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Cartilage

This video covers the origins and functions of cartilage and collagen.

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Created by Tracy Kim Kovach.

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  • leaf yellow style avatar for user Jacob Winters
    So what kind of cartilage is your nose made of? Part of it is cartilage, isn't it?
    (15 votes)
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  • leaf green style avatar for user studentn
    This might be a silly question, but if cartilage isn't innervated, how come ear piercings hurt?
    (13 votes)
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  • piceratops seed style avatar for user HKGearhart
    I have an idea that Hyaline, Elastic, and Fibrous cartilage are comprised by different ratios of the Collagen and Elastin proteins. Would it be alright to understand them as:
    Hyaline - 50% Collagen 50% Elastin
    Elastic - around 100% Elastin
    Fibrous - around 100% Collagen

    Or are these estimations nowhere even close to reality?
    (18 votes)
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  • aqualine ultimate style avatar for user Janessa Urban
    Is your hair made up of cartilage?
    (4 votes)
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  • piceratops ultimate style avatar for user Fiona Zee
    Do cartilage have living cells?
    (5 votes)
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  • blobby green style avatar for user govertblom
    at , you tell that you want to 'touch on briefly...' and then you start talking about something related to elastin and elastic protein. unfortunately I really cannot understand what you say there exactly :S (i am sorry I am not a native speaker and just this tiny bit of information went too fast for me :( ) could you explain it again for me?
    (2 votes)
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    • blobby green style avatar for user rebeccaluoh23
      She said she wanted to "touch on briefly what I had struggled with for a little while...," which is the difference between cartilage and collagen. She then explained that cartilage is the connective TISSUE that's made up of collagen (a PROTEIN) and elastin (another protein). I've definitely confused those before as well. Hope this helps!
      (9 votes)
  • spunky sam blue style avatar for user viveka rajasekaran
    what is elastin
    (3 votes)
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  • male robot donald style avatar for user Michael Spivey
    Does cartilage have veins and artery's in them just like the rest of your body?
    (1 vote)
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  • blobby green style avatar for user Ramero Russell
    I find it very interesting that the Joints in your wrist weren't even mentioned, or even classified as Hyaline Cartilage. Why so?
    (3 votes)
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  • starky tree style avatar for user Isaac
    What does it mean "absorb shock"?
    (1 vote)
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    • piceratops ultimate style avatar for user Adrian
      It probably means that in great quantities, (meaning if an area has a thick amount of cartilage)it might help absorb the shock. Assuming you don't mean actual ELECTRIC shock, imagine a huge amount of, say, quicksand in a room. Then, try hitting it with as much force as you can muster. Then, assuming YOU, the person who threw the punch, didn't break any bones, look at the quicksand, and you will see it absorbed the kinetic energy, which MIGHT be classified as 'shock'. Now, instead of quicksand, replace the contents of the room with cartilage. Now, punch it. Presumably, the force SHOULD be reduced, but this is just a theory. PS, a large amount of cartilage MIGHT take the brunt off some of the actual electric version of the 'shock'. Hope this helped, Isaac!
      (2 votes)

Video transcript

- [Instructor] Alrighty, so we're talking about cartilage, and cartilage is, at the most basic level, a connective tissue that can be found throughout the entire human body. And so cartilage is an extracellular tissue secreted by cells called chondrocytes, which are derived from the same precursor cells as bone, the fibroblast. Now chondrocytes secrete fibrous materials such as collagen, which is a strong fibrous protein, and elastin, which as it's name sort of sounds like, is an elastic protein that provides a rubbery, elastic component to cartilage. And one thing that I just wanted to touch on briefly is something that I personally sort of struggled with for a little while before I realized, ah that's what it is. So cartilage basically is, as I said, a connective tissue, just like bone, just like fat and other connective tissues that you find in the body. Collagen, on the other hand, is one of the building blocks of cartilage. So, I feel like sometimes it was easy for me to confuse these two terms, but realize that cartilage is actually referring to the type of tissue and collagen is referring to the type of protein that is found in cartilage. Now the key thing to remember about collagen and elastin, that make up cartilage, is that it gives cartilage strength and flexibility. And a couple of other key points to remember about cartilage is that it is not innervated, meaning it doesn't have nerve cells, and it is also avascular, meaning it doesn't have any vasculature that runs through it. In other words, it doesn't have arteries and veins and blood vessels that run through. Instead, cartilage receives nutrition and immune protection from the surrounding fluid. So, there are three main types of cartilage found within the body. The first type is called hyaline cartilage. So, you can find hyaline cartilage in the larynx and trachea in the throat portion of the body, and then also in all of the joints where the surfaces of bones are articulating each other. So this is called articular cartilage. And, the main purpose of hyaline cartilage is to reduce friction and absorb shock. The second type of cartilage that you will find in the human body is called elastic cartilage, which can be found in the shape of the outer ear, and also the epiglottis which is the structure that protects your airway whenever you are swallowing food. And so the main purpose of elastic cartilage is to provide shape and support. And then finally we have fibrous cartilage. And you can find fibrous cartilage in the intervertebral discs in the spine and also in an area of the pelvis called the pubic symphysis which is where the two halves of your pelvic bones come together to form a joint there. And the main purpose of fibrous cartilage is to provide rigidity and to absorb the shock that is transmitted between these joints.