Cartilage Overview and Functions

Cartilage Overview

• Cartilage is a specialized connective tissue (CT) that lacks blood vessels (avascular).
• Its matrix is firm or rubbery, promoting resilience.
• Cartilage provides support, keeps airways open, provides smooth joint surfaces, and acts as a shock absorber.

Learning Objectives

• Define cartilage
• Classify cartilage types
• Identify cartilage locations in the human body
• Understand cartilage microstructure

Cartilage Cells

• Chondrogenic cells are the mother cells for all cartilage cell types.
• Chondroblasts are immature cartilage cells found on the cartilage surface and perichondrium. They produce the cartilage matrix and fibers.
• Chondrocytes are mature cartilage cells, completely surrounded by their secreted matrix and housed within lacunae. They are often clustered in groups of 2, 4, or 8 (cell nests).

Cartilage Fibers

• Cartilage fibers include collagen and elastic fibers, varying based on cartilage type.

Cartilage Matrix (Ground Substance)

• The cartilage matrix is rubbery and basophilic.
• It's composed of glycosaminoglycans (GAGs), glycoproteins, and water.

Types of Cartilage

• Hyaline Cartilage: Contains collagen fiber type II. Found in fetal skeletons, epiphyseal plates, costal cartilages, articular surfaces, and respiratory passages (e.g., nose, trachea).
• Yellow Elastic Cartilage: Contains elastic fibers. Located in the ear pinna, Eustachian tube, epiglottis, and external auditory canal.
• White Fibrocartilage: Contains collagen fiber type I. Found in intervertebral discs, symphysis pubis, mandibular joint, sternoclavicular joint, and acetabulum (e.g., femur head).

Hyaline Cartilage Structure

• Surrounded by perichondrium (except articular surfaces).
• Contains collagen type II fibers.
• Has a significant amount of basophilic matrix produced by chondroblasts.

Yellow Elastic Cartilage Structure

• Contains perichondrium.
• Has elastic fibers within the matrix.
• Matrix amount is less than in hyaline cartilage.

White Fibrocartilage Structure

• Lacks perichondrium.
• Contains collagen type I fibers in thick, parallel bundles.
• Cartilage cells are arranged in rows between the bundles.
• The matrix is very scant.

This quiz covers the essential concepts of cartilage, a specialized connective tissue. It explores its types, locations in the human body, and microstructure, including the roles of different cartilage cells. Test your knowledge on cartilage's functions and its fibrous composition.