Connective tissues are composed of cells and intercellular matrix. The intercellular matrix is made up of fibers and a ground, which is a fluid or gel. The makeup of the intercellular matrix determines the type and strength of the connective tissue. The three types of fibrous connective tissues are collagen, elastic and reticular.
Collagen fibers are long, straight and unbranched fibers. They are the most common type of fiber found in the body and are both strong and flexible. In tendons and ligaments, collagen fibers are parallel to one another, providing tensile strength along the direction of stress.
Elastic fibers are made out of the protein elastin. The fibers are wavy and have branches off each fiber. The fibers are strong and very flexible, returning to their original size after being stretched. Elastic cartilage is made out of elastic fibers and is found in the external flap of the ear, the epiglottis and the tip of the nose.
Reticular fibers are made out of thin strands of collagen fibers with a glycoprotein coating. Reticular fibers branch and create net-like structures within the body. Reticular fibers can be found on many organs of the body such as the lymph nodes, thymus, spleen and bone marrow. Reticular fibers are the least common type of connective tissue fiber in the body.
Other Types of Connective Tissue
The connective tissues of the body are classed as loose, dense, bone or blood and lymph. Each type of connective tissue uses fibrous proteins, except for blood. The matrix of blood is plasma which is a protein suspended in fluid that provides the cushion between individual blood cells.