Connective tissues (one of the four main tissues in human body; the others are epithelial tissues, muscular tissues and nervous tissues) which carry out many important functions in our body are made of three components: cells, fibers and ground substance. There are at least three types of fibers: collagenous, elastic and reticular fibers. All of three types of fibers and the ground substance are produced by fibroblasts which are the main own or stationary cells in these kinds of tissues.

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