If you’ve ever seen a real skeleton or fossil in a museum, You Might Think That All bones are dead. And, although the bones in museums are dry, hard and brittle are the bones of your body are very Different. The bones make up your skeleton That are alive and well, growing and changing as other parts Constantly of your body.
Almost Every bone in your body are Composed of the Same materials:
• The outer surface of the bone Called the periosteum. It is a thin dense membrane contains Nerves and blood That to nourish the bone.
• The next layer of compact bone Consists. This part is smooth and very hard. The part you see When looking at a skeleton.
• Within the compact bone are layers of cancellous bone Many, Which, as STI Suggests name, is like a sponge Rather. Spongy bone is not as hard as compact, But still very strong.
• In Many bones, the spongy part Protects the innermost part of the bone marrow. Bone marrow is a kind of thick gelatin and Its function is to produce blood cells.
How bones grow
When You Were a Baby, You Had tiny hands, tiny feet … it was extremely small in your body! Slowly, as you’d grow up, everything was growing, your bones Including.
At birth, a baby’s body contains 300 bones About. Eventually, They Will end up merging (bind to grow) in order to join the skeleton of 206 bones of an adult. Some of the baby’s bones are made of a special material Entirely Called cartilage. Other bones of the newborn are Partly Composed of cartilage. The cartilage is soft and flexible. Düring childhood, as you get older, the cartilage gradually ends up Grows Being and bone, with the help of calcium.
When you Have Approximately 25 years, This process is complete. After This Happens, There Will be no more growth: Have Reached Their bones the maximum size. All These bones make up a skeleton That Will Be as strong as mild.
The backbone
The spine is one part of the skeleton That is easy to Identify: try to touch the middle of the back and notice bumps under your fingers STI.
The spine lets Girart stands upright and bend your body and. It Also Protects the spinal cord, a large bundle of Nerves That Transmits information Between the brain and the body. The spine is special Because it is one or two composer of bones, Consists of a total of 26 bones! These bones are vertebrae and Have Called a ring. Different types There are vertebrae in the spine of, and Each have a different function.
• The top seven vertebrae are cervical vertebrae Called. These bones are in the back of the neck, just below the brain and support the Head and Neck. The heavy head is removed, so it is fortunate to Have the help of the cervical vertebrae!
Below the cervical vertebrae • the thoracic vertebrae are, and a total of 12. These are responsible for anchoring the ribs in place. Below the thoracic vertebrae are five lumbar vertebrae and the sacrum is below, Which Consists of five vertebrae fused together to form a single bone.
• Finally, in the lower back is the coccyx, a bone That Is Formed by four fused vertebrae. The lower sections of the spine are important to bear weight and Provide a good center of gravity to the body. So, When wearing a heavy backpack, the lumbar vertebrae are, sacrum and coccyx give you the support. When you dance, jump or Even When You Walk, Maintain These help balance body parts.
Between Each pair of Adjacent vertebrae are small disks made There of cartilage. These disks keep the vertebrae from rubbing together and act as natural shock Also absorbers of the spine. When you jump in the air and turn the trunk to dunk, the disks give your vertebrae the cushioning They need.
Ribs
The heart, lungs and liver are all very important and fortunately With The ribs accounts to Protect Them. The ribs act as a box around the breast bone. It is easy to notice the bottom of your fingers That box with sides and front palpándote of the body A Few centimeters (or inches) below the heart. Sytropin If you breathe deeply, you find it May also easy to see the ribs on the front of the body. Some children Were Even thinner Can See Through the skin the ribs.
The ribs go in pairs, left and right sides and of Each pair are Exactly alike. Most People Have 12 pairs of ribs, But Some People are Born with one or more ribs and a couple Others with less. The 12 pairs of ribs attach in the back of the thoracic spine vertebrae Where the hold Them in place. The first seven pairs of ribs attach to the front of the body at the sternum, a very strong and robust bone Located in the center of the chest That Holds Those ribs in place. Other pairs of ribs are not attached directly to the sternum. The next three pairs are attached to the upper ribs by cartilage.
The last two pairs of ribs are floating ribs Called Because They Are not connected to the sternum or upper ribs by cartilage. But do not worry, These Can not Be Separated ribs from the rest floating. Like the other ribs are firmly attached to the spine from the back of the body.
The skull
The skull Protects the Most Important of all: the brain. You notice the skull apretándote May the head, Especially in the back, A Few centimeters (or inches) above-the neck. The skull is in fact-Composed of Different bones. Some of These Bones Protect the brain, while the structure of Others form the face. If you touch beneath your eyes, you feel the ridge of the bones forming the holes Where the eyes are Accommodated.
And, If You Can not see it, the Small bone of the whole body is in the head Also. The bracket, locate behind the eardrum, measuring only 2.5 to 3.3 mm (or 0.1 to 0.13 inches)! Want to know more? The only bone of the dog head is the lower jaw move. It opens and closes to let you talk and chew food.
The skull is great, But you changed much since You Were a baby. All babies are born with spaces Between the bones of the skull. This allows bones to move, close and overlap as the baby pass through the birth canal. Gradually, as the baby Grows, The Space Between the bones is closing Until It Disappears Completely, and the skull bones are connected together by special joints, street sutures.
Hands
When you use your computer keyboard, you swing on a swing and Even When you take lunch, using the bones of the fingers, hands, Wrists and arms.
Each arm is attached to a shoulder blade or scapula, a large triangular bone at the top and Located back of Both sides of the rib cage. The arm is made up of three bones: the humerus, Which is Above the elbow, the radius and ulna, the elbow Which are below.
Each of These Bones is at the ends and WIDER thinner or narrower at the half, helping to Strengthen the points WHERE They Establish Contact with other bones. At the end of the radius and ulna are eight Smaller bones That make up the wrist. Those howeve small bones, can move! Turn your wrist or handshake and You Will See.
The central part of the hand bones Consists of Five Different. Each finger is composer of three bones, except the thumb, Which Consists of only two. So Between the Wrists, hands and fingers, Have a total of no less Than 54 bones, all ready to help you handle Things, write your name, pick up the phone or throw a ball!
Legs
Of course the bones of the arms, Wrists, hands and fingers are great for picking up the phone, But how are you supposed to approach the machine to answer it? Obviously, With The bones of the legs and feet!
The legs are attached to a circular group of bones Call Your pelvis. The pelvis is a bowl-shaped structure That Supports the spine. It compris two large hip bones in front and the sacrum and coccyx at the back the. The pelvis Acts as a strong ring of protection around hard parts of the digestive system, urinary system and reproductive system.
The leg bones are very large and strong to help support the body weight. The bone from the pelvis That runs to the knee is the femur and is Called the longest bone in the body. In the knee, There Is a triangular shaped bone Called the patella, Which Protects the joint. Below the knee bones There are two: the tibia and fibula. Like the three bones of the arm, the leg ends are at the WIDER Than in the middle, giving Them Greater strength.
The structure of the ankle is a little Different from That of the wrist is the lower leg bones WHERE connect to the large bone of the foot Called the talus. About six other talus bone. But the main part of the foot is similar to That of the Hand, With Five Different bones. Each toe is made up of three tiny bones, except the big toe, Which only have two. This Makes the total foot and ankle bones to be of 52!
Most people do not use the toes or feet to manipulate or to write Things, But Those Used for two very important things: standing and walking. If you do not COOPERATE all the bones of the foot, It Would be impossible to balance properly. The foot bones are structured so That They Are Nearly flat and Slightly wider, Which Helps to stand. So, the next time you walk remember looking down and to thank Those Toes!