Connective Tissue

Connective Tissue. The connective tissues serve as a kind of framework or basis on which the body is moulded or built up; they are disposed between the various muscular, glandular, and nervous structures, connecting them one with another, whence the name connective tissues. The connective tissues are developed from mesoblast; they may be divided into three groups, connective tissue proper, cartilage (q.v.), and bone (q.v.). Connective tissue proper or fibrous connective tissue is made up of cells and intercellular substance. The chemical basis of the latter is composed of a material which yields gelatin on boiling. The cells are readily distinguishable on microscopic examination of such structures as tendon and cornea; while, to go to the other extreme, there are structures in which the matrix or intercellular substance reaches such a degree of development as to render it difficult to demonstrate the existence of cells at all. Several varieties of the connective tissues (apart from cartilage and bone) are described. White fibrous tissue occurs in tendons and fasciae and beneath the epidermis; yellow elastic tissue is found in the coats of arteries and in certain elastic membranes; adenoid tissue is that which constitutes the framework of lymphatic glands; gelatinous tissue is found in the umbilical cord; and neuroglia in nervous structures.