Bones how many

It also protects the spinal cord, a large bundle of nerves that sends information from your brain to the rest of your body. The spine is special because it isn't made of one or even two bones: It's made of 33 bones in all! These bones are called vertebrae say: VER-tuh-bray and each one is shaped like a ring. In between each vertebra the name for just one of the vertebrae are small disks made of cartilage.

These disks keep the vertebrae from rubbing against one another, and they also act as your spine's natural shock absorbers. When you jump in the air, or twist while slamming a dunk, the disks give your vertebrae the cushioning they need. Your heart, lungs, and liver are all very important, and luckily you've got ribs to keep them safe. Ribs act like a cage of bones around your chest.

It's easy to feel the bottom of this cage by running your fingers along the sides and front of your body, a few inches below your heart.

If you breathe in deeply, you can easily feel your ribs right in the front of your body, too. Some thin kids can even see a few of their ribs right through their skin.

Your ribs come in pairs, and the left and right sides of each pair are exactly the same. Most people have 12 pairs of ribs, but some people are born with one or more extra ribs, and some people might have one pair less. All 12 pairs of ribs attach in the back to the spine, where they are held in place by the thoracic vertebrae. The first seven pairs of ribs attach in the front to the sternum say: STUR-num , a strong bone in the center of your chest that holds those ribs in place.

The remaining sets of ribs don't attach to the sternum directly. The next three pairs are held on with cartilage to the ribs above them. The very last two sets of ribs are called floating ribs because they aren't connected to the sternum or the ribs above them.

But don't worry, these ribs can't ever float away. Like the rest of the ribs, they are securely attached to the spine in the back. Your skull protects the most important part of all, the brain. You can feel your skull by pushing on your head, especially in the back a few inches above your neck.

The skull is actually made up of different bones. Some of these bones protect your brain, whereas others make up the structure of your face. If you touch beneath your eyes, you can feel the ridge of the bone that forms the hole where your eye sits.

And although you can't see it, the smallest bone in your whole body is in your head, too. The stirrup bone behind your eardrum is only. Want to know something else? Your lower jawbone is the only bone in your head you can move.

It opens and closes to let you talk and chew food. Your skull is pretty cool, but it's changed since you were a baby. All babies are born with spaces between the bones in their skulls. This allows the bones to move, close up, and even overlap as the baby goes through the birth canal. As the baby grows, the space between the bones slowly closes up and disappears, and special joints called sutures say: SOO-churs connect the bones.

As you sit and type at the keyboard, while you swing on a swing, even when you pick up your lunch, you're using the bones in your fingers, hand, wrist, and arm.

Each arm is attached to a shoulder blade or scapula say: SKA-pyuh-luh , a large triangular bone on the upper back corner of each side of the ribcage.

Bones are made of connective tissue reinforced with calcium and specialised bone cells. Most bones also contain bone marrow, where blood cells are made.

Bones work with muscles and joints to hold our body together and support freedom of movement. This is called the musculoskeletal system. The skeleton supports and shapes the body and protects delicate internal organs such as the brain, heart and lungs. The body is constantly building up and breaking down bone tissue as required. Healthy bone needs a balanced diet, regular weight-bearing exercise and the right levels of various hormones. Bone marrow is where blood cells are made.

The three different types of blood cell made by bone marrow include:. Our body is constantly remodelling its skeleton by building up and breaking down bone tissue as required. As a result, each bone is rebuilt from scratch about every decade.

The bone cells involved in this process include:. This page has been produced in consultation with and approved by:. The abdominal muscles support the trunk, allow movement and hold organs in place by regulating internal abdominal pressure.

Acromegaly is caused by an excess of growth hormone in adults, which causes the overgrowth of bones in the face, hands, feet and internal organs. Located in the wrist and ankle joints, short bones provide stability and some movement. The carpals in the wrist scaphoid, lunate, triquetral, hamate, pisiform, capitate, trapezoid, and trapezium and the tarsals in the ankles calcaneus, talus, navicular, cuboid, lateral cuneiform, intermediate cuneiform, and medial cuneiform are examples of short bones.

Irregular bones vary in shape and structure and therefore do not fit into any other category flat, short, long, or sesamoid. They often have a fairly complex shape, which helps protect internal organs. For example, the vertebrae, irregular bones of the vertebral column, protect the spinal cord. The irregular bones of the pelvis pubis, ilium, and ischium protect organs in the pelvic cavity.

Sesamoid bones are bones embedded in tendons. These small, round bones are commonly found in the tendons of the hands, knees, and feet. Sesamoid bones function to protect tendons from stress and wear. The patella, commonly referred to as the kneecap, is an example of a sesamoid bone. See more from our free eBook library. Bony bonafide bones.

These skeletal building blocks inspire curiosity and spark fear in different folks—we hope our stories, covering everything from surgeries and supplements to good old-fashioned boning, will only do the first.

Here are some crazy but important facts you might not know about your bones to make you appreciate each one, no matter how big or small. We start our lives with much more osseous matter than we end them with. Newborns can have more than distinct bones. Instead, they start as tough yet flexible cartilage, which allows a fetus to stay curled up in utero and squeeze through the birth canal during labor without hurting itself. But once a baby takes its first breaths, its bone-forming cells are hard at work to ossify that cartilage—or turn it into sturdier bone—and join all the pieces together.

Take the humerus, the upper arm bone: It starts as three or four separate pieces of cartilage. After birth, the cartilage that makes up each piece begins to transform, individually, into bone.