Connective Tissue Notes

Most abundant and widely distributed tissue in the body Function: Binding, attachment and support (bones, tendons and ligaments, organs)

Protection- bones and adipose tissue Insulation - adipose tissue Storage - of energy and fat soluble substances Transportation - blood

Characteristics Well vascularized – good blood supply Exceptions: tendon and ligament (poor blood supply); cartilage (avascular)

Consists of three basic elements : Cells – basic unit of life Fibroblast - secrete fibers of matrix Macrophages – phagocytize (eat up) bacteria or cell debris Mast cells - produce histamine during inflammation; also involved in allergic responses

Ground substance – composed of water & other material supports and binds cells together, and provides a medium for the exchange of materials

Fiber – tough string-like material embedded in ground substance Extracellular matrix is made up of ground substance and fiber

TYPES OF FIBERS Collagen fibers - made of collagen Tough and only slightly elastic Occur in bundles with the fibers parallel to one another, which gives great tensile strength Found in bone, tendons, and ligaments

Elastic fibers - composed of a protein called elastin Very stretchy and branch and join to form a network. Provide strength to tissues, but allows the tissue to be flexible and stretchy Found in skin, blood vessels, and lungs

Reticular fibers - composed of collagen and glycoprotein Provide support and form loose networks of fibrous tissue Found around fat cells, nerve fibers, and skeletal and smooth muscle cells