7.1: Introduction
- Page ID
- 53597
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The skeletal system consists of bones, cartilages, and ligaments throughout the body. Bones are complex organs made up of different types of bone cells, protein fibers, and minerals as well as different types of tissues. The skeletal system provides support and protection to the soft tissues that make up the rest of the body. The skeletal system also provides attachment for muscles to allow movements at the joints, it is a place where to store fat and precious minerals such as calcium and phosphorous. Another function of bones is to house the bone marrow that is involved in the production of the formed element of blood.
Cartilage can be hyaline cartilage, fibrocartilage, or elastic cartilage (three different tissue types). Cartilage cushions joints, provides connections between bones in cartilaginous joints, and create structures (e.g. parts of the nose, outer ears, holding airways open). Ligaments are composed of dense regular connective tissue and connect bones to other bones, stabilizing joints.
Above: (Left) Anterior view of human skeleton. (Right) Posterior view of human skeleton. (Far right) Human auditory ossicles (bones of the middle ear). (Bottom) Views of the middle and inner ear showing auditory ossicles (bottom left) and semicircular canals of the inner ear (bottom right).
In the human body, at birth, there are over 300 bones. Many of these bones that exist at birth fuse together during development, leaving a total of 206 separate bones in the adult, not counting numerous small sesamoid bones. The largest bone in the body is the femur, or thigh-bone, and the smallest is the stapes in the middle ear. The hyoid bone is the only bone in the human body that does not articulate (form a joint) with another bone. Instead, the hyoid is attached to a variety of soft tissues including cartilage and muscles.
Attribution
- "Anatomy and Physiology I Lab" by Victoria Vidal is licensed under CC BY 4.0
- Human skeleton with left arm extended; front and back views; Wellcome V0008044.jpg by the Wellcome Collection, a website operated by Wellcome Trust, a global charitable foundation based in the United Kingdom and is licensed under CC BY 4.0
Updated 2025.