Fibrous connective tissue
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In zootomy, fibrous connective tissue (FCT) is a type of connective tissue which has relatively high tensile strength, due to a relatively high concentration of collagenous fibers. Such tissues form ligaments and tendons; the majority of the tissue does not contain living cells, the tissue is primary composed of polysaccharides, proteins, and water.
Types
There are several categories of FCTs:
- Loose connective tissue supports most epithelia and many organs. It also surrounds blood vessels and nerves. Cells called fibroblast are widely dispersed in this tissue. They are irregular, branching cells that secret strong fibrous proteins as an extracellular matrix. The most commonly secreted protein is collagen which represents one-fourth of all vertebrate protein. Collagen is tough and flexible and gives strength to tissue.
- Elastin fibers, which are also thinner than collagen fibers, are also secreted by fibroblasts. They are composed of protein fibers with longer cross-links than those of collagen. This structure gives elastin fibers great elasticity.
- Dense connective tissue
- Dense, iregular connective tissue contains fibroblast cells that secrete collagen fibers. The fibers are not arranged in parrallel bundles as is dense, regular connective tissue. This tissue comprises a large portion of the dermal layer of skin.
- Dense, regular connective tissue provides strong connection between different tissues. Dense connective tissue contains fibroblasts which secrete collagen fibers. The collagen fibers are bundled in a parallel fashion. Tendons, which connect muscle to bone, derive their strength from the regular, longitudinal arrangement of bundles of collagen fibers. Ligaments bind bone to bone and are similar in structure to tendons.
- Elastic connective tissue
- Reticular connective tissue