Middle school biology - NGSS
Within cells, special structures are responsible for particular functions, and the cell membrane forms the boundary that controls what enters and leaves the cell. Created by Khan Academy.
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- So you could see the cell as a "city" almost?(19 votes)
- Technically yes you are correct about having it like that the lysosomes are the police the mitochondria are the factories and the nucleus is where the mayor is.(35 votes)
- The mitochondria is the "power house".(17 votes)
- Yes, also, fun fact, your immune system or your white blood cells think that the mitochondria is not part of the body as millions of years ago, a giant cell ate a smaller cell yet did not destroy it. They worked together and the inside cell became known as a mitochondria. Yet, millions of years later, your white blood cells are still alarmed if mitochondrias float around(5 votes)
- Video: About cells
Literally everybody in the comments:
I love chicken noodle soup!(14 votes)
- Do we need to eat cells to survive?(8 votes)
- Yup...unless you can eat metal and plastic without dying. (Some people can for some reason, but I doubt they gain much calories from it though.)(8 votes)
- Is it just me, or do cells look GROSS..? Ever since I saw this video, every time I eat something, I think of what she said, "Imagine you are eating a huge cell! now isn't that something to noodle on?", it gives me the heebie-jeebies....(9 votes)
- Who doesn't put chicken in their CHICKEN noodle soup!?(8 votes)
- If cells are in animals, and plants aren't we just eating cells?(8 votes)
- No plants are made up of their own type of cells making them a multicellular organism. So you aren't eating cells, you're eating living things, otherwise known as organisms. That should clear up your confusion. Hope it helps.(2 votes)
- at3:12, when the instructor says there are many organelles present in cells, is this meant that there are many more types of organelles, or many more of the same type as mentioned in the video? Thanks.(5 votes)
- I know you're probably not gonna see this, but still.
Cells do have many of the same type of organelles, but she means there are more types. Good question!(6 votes)
- At3:05, the instructor said the cell wall provides structure for the cell. Does this mean cells can come in different forms?(6 votes)
- What does the cell membrane do?
italics bold(4 votes)
- It's kind of like a door. Not only it separates the cell from its outside world, it also lets things in (nutrients, for example) and out (waste, for example) of the cell.(6 votes)
- [Instructor] So let's imagine this scenario. It's cold outside and we want to make a nice hot bowl of chicken noodle soup. Well, we'd probably need to get the ingredients first. We need some chicken bones to give the broth that distinct chicken flavor, some noodles to add that starchy component, carrots and onions to give some sweetness and color. And of course, salt and pepper to provide seasoning. All of these ingredients would come together to make our chicken noodle soup the comfort food that so many people love, but this video is supposed to be about cells. You know, those tiny things that make up all living things on earth. So why am I telling you about chicken soup? Well, just like how each ingredient in chicken soup adds something unique to the soup's overall flavor and texture, a cell's different parts add something unique and necessary for the overall functioning of the cell. So, let's take a look at some of the structures inside a cell and see how their functions come together to allow cells to carry out all the processes of life. So let's explore the parts of a cell starting with the cell's surface. Cells are separated from their outside environment by a cell membrane. You can think of the cell membrane like a fortress gate, because it regulates what comes into and out of the cell, and contained within the cell is a jelly-like substance that fills out the cell and contains its internal parts, this jelly and all the structures within it make up the cell cytoplasm. Unlike chicken soup, the cell parts in the cytoplasm are not just floating around. Instead, they're organized and held in place by an internal structural network. Some of the parts contained within the cytoplasm are called organelles. So what exactly are organelles? Well, organelles are small compartments in the cell that have different structures and functions. The word organelle basically means, mini organ. And just like how our bodies are made up of different organs that work together to help us stay alive, cells contain different organelles that work together to get things done inside the cell. For example, these jellybean shaped organelles here are little energy producing factories called mitochondria. So mitochondria use chemical reactions to break down sugar molecules in order to release energy that the cell can use for other tasks. Another really amazing organelle is the nucleus. You can think of the nucleus as the information database of the cell. It contains DNA which includes the cell's genes. Genes are special instructions that the cell uses to carry out its functions. Moving over to a plant cell, we can see these green organelles called chloroplasts. You might remember that plants carry out photosynthesis. Well, chloroplasts are the organelle's responsible for this process. Plants need food to live, just like animals do. And chloroplasts use photosynthesis to produce sugars that plant cells use as food. Plant cells also have a layer outside their cell membrane called the cell wall, which helps provide structure for the cell. So as you can see, there are so many different parts that make up a single cell. There are many, many organelles present in cells, way more than the handful I mentioned in this video. And what's even more mind blowing is that these diagrams are only simplified versions of what cells actually look like. And just to give you an idea, here's a picture of what a real cell looks like. So when we're talking about cells and using these diagrams as references, keep in mind that these pictures are only simplified models of the real thing. To wrap up this video on cell parts, let's revisit our delicious bowl of chicken noodle soup that I mentioned at the beginning. Each ingredient that we added had a unique function that contributed to the soup's taste and texture. And similarly, our cell's ingredients, its organelles and structures, each contribute a unique function that helps the cell carry out all the tasks necessary for life. So the next time you find yourself in front of a bowl of noodle soup, just imagine that you're eating one enormous cell. Now, isn't that something to noodle on?