The cartilage of the skeleton is formed by cartilaginous tissue, highly resistant to wear, they are devoid of blood vessels, and nutrition is carried out through diffusion from the surrounding tissues; outside they are covered by the perichondrium. Intervertebral discs, articular surfaces, and parts of the ribs consist of cartilage. Distinguish between hyaline, fibrous and elastic cartilage. The bone part consists of osteocytes and osteoblasts and an intercellular substance containing fibers and inorganic compounds, permeated with blood vessels that provide bone nutrition. Between the bone cells, there are plates that intersect in certain directions, along the lines of greatest load; the outside of the bone is covered with the periosteum.
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