Structure of Skeletal System
Structure of the Skeletal System
Framework of the Bones
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The skeletal system's architecture consists of 206 bones, providing structure to the human body.
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These bones vary in shape and size, from the long thigh bone (femur) to the small auditory bones.
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The major categories comprise long bones, short bones, flat bones and irregular bones.
Spine Composition
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The spine plays a crucial role by providing support to the torso, and consists of 33 individual bones.
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Formed of five sections, it contains the cervical, thoracic, lumbar, sacrum and coccyx.
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The vertebral column provides a central axis for the body, protecting the spinal cord.
Joint Types
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Fixed or fibrous joints permit insignificant or no mobility; sutures in the skull are an example.
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Cartilaginous joints allow limited movement, like the vertebrae in the spine.
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Synovial joints have a high range of motion, like the elbow or knee.
Bones and Bone Tissue
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Bones are composed predominantly of calcium phosphate, offering them strength.
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The outside layer of bone (periosteum) forms a hard compact bone layer.
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Compact bone protects the internal network of spongy bone, also known as cancellous bone.
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Spongy bone tissue is porous for lighter weight without weakness.
Bone Marrow
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Situated inside the majority of bones, bone marrow produces new blood cells.
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Comes in two types: red and yellow. Red produces blood cells, while yellow stores fat.