Remember, cartilage is a type of connective tissue. And inside cartilage found inside the human body, we basically have a protein, a structural protein known as collagen that we discussed earlier, as well as a proteoglycan known as agricon. And together these molecules basically combine to form our extracellular matrix. And the extracellular matrix in our cartilage basically gives cartilage the ability to be flexible. A cartilage is also found between bones and cartilage also basically acts as a shock absorber. So when we jump, the reason that our bones don't rub together is a result of the cart carclage found between those bones.