Prokaryotic Cell Structures 2

by Jason Amores Sumpter
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some pro carry attic cells will actually have a new, additional outer coating called a capsule. Or sometimes it's referred to as the slime layer. I kind of love that name, to be honest. And this is a large Polly Sacha ride, uh, coding that will surround the cells. And it's It's basically a protective layer for the cell, right? Just another protective layer for that cell. Now some cells can form what are called endo spores, and these are, um, super resilient but dormant forms of bacteria. And they basically form in response thio either a lack of nutrients in the environment or some form of really harsh conditions. For example, some bacteria will, you know, form thes endo spores in response to you high heat or something like that. So the idea is when Thebes Bacteria realizes that it is compromised, right? It's going to die. There's not enough resource is the environment is getting super inhospitable. It will form this dormant endo spore so that it can, uh, you know, lay low, basically like hibernate almost for super long periods of time. And seriously, you know, we're talking like hundreds. Even thousands, uh, debated Lee even longer uh, periods of time before they will reactivate. And you can see just a bunch of examples of endo sports here. Three idea being that they come in all shapes and sizes. Uh, I don't really need to know anything specific about any of these and a sports. So just another defense mechanism that some bacteria have evolved in order. Thio avoid dying in harsh conditions. Now, last thing I want Thio talk about is how pro carry outs move around. And also what appendages thes cells you. So, um, some pro Kerasiotes have what are called Fibria, and and these kind of like to think of them as little arms because they're basically appendages that allow bacterial cells thio adhere to surfaces and you can see these little pink strands on this Sell those air Fibria and those are allowing the cell to adhere to the surface that it is attached to. Now, bacteria will also have what are called flow Gela for plural or flagellum singular. So you can see that this cell has a number of flu, Gela right, pointing them out with these red arrows. And these are kind of like kind of like whips in the way they move. You can see in this image here that basically they will kind of spin around. And essentially, they're used for locomotion and sensation so they can be used for the bacteria to actually move around. And, you know, if you think about it, it's kind of crazy. But, you know, these cells air so small that essentially the flu Gellar almost like boring through the medium, you know, like water, for example, essentially like boring through the water. So I like to think of them is like a Drehle or something. Almost, um, And again, you know, that just has to do with the comparative size of the bacteria to the force. The attractive forces of those molecules Now, interestingly, flagellum can also or flu Gela Rather could be also used for sensation. Um, so there are some that have evolved and been modified as a sensory appendages. Now the last type of penda I want to talk about is the Hillis. Sometimes it's called the Sex Pillows. And, um, this is a new appendage on the surface of many bacterial cells, and it's, uh, involved in this process called conjugation, that we're going to talk about Maurin depth when we discuss bacterial reproduction. But the basic idea is that this is sort of like a a tube through which bacteria can pass DNA. And again, we'll talk more about this concept later. But as you can see right here, this little bacterial cell in the diagram has this little appendage, the pillows and through this pillows that's going thio, move some of the DNA in this plasma. All right with that, let's actually turn the page.