Video Transcript: Prokaryotes and Eukaryotes

Prokaryotes and Eukaryotes

Today we're going to talk about the two different types of cells. This is a very important biology objective. But it's also really important in daily life. So let me give you an example. Let's say you get a really bad infection. And there's a lot of things that can cause infections, right? For example, bacteria can cause infections, and viruses can cause infections. But the kind of infection I'm talking about today, it's a fungus infection, fungi, and that's the plural of fungus. You don't say funguses. You say fungi. fungi can cause all kinds of infections. For example, ringworm, that's not a worm at all, despite the name, it's actually a fungus, or Athlete's Foot, that's a fungus, or yeast infection can probably really grosses you out. But this is all type of fungus infection. But the kind of fungus infection I'm going to talk about is one that's more rare. It's one that would happen if, for example, you were in the hospital and your immune system was really compromised. This is not a common thing at all. But it is possible thing, fungi can get into the bloodstream. And if it does, it is extremely difficult to treat. Why?

Well, for one thing, antibiotics do not work on fungi. Antibiotics only work on bacteria; bacteria are an example of prokaryotic cells. So fungi, it's not a type of prokaryotes, it's actually the other type of cell, called eukaryotes. And antibiotics are not effective against eukaryotes. Your own cells are also eukaryotes. So when you try to treat the fungus that's in the blood, it's extremely difficult to treat, because you might hurt your own cells, or at least have some really undesirable side effects. So the example here talked about two different kinds of cells, prokaryotes, and eukaryotes. Prokaryotes were the bacteria. Eukaryotes, however, in our example, included the fungi cells, and also the human cells.

Now, these two different cell types have one major thing in common, they both have a cell membrane, all living cells have cell membranes, we have a longer clip on how important the cell membrane is, it controls what goes in and out of the cell. And by doing that, it keeps everything pretty stable. Don't get the cell membrane, though, mixed up with a cell wall, which offers support and protection; that varies in the group. So that's not an always thing. But cell membrane. Yes, always.

Also, both prokaryotes and eukaryotes have genetic material in the form of DNA, they both have this, otherwise whenever you make more of that type of cell, there would be no way to transmit the genetic information. Prokaryotes and eukaryotes both have ribosomes, which are these tiny little structures that help make protein for the cell, we actually get to this fascinating process a little bit later. Now, one major difference though, between prokaryotes and eukaryotes is that eukaryotes have something called membrane bound organelles. I like to think of the word organelle, like the word organ, you know how you have organs in your body, you have a heart, liver, lungs, well, organelle, I'd like to think of that as kind of like little organs. And eukaryotes have these membrane bound organelles, there's a whole list of them. And if you look online, you can find a bunch of them and their functions for the cells. But prokaryotes do not have membrane bound organelles. So one way I like to tell students to remember this, you carry out the you rhymes with do they do have membrane bound organelles, and pro carry out the pro rhymes with no, and they do not have membrane bound organelles.

So what is an example of a membrane bound organelles? A very famous one is the nucleus. And I say it's famous because everyone always thinks of this one. It's kind of like the brain of the cell, it controls a lot of the cells functions. And it also holds the genetic material for eukaryotes. So the nucleus holds the DNA. Prokaryotes, again, do not have a membrane bound organelles, they do not have a nucleus. And so their DNA is organized in a different manner. And it's not as nicely organized either, as it is in the eukaryotes. We're not going to go into the different types of organelles today. That's pretty easy information to find. One thing though, that I'd like to mention the cell has a certain function, it might have more of a certain kind of organelle. Or it might have a different kind of organelle than another cell. So let me give you an example of what I'm talking about. Plant cells, for example, it's a type of eukaryotes, plant cells, you know, they make sugar from the sun. They have an organelle called a chloroplast that animal cells don't have because animal cells cannot make sugar from the sun. Or say we're talking about muscle cells in your body, they need a lot of energy in order to do their function. So actually, muscle cells have a lot of a type of organelle called mitochondria than some of your other human cells, because they have to produce so much energy. So the types of organelles and the quantity of them can vary slightly, because you've got these different cell functions. Well, that's it for the amoeba sisters, and we remind you to stay curious