Human Anatomy Part 1 - K. A. Dyubenko, A. K. Kolomiytsev, Yu. B. Chaykovsky 2002

General Part
Structure of the Human Body
Tissues - Cartilage Tissue

Cartilage, along with Bone tissue, belongs to Skeletal Tissues as they jointly perform supportive and protective Functions for A number of Organs. Cartilage Cells form a single diferon comprising undifferentiated (stem and semi-stem) cells that actively divide; chondrocytes, which have retained the capacity for proliferation and begun synthesizing Extracellular matrix; and specialized cells (chondrocytes) that actively produce extracellular matrix. The latter consists of fibers and an amorphous ground substance that binds large amounts of Water, which in turn determines the resistance of cartilage tissue to compression and provides high strength and elasticity.

There are three MAIN TYPES OF cartilage tissue, which differ in The Structure of their extracellular matrix: hyaline, elastic, and fibrocartilage.

Hyaline cartilage (Fig. 7B) covers the articular surfaces of tubular bones, forms the costal cartilage, and is part of the Larynx, Trachea, and major Bronchi. With the exception of cartilage covering articular surfaces, hyaline cartilage is externally covered by the perichondrium, formed of Cytology/practical/45.html">Dense Connective Tissue, which contains undifferentiated cells and Blood Vessels. The latter nourish the cartilage tissue, which itself lacks blood vessels.

Cartilage covering articular surfaces is nourished by synovial fluid. The extracellular matrix of hyaline cartilage consists of Collagen fibers. Chondrocytes located beneath the perichondrium are flattened and typically single. Moving away from the perichondrium, chondrocytes form groups consisting of two or more cells located in common lacunae, which arise from the division of a single Cell and are termed isogenous groups (from Greek isos — equal, genesis — origin, development).

Elastic cartilage differs from hyaline cartilage in that its extracellular matrix contains both collagen fibers with amorphous substance and numerous elastic fibers, which impart high elasticity to this tissue. Therefore, it is found in organs subject to bending (auricles, Nose, laryngeal cartilages, medium-sized bronchi).

Fibrocartilage is found at sites where dense regular connective tissue (ligaments and tendons) transitions into hyaline cartilage. It occurs in intervertebral discs and slightly movable bone joints. The topographic features of fibrocartilage are closely related to its structure. Bundles of collagen fibers from ligaments and tendons penetrate it in large numbers, yet between them lie chondrocytes rather than fibroblasts, which can form isogenous groups.