The three meninges, membranes that envelop the brain and spinal cord, are composed of connective tissue.

Most types of connective tissue consists of three main components: elastic and collagen fibers, ground substance, and cells.

The term "connective tissue" (in German, Bindegewebe) was introduced in 1830 by Johannes Peter Müller.

[9] Dense regular connective tissue, found in structures such as tendons and ligaments, is characterized by collagen fibers arranged in an orderly parallel fashion, giving it tensile strength in one direction.

[citation needed] Special connective tissue consists of cartilage, bone, blood and lymph.

[19] Ground substance is a clear, colorless, and viscous fluid containing glycosaminoglycans and proteoglycans allowing fixation of Collagen fibers in intercellular spaces.

Type I collagen is present in many forms of connective tissue, and makes up about 25% of the total protein content of the mammalian body.

[22] Connective tissue has a wide variety of functions that depend on the types of cells and the different classes of fibers involved.

Loose and dense irregular connective tissue, formed mainly by fibroblasts and collagen fibers, have an important role in providing a medium for oxygen and nutrients to diffuse from capillaries to cells, and carbon dioxide and waste substances to diffuse from cells back into circulation.