Examples include the cranial (skull) bones, the scapulae (shoulder blades), the sternum (breastbone), and the ribs. The term “ flat bone” is somewhat of a misnomer because, although a flat bone is typically thin, it is also often curved. Short bones provide stability and support as well as some limited motion. The only short bones in the human skeleton are in the carpals of the wrists and the tarsals of the ankles. Short BonesĪ short bone is one that is cube-like in shape, being approximately equal in length, width, and thickness. Long bones function as levers they move when muscles contract. Long bones are found in the arms (humerus, ulna, radius) and legs (femur, tibia, fibula), as well as in the fingers (metacarpals, phalanges) and toes (metatarsals, phalanges). Keep in mind, however, that the term describes the shape of a bone, not its size.

Long BonesĪ long bone is one that is cylindrical in shape, being longer than it is wide. Bones are classified according to their shape. Their shapes and their functions are related such that each categorical shape of bone has a distinct function.įigure 10.2.1. The 206 bones that compose the adult skeleton are divided into five categories based on their shapes (Figure 10.2.1).

Describe the function of each category of bones.

Classify bones according to their shapes.

Bradley and J.By the end of this section, you will be able to:

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How Many Bones Are There in the Human Body?. it protects other organs and provides a framework for muscles to attach. Flat bones are mainly found in the skull, ilium, sternum and ribcage and are made of two thin layers of compact bone, with a layer of cancellous bone in between them. They provide strength, structure and mobility.

the shaft contains a cavity filled with bone marrow. Long bones, such as the femur (thigh bone), are made up of a long shaft and two ends. In the human skeleton, there are two main types of bone: long bones and flat bones, and three others - short, irregular and sesamoid. These bones make up the skeletal system which helps support the body and aid in movement. Children have more bones (270 as an infant), as bones in the skull are separate and have not yet fused together ( ossification). There are two-hundred and six bones in the adult human body.

Where are flat bones found