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Tracy Kim Kovach 创建




all righty 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 material such as collagen which is a strong fibrous protein and elastin which as its 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 a 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 a vascular 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 in the body the first type is called hyaline cartilage so you can find hyaline cartilage and the larynx and trachea and the throat portion of the body and then also in all the joints where the services 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