane, allowing for entry into the salvia, a lipid vesicles. And so you can see the e n and Endo Psychosis is for the e n and engulf mint and the E n and entry. And so the big idea here is that molecules are going to be brought into the cell with endo psychosis. Now, really, there are three main types of endo psychosis that you all should know. The first type is fag. Oh, site assis. Now, if ago site assis is when a large solid material is being taken into the Sylvia and a psychosis, and because it is a solid material, it's commonly known as sell eating. Now, the second type of Endo site Asus that you all should know is pinot site Assis and Pino site Assis is defined as when a small liquid material is being taken into the sell by Endo psychosis. And because the materials are liquid, uh, it's commonly known as sell drinking. And then the third and final type of endo psychosis that you all should know is receptor mediated, endo psychosis and really receptor mediated. Endo psychosis is just a special form of pinot psychosis, and that's why we have this little indentation here to show that hey receptor mediated of psychosis. It's just a special type of Pino psychosis, and it says here it's a specific form of Pena psychosis that uses receptor proteins. So let's take a look at our image down below to get a better understanding of these ideas. So on the far left over here, notice that we're showing you the first type of endo psychosis fa go psychosis, and so notice that the outside of the cell is over here and the inside of the cell is over here and notice that a bacterium is being brought into the cell here, and when it's brought into the cell, it ends up inside of a lipid vesicles and recall vesicles are just these little membrane bubbles on it. It will bring in thes large, solid materials such as the bacteria here. Now, moving on Pino Psychosis is over here in the middle and notice that it is three outside is over here and the inside of the cells over here. And so these small liquid materials are being brought into the salvia, a lipid vesicles. And so this is pinot psychosis or cellular drinking. Now, the final type of endo psychosis that you all should know is receptor mediated endo psychosis, which is really just a form of pinot psychosis. So cellular drinking, so you can see the same blue molecules being brought in as pinot psychosis. But the real difference is that receptor mediated endo psychosis uses these orange receptors that you can see embedded in the membrane at these positions here. And so the receptors are proteins that have ah specific binding attraction to these blue liquid molecules. And then, of course, because it's a form of endo psychosis, it's going to be brought into the cell and a lipid vesicles. And so the big idea here is that receptor mediated Indo psychosis uses thes receptors, these orange receptors. And so this year concludes our introduction to end a site, Asus and how Endo psychosis. The E N is going to remind you that it allows for entry into the cell, and so we'll be able to talk about exo psychosis in our next video, so I'll see you all there.

All right. So here we have an example problem that says white blood cells of our immune systems engulf bacteria using which type of endo psychosis, and we've got these four potential answer options down below. Now, after reading through these options, we know from our last lesson video that faggot psychosis and pinot psychosis are definitely types of endo psychosis that we talked about in our last lesson video. But as Moses is definitely not one of the types of Endo site Assis. And also, when we look at option D, it says receptor mediated Exocet tose is but receptor mediated XO site Assis is not a type of Endo site Asus and so receptor mediated endo site Asus would be a type of endo psychosis. But receptor media XO psychosis is not. And so we did not talk about that in our last lesson video so we can eliminate option to see an option D. So now we're between either option A or Option B and so, uh, notice. It's saying white blood cells of our immune systems in golf bacteria and bacteria is going to be a solid. And because bacteria is a solid, it's going to be involved with cellular eating. And if it were a liquid, then it would be involved with cellular drinking and recall from our last lesson video that it's fa go sight. Oh sis, that is involved with cellular eating, eating essentially solid materials like bacteria. And so Pena site Assis is involved with cellular drinking. But again, bacteria are not liquids there solids. And so Option B is not going to be correct. An option A is the correct answer to this example. Problems. So that concludes this example, and I'll see you all in our next video.

So in our last lesson video, we talked about Endo psychosis and how it allows for entry into the cell. And so in this video, we're going to talk about the complete opposite of Endo Psychosis, which is XO site ASUs and how Exocet ASUs allows exiting from the cell. And so the e X and X o psychosis is going to be very helpful for you all toe. Remember exactly what Exocet Assis is about, and so Exocet assis can be defined as vesicles fusion with the cell membrane, allowing the contents of the vesicles to exit the cell into the extra cellular space or the outside space outside of a cell. And so you can think the E X and Exocet Assis is for the e X and exit and the E X and extra cellular space. Now there are many, many different types of molecules that can undergo Exocet ASUs, but a few examples include hormones, nure oh, transmitters and digestive enzymes. And this is just a small subset of all of the examples of molecules that can undergo Exocet ASUs allowing exiting from the cell. So let's take a look at our image down below to get a better understanding of this and notice the inside of the cells over here on the right hand side. And the outside of the cell is over here on the left hand side. And so notice that originally these red molecules that you see here that are representing hormones are inside of a vessel inside of a membrane bubble. Here on the inside of a cell and this membrane bubble, this vessel ical can start to fuse with the cells plasma membrane here. And when that vesicles fully fuses, it can release the contents that used to be on the inside of the vesicles. And so ultimately, what we get is the vesicles contents are being released into the outside of the cell. And so these contents are exiting the cell via XO psychosis. And so this year concludes our introduction to Exocet ASUs and how it allows exiting from the cell. And we'll be able to get some practice applying these concepts as we move forward in our course. So I'll see you all in our next video