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(MUSIC)

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I’ll

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never forget a circular red spot I developed on my arm when I was in elementary

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school.

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It left a lasting memory in my mind, because it was something called ringworm and, with

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my active imagination, I thought I was now infected a ring-shaped worm.

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I learned you’ve got to be careful about names, because ringworm isn’t caused by

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a worm at all.

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It’s actually a fungus which it turns out is pretty common and can be carried by many

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things like pets or soil.

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And since up to that point, I was used to antibiotics as a way to treat infections,

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I assumed I’d be given antibiotics.

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But I wasn’t.

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I was given an antifungal cream instead, and it went away.

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So, it made me wonder – what made it different from the bacteria that had made me sick in

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the past?

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Why wasn’t I given antibiotics?

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Well antibiotics target bacteria.

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Antibiotics can destroy bacteria by affecting their ability to reproduce, damaging their

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cell walls, or interfering with their ability to make proteins that they need to survive.

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Just some examples.

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But it turns out bacterial cells and fungal cells are very different cell types.

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In fact, fungal cells have more in common with your cells- which are animal cells- than

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they have in common with bacterial cells.

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And that has a lot to do with the comparison of prokaryotic cells with eukaryotic cells

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which is what we will focus on.

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First, just a refresher---recall that the modern cell theory includes the statement

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that all living things are made of one or more cells.

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All living things.

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In the three domains of life, prokaryotes are organisms that can be bacteria or archaea.

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They are unicellular which means they are single-celled organisms.

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Eukaryotes are organisms that fit all in this last domain Eukarya---eukaryotes may be protists,

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plants, animals, or fungi.

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They can be unicellular or they can be multicellular, which means they can be made up of many cells.

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Like you!

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By the way, just to clarify: the word "prokaryote" is typically used to refer to the organism

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itself.

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When you are describing its cell, you are describing a prokaryotic cell.

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Same for eukaryote- "eukaryote" typically refers to the organism itself and when you are

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describing its cells, those are eukaryotic cells.

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Prokaryotic cells and eukaryotic cells do have a lot in common.

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Both have DNA.

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That’s critical because DNA is the cells’ genetic material.

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Both prokaryotic cells and eukaryotic cells have ribosomes, which are small organelles---an

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organelle being like a “tiny” organ.

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The ribosomes have the important job of making proteins.

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Got to make protein.

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Both cells have cytoplasm, the jelly fluid within cells.

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Both of them have a cell membrane- also known as a plasma membrane- which is critical because

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it controls what goes in and out of the cell and therefore maintaining homeostasis.

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All cells have a cell membrane.

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Now as for cell walls---most prokaryotic cells have cell walls.

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Many eukaryotic cells---plant cells and fungus cells for example—can have cell walls.

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But there are plenty of eukaryotic cells that don’t have cell walls such as animal cells.

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What makes prokaryotic cells and eukaryotic cells different is especially interesting.

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Eukaryotic cells are more complex than prokaryotic[br]cells.

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They tend to be larger than most prokaryotic[br]cells.

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And to help me remember some more differences in this next part, I like to remember that

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“pro” in prokaryote rhymes with “no” and “eu” in eukaryote rhymes with “do.”

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Prokaryotic cells have no nucleus to contain their DNA.

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So, you will find their DNA is not contained within a nucleus; it’s a bit messy here.

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They have no membrane-bound organelles.

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Membrane-bound organelles are fancy organelles that have their own membrane like the nucleus,

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mitochondria, the endoplasmic reticulum, and the Golgi apparatus.

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A big indicator of eukaryotic cells is this nucleus- eukaryotic cells DO have a nucleus

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to contain their DNA.

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Depending on what type of eukaryotic cell it is---it could have different types of membrane-bound

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organelles.

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For example, a plant cell is likely to have chloroplasts while an animal cell would not.

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Wow, look at all this alphabetized vocabulary.

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If you want to try to practice your skills, pause the video and see how many of these

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vocabulary words you can use to compare and contrast prokaryotic cells with eukaryotic

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cells.

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It’s important to grasp that all cells of living things fall in one of these two categories.

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And understanding the characteristics of these two cell types can help us better understand

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the diversity of living things whether they are archaea, bacteria, protists, fungi, plants,

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or animals.

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And in the case of my example- realizing whether an infection you’re dealing with involves

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prokaryotic cells (such as bacteria) or eukaryotic cells (such as the fungus).

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Well that’s it for the Amoeba Sisters, and we remind you to stay curious!