The skeletal system is a huge part of what makes us human; of course, we couldn't survive without it. But what is the skeletal system, exactly? We all know what a skeleton is, but the skeletal system is much more than just the inspiration for spooky Halloween decorations. There is a lot to learn about it, and experts discover more every day.
The skeletal system, as the name implies, starts with your skeleton. It is the framework of bones that make up your body. It is the arm bone that connects to your shoulder bone, your shin bone that connects to your knee bone, and every other lyric to that old children's song. But the skeletal system is more than just bones: it is also made up of the tendons, cartilage, and ligaments that connect those bones and help them to carry out their respective functions.
You mean aside from being a frame to hang our skin on? A lot, actually! The human skeletal system performs many vital functions necessary for a human being to live and move. It supports muscles, it facilitates movement, and it protects our internal organs from outside damage. It is also the location of blood cells production and calcium storage. In short, it allows us to survive in this world.
The adult human skeletal system is made up of 206 bones. Each of these bones has a different purpose and is a different size and shape. You might be interested to learn, though, that babies are born with approximately 300 bones. These bones fuse and grow together to create the number we end up with as fully grown adults. The individual bones can grow as well, which is how we reach our final, adult height.
Bones in a living body are not the same as the bones in a dinosaur skeleton at a museum. Living bones are made up of several layers. The first is the periosteum, a thin, dense membrane of nerves and blood vessels that delivers sustenance to the bones. The second layer is compact bone: the hard, smooth material we all recognize. Inside this layer is cancellous bone, a spongy substance that contains the most interior bone layer: the marrow. Bone marrow is a thick, gel-like substance that produces blood cells.
As mentioned previously, babies are born with 300 bones, which grow and fuse to narrow that number down to 206. But at what point do bones stop growing and changing? This is different for each person, but the median age for the end of bone growth is 25 years. Bones and cartilage begin as soft and malleable and harden over the year. At this age, the growing stops, and the bones are as big as they will ever get.
Every mother and father in the world tell their child to drink more milk to build strong bones. This is not just parental nagging: calcium is vital to bone development and maintenance. When a child's bones are growing and switching from cartilage to bone (or simply growing into other, bigger bones), they need calcium for nourishment and strength. Even as an adult, it is important to keep calcium in your diet, especially when women enter menopause when bones begin to weaken.
The largest bone in the body is the femur, otherwise known as the thigh bone. The smallest bones are in the middle ear -- these tiny bones help you to hear, so they pack a lot of punch for such small components. Both types of bones are completely different in size and shape, but they are equally important to our bodies as a whole.
The spine is one of the most important parts of the human skeletal system. It allows you to move, and twist, and walk, and holds your body upright. It protects a large bundle of nerves called the spinal cord, which acts as an information superhighway between your brain and the rest of your body. 33 different interlocking bones make up the spine, each of which carries out a different function. These vertebrae help you do everything from hold your head up to pick up heavy things without falling over.
We may all be created equal in some ways, but this isn't technically true when it comes to our skeletal system. The female skeletal system includes a flatter, larger, more rounded pelvis bone to enable giving birth. A male's pelvis is smaller and is at a more acute angle to his body. Most of the differences between the male and female skeletal system are related to reproduction, as men and woman are biologically designed to take on different roles in this process.
Yes, they are! Teeth are not defined as bone, but they are still an integral part of the skeletal system. In fact, they are stronger than bones: experts now know the dentin and enamel that make up our teeth are the most durable substances in our bodies. This is why many of the skeletons of people who lived thousands of years ago still have the teeth attached when much of the rest of the body is gone.
This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.