Bones of the Human Body

When we are babies, our bodies are made up of 350 bones. As we grow our bones come together so when we are adults, we have about 206 bones. They just don't disappear into thin air, no they build and grow together. (See Exhibit A)

The bones in the skeleton have different jobs. They protect other parts of the body, and they also work together to make some different body parts move.

Our bones contain both living and non-living things. Minerals are non-living things that make the bone hard and strong. The outer part is the hardest part of the bone. The inner part is called sponge bone, and the center part of the bone is called marrow. In some bones there is yellow marrow, which is mostly fat cells. Other bones contain red marrow, which is where red blood cells are produced.

A thin layer called the periosteum covers bones except out joints. The periosteum are living cells that help bones grow and also repairs broken bones. Ligaments hold the bones together in a living skeleton, which we are today. Tendons are cords that connect muscles to bones. The places where our bones come together (kind of like a puzzle) are called joints. Between the moveable joints there is found matter called cartilage.

The hand is made up of twenty-seven bones. There are eight bones known as the wrist and are arranged in two rows; the palm consists of five bones and the remaining fourteen bones make up our fingers. (See Exhibit B)

The backbone is also called the spine. The bones that make up the backbone are called vertebrae. As a child you have thirty-three vertebrates, where an adult has only twenty-six vertebrates. (See Exhibit C)

The skull is made up of twenty-two bones. They protect the brain, eyes, nose, ears, and the tongue. Our teeth are attached to the skull and the jawbone. (See Exhibit D)

The ribs help protect the organs of the body such as the heart and the lungs. There are two collarbones. They are connected to the breastbones and arm socket of the shoulder blade. The bones are connected to the wrist bone. There are eight wrist bones, which are called carpals.

The femur is the largest bone in the skeleton. The femur is connected to the hip bone in the ball-and-socket joint. The ankle bones are called the fibula and tibula. The foot consists of twenty-six bones. There are seven short tarsal bones which we call the heel; five bones found in the front of the instep make the ball; and the remaining fourteen bones make up the toes. (See Exhibit E)

Now when someone asks you how many bones does the body have, you'll beable to tell them as well as a little bit about their functions.