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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 an
infection right? For example, bacteria can cause infections. And viruses can cause infections.
But the kind of infection that I'm talking about today is a fungus infection. Fungi (that's
the plural of fungus as you don't say "funguses," you say "fungi") can cause all kinds of infections.
For example, ringworm. That's not a worm at all despite its name. It's actually a fungus.
Or athlete's foot. That's a fungus. Or a yeast infection. Ok, I'm probably really grossing
you out but these are all types of fungus infections. But the kind of fungus infection
that I'm going to talk about is kind of more rare. It 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 a 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 prokaryote cells.
So fungi are not a type of prokaryote. They are 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 have some 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 things pretty stable. Don't get the cell membrane though
mixed up with the cell wall, which offers support and protection. That varies in the
group so that's not an always thing. Cell membrane? Yes, always. Also both prokaryotes
and eukaryotes have genetic material in the form of DNA. They both have this or otherwise
when you make more of this type of cell, there would be no way to transfer the genetic information.
Prokaryotes and eukaryotes both have ribosomes which are these tiny little structures that
make protein for the cell. We actually get in this fascinating process a bit later. Now
one major difference between prokaryotes and eukaryotes is that eukaryotes have something
called membrane bound organelles. I like to thing of the word "organelle" like the word
"organ." You know how you have organs in your body? You have a heart, a liver, and lungs?
Well with the word organelle, like to thing of "little organs" and eukaryotes have these
membrane bound organelles. There's a whole list of them and if you look online you can
find them, but prokaryotes do not have membrane bound organelles. So one way I like to tell
students to remember this is that in the word eukaryote, the "eu" rhymes with "do" and they
do have membrane bound organelles. The "pro" in prokaryote rhymes with "no" and they do
not have membrane bound organelles. So what is an example of a membrane bound organelle?
A very famous one is the nucleus. 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 cell's functions.
It also holds the genetic material for eukaryotes. So the nucleus holds the DNA. Prokaryotes,
again do not have membrane bound organelles, so they do not have a nucleus. So there DNA
is organized in a different manner and it's not as nicely organized either as it is in
a eukaryote cell. 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. If a 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, are a type of eukaryote. They have something
called a chloroplast that animal cells don't have, because animal cells can not make sugar
from the sun. Or say we are 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. They have more than a lot of other cells, because they
have to produce so much energy. So the types of organelles and the quantity of them can
vary slightly because you have these different cell functions. Well that's it for the amoeba
sisters and we remind you to stay curious!