21 Interesting human body facts about the human skeleton

Cracking your knuckles will not increase the risk of arthritis. Tweet This

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Although bones appear very hard from outside, inside they look spongy, filled with lots of air. Tweet This

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Bones are up to 50% water. Tweet This

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Adult human body has 206 bones in the skeleton. These are grown together from about 300 bones at birth! Tweet This

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Skull has only one moving part – the mandible (the lower jaw bone). Tweet This

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Skull is made up of 22 different bones which grow together during childhood. Tweet This

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Almost half of all bones in human body are in hands and feet, which allows a great variety of movement. Tweet This

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The Hyoid bone, in your throat, is the only jointless bone in your body, not attached to other bone. Tweet This

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During pregnancy, the hormone relaxin extends a bit the ligaments, thus permitting the bones of the pelvis to relax for the birth. Tweet This

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The longest bone in the body is the femur, connecting the pelvis to the knee. Tweet This

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Your thigh bone (femur) is much stronger than concrete and as strong as granite. Tweet This

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The hardest bone in the human body is the jawbone. Tweet This

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Bones in an adult account for 14% of the body’s total weight. Tweet This

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14 bones make up the human face. Tweet This

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The smallest bone is the stapes, which in Latin means stirrup. Located in the middle ear, it only measures 0.1 inches (0.25 cm). Tweet This

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Bones are broken down and remade constantly, just like skin. All the bones are slowly replaced until they are new bone once every 7 years! Tweet This

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Every second, bone marrow produces two million red blood cells. Tweet This

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We are almost half inch (1 cm) shorter in the evening than in the morning, due to squeezing the cartilage between our bones while standing and sitting. Tweet This

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The human body has 230 movable and semi-movable joints. Tweet This

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When you frown you activate over 40 muscles; you extend your middle finger with just 4. Tweet This

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The sound you hear when you crack your knuckles is actually the sound of nitrogen gas bubbles bursting. Tweet This

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