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Organization in the human body

In multicellular organisms, the body is a system of multiple interacting subsystems. These subsystems are groups of cells that work together to form tissues, and organs that are specialized for particular body functions. Organs work together in organ systems to carry out specific functions for the organism. Created by Khan Academy.

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  • piceratops ultimate style avatar for user James Blagg✝
    Question about the brain organ. How do we think? If we close our eyes, how can we imagine a picture? How do cells know what anything looks like if they dont have eyes?
    (18 votes)
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    • piceratops ultimate style avatar for user FrozenPhoenix45
      Are you asking why our brains can think when they are made up of a ton of individual cells that can't perform any of those functions alone?

      If that is your question, here is my answer. That's like asking why two people can lift something heavy while one can't; or why a wave can form out of numerous drops of water when one drop can't create a wave; or why thousands of words can make an epic story when one word is incapable of doing that. All of those cells working together are able to perform processes that they couldn't do themselves.

      Thought is a wave of electrical signals being passed from one neuron to the next in a huge wave of signals that produces thought (yes, our brains run on electricity). Different sections of your brain are responsible for processing those electrical signals in different ways to produce that thought. In short, thought is how our brains respond to stimuli and signals sent from all of our senses, and its ability to store and use that information through the collaboration of all of the 86 billion neurons located there performing their tasks as they are supposed to.

      Those cells know what things look like because of the signals they receive from all the cells in your eyes that do know what things look like, kind of like a telephone game of information being passed along (only with nothing getting distorted and confused). Your eyes tell your brain cells what things look like and the brain can use that information. We can imagine things with our brain recalling previous information of what things look like and sound like and smell like and basically rearranging it into whatever it is we want to imagine, applying past knowledge and information to create something it maybe has never experienced.

      Please keep in mind, this is an extremely simplified explanation of how the brain works

      Does this answer your question? I apologize for my extremely long answer
      (68 votes)
  • marcimus purple style avatar for user JASHWANTH VK
    What happens if cytoplasm is not present in the cell??
    (3 votes)
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    • piceratops ultimate style avatar for user FrozenPhoenix45
      Cytoplasm performs various functions in the cell, so there would be many different effects. To start, cytoplasm binds the organelles, it keeps them suspended within the three-dimensional cell. In the absence of this, organelles would kind of slop together and there would be much empty, useless space in the cell (and if there's anything we know about creation's design, it's that nothing is ever empty and useless; efficiency is the status quo). An additional and related effect the cell membrane would sag and be unable to retain its shape, an unsavory effect in the structure of living things (think of a wilting flower for a basic picture; though technically that has nothing to do with lack of cytoplasm rather lack of water, it gets the image across).

      Also with loss of suspension and shape is the fact that cytoplasm allows for the transport of molecules and nutrients around the cell. Different areas of the cell need different things delivered to them at different times, and the cytoplasm is the means by which they get to those places. Without cytoplasm, proteins would not be able to move around the cell, beneficiary molecules would be aimless, harmful material could not be destroyed or expelled. Needless to say, the cell would be unable to support functions for its own life.

      Finally, cytoplasm is where the first stage of cellular respiration occurs, also known as glycolysis. Without glycolysis, nutrients could not be broken down and therefore the cell would produce no energy. With no energy, there is no life, and the cell would essentially become a motionless husk.

      I apologize for the long answer, but hopefully I have accurately and clearly described some of the biggest effects of the absence of cytoplasm.

      (If anyone has clarification or correction they would like to offer, feel free to comment on it; I shall willingly and eagerly accept it :) ).
      (26 votes)
  • aqualine ultimate style avatar for user JcBoi
    Here's a fact: The Diaphragm is what makes you hiccup!
    (13 votes)
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  • blobby green style avatar for user Mirjakhon Ismailov
    how does the pain that you get another part of the body transfers through the body so fast.
    (5 votes)
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  • blobby green style avatar for user godzillaXultima..:>
    body eqils pain pain eqals oww oww equils STOP YELLING OWWWW
    (9 votes)
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  • blobby green style avatar for user leyla.spindler
    what is your favorite color?
    (6 votes)
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  • leafers sapling style avatar for user no one ^*^
    Bro, my high school bio teacher said we are perfect, and I see why now. So I’m gonna say it agian. Y’all r perfect
    (7 votes)
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  • blobby green style avatar for user ​
    bold of you to think i have a body.
    (4 votes)
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  • area 52 blue style avatar for user aperez96@student.hcs.k12.nc.us
    How much does the sky weigh?"
    (4 votes)
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  • blobby green style avatar for user ~milani~
    How many organ systems can the human body have?
    (3 votes)
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Video transcript

- [Instructor] Have you ever thought about how incredible the human body is? For example, just to name a few things that your body's already been doing today. You are using your lungs to take breaths in and out, your heart's beating without stopping. And your brain is coordinating your body's functions, and at the same time, helping you understand this video. All these body parts are made up of cells, which as you might remember, are the smallest units of life. And it's so amazing that trillions of cells, without thoughts or intentions of their own, can come together to form something as complex as the human body. To help us understand how this occurs, we have to understand how the body is organized. The human body has a hierarchical organization, meaning it's made up of nested layers, each one more complex than the last. In this case, four different layers make up this hierarchy. Cells, which make up tissues. Tissues, which make up organs. Organs, which make up organ systems. And finally organ systems, which help the human body function as a whole. So let's start with cells and tissues. Cells are the smallest unit of life, and the most basic level of organization in the human body. In the human body, not all cells look or work the same. Instead, they're specialized to carry out different functions. After cells, the next level of organization is tissues. A tissue is a collection of similar, specialized cells. And all of the cells that make up a tissue are like a team. They work together to ensure the tissue works properly. For instance, this image shows a section of the type of epithelial tissue that lines the inside of your mouth. This particular tissue is made up of epithelial cells, which are specialized to help protect your mouth from wear and tear. So the next time you're eating a pointy tortilla chip, remember how important this epithelial tissue is. Next up are organs and organ systems. So organs are structures that are made up of multiple different types of tissues, which all work together to help the organ function. And an organ system is a group of organs that work together to carry out complex functions for the body. For instance, the lungs shown here in the diagram are made up of several tissue types that help them expand and contract. These tissue types include epithelial tissue, which is the same type of tissue we talked about earlier in the mouth, and connective tissue. And these tissues work together so that the lungs can carry out their role in the respiratory system, which is the organ system that allows us to respire or breathe. The respiratory system is made up of multiple organs, including the lungs, the trachea, the nose and the diaphragm. When we breathe, our diaphragm which is this muscle right here, contracts. Air is pulled through our nose and trachea, and into our lungs. Here, gas exchange happens and our bodies take in oxygen and get rid of carbon dioxide. Then our diaphragm relaxes and we exhale. The respiratory system, and other organ systems in the body, carry out specific functions that work together to keep us alive. And they do this mostly without us even realizing it. So it might get a little tricky to remember how all four levels of organization cells, tissues, organs and organ systems relate to each other. I like to think of these four different levels, almost like the Russian nesting dolls that fit one inside another. With cells being the smallest doll on the inside. So cells make up tissues. Tissues make up organs. And organs make up organ systems. All of these components come together to make up the human body. So I hope you've learned more about how our body's organization helps us thrive and stay alive. So now use your brain to tell your muscular system to move your arm and give yourself a pat on the back. Because your body and its organized hierarchical system is really awesome.