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- Discussion:
    - protein polysaccharides account for approx 4.4% of organic components of bone and may be defined as compounds of carbohydrate and 
         protein in which carbohydrate is a polysaccharide attached to a protein by covalent bonds;
    - principle polysaccharide (mucopolysaccharide) of bone is chondroitin-4-sulfate (chondroitin sulfate A);
         - chondroitin sulfates are found in particularly high concentration in proliferative zone of epiphyseal cartilage where they may play 
              inhibitory role in calcification;
    - in certain genetic diseases known as mucopolysaccharidoses, there is mutation-produced deficiency in lysosomal enzyme activity needed 
         to degrade specific mucopolysaccharides, which results in accumulation of mucopolysaccharides within cells of various organs and 
         increased excretion of the polysaccharides into the urine;
    - loss of these polysaccharides from bone and cartilage causes specific skeletal defects such as joint stiffness, (flattened vertebrae,
         generalized) osteoporosis, and hip and thoracic deformities