Characteristics of Cartilage

Definition and Characteristics of Cartilage

• Cartilage is a type of connective tissue (CT) that is rubbery and flexible to bear mechanical stress.
• It arises from the umbilical mesenchymal stem cells (UMCS).
• Cartilage cells are widely separated by a considerable amount of intercellular material (matrix).
• The matrix is rubbery (firm) but flexible, avascular (non-vascular), and nourished by diffusion of O2 and nutrients from the surrounding CT or synovial fluid in the joint cavities.
• Cartilage has no lymph vessels and no nerves.

Functions of Cartilage

• Supports tissues, tissue attachment, and weight bearing.
• Provides shock-absorbing functions.
• Offers a smooth sliding surface for joints, allowing for easy movement of bones.
• Keeps airway patent.
• Plays a role in the development and growth of bones, both before and after birth.

Composition of Cartilage

• Cartilage is composed of cells, fibers, and matrix.
• The cells are called chondroblasts and chondrocytes.
• The fibers consist of variable amounts of collagen and elastic fibers.
• The matrix is abundant, firm, and rubbery.
• Cartilage is covered by a connective tissue covering called perichondrium.

Types of Cartilage

• There are three types of cartilage based on the amount of ground substance and type of fibers.
• The three types are:

Hyaline Cartilage

• Mainly composed of type 2 collagen fibers.

Yellow Elastic Cartilage

• Abundant elastic fibers and some type 2 collagen fibers.

White Fibrocartilage

• Abundant type 1 collagen fibers and some type 2 collagen fibers.
• Hyaline cartilage has the typical structure of cartilage, while the other types are considered variants of its basic structure.