With Halloween just around the corner, spooky skeletons are everywhere this time of year. But how much do you really know about the bones beneath your skin?
For instance, did you know that bones start growing when a baby is still inside its mother’s womb but that the skeleton is only partly complete at birth? From the top of the head to the tiniest toe, adults have 206 bones throughout their bodies. But kids actually have about 300 bone “parts,” according to an online exhibit called “Skeleton Keys” from the Smithsonian National Museum of Natural History.
If you’re wondering what happens to all those extra pieces, well, they fuse together as you age. In fact, a person’s skeleton can keep growing and fusing until their 25th birthday.
Here’s another interesting fact. Even though skeletons are most often associated with the dead, the bones inside your body right now are 100 percent alive. Larger bones such as the hips are hollow and contain a jellylike substance called marrow. Marrow is where the body creates red blood cells, which carry oxygen throughout your body, and white blood cells, which seek and destroy invaders such as bacteria and viruses. Marrow also acts as a storehouse for fats, which are released when the body needs energy. You see, bones do a lot more than help you stand up!
There are also different kinds of bone cells. The outside of all bones is made up of smooth, compact bone, but inside the tips of many bones you’ll find a dense tangle of bone strands, kind of like a sponge or a spider’s web.
The largest bone in the whole skeleton is called the femur, which is in your thigh. The smallest bones are inside your ear, and they are known as the hammer (malleus), stirrup (stapes), and anvil (incus). Also, the human skull isn’t one bone but a three-dimensional puzzle made up of 22 bones.
But that’s nothing compared with your fingers and toes. Believe it or not, more than half of all the bones in your body are found in the hands and feet.
It’s easy to take our bones for granted. After all, we tend to forget they’re even there unless something goes wrong and we break one. But humans are one of a select few animals lucky enough to have a skeleton. In fact, of all the animals discovered by scientists, just 4 percent have bones beneath their skin. The rest are known as invertebrates — animals that lack vertebrae or a spinal column.
So this Halloween, as you eat a lot of candy, make sure to chase it down with a big glass of milk. Your skeleton needs the bone-strengthening calcium. And you need your skeleton.