Cartilage and Skeletal Tissues Overview

Introduction

The skeletal system is composed of both bone and cartilage, each contributing to the structure, support, and function of the human body. Understanding the properties and roles of these tissues is essential for studying anatomy and physiology.

Cartilage and Bone Functions

Types and Properties of Cartilage

Cartilage is a specialized connective tissue found throughout the skeleton. It is resilient, flexible, and adapted to specific locations in the body.

• General Characteristics:

  • Resilient and sculpted to body location

  • Avascular (lacks blood vessels) and not innervated (no nerves)

  • Consists primarily of water

  • Extracellular matrix is jelly-like

  • Cells are called chondrocytes

  • Chondrocytes are encased in small cavities called lacunae

• Types of Cartilage:

  • Hyaline Cartilage: Provides support, flexibility, and resilience; contains only collagen fibers. Found in articular (joints), costal (ribs), nasal, and respiratory cartilages.

  • Elastic Cartilage: Contains elastic fibers for greater flexibility. Found in the external ear and epiglottis.

  • Fibrocartilage: Has great tensile strength due to thick collagen fibers. Found in intervertebral discs and menisci of the knee.

Example: The meniscus in the knee is made of fibrocartilage, providing shock absorption and stability.

Major Cartilages of the Adult Skeleton

• Articular cartilage: Covers joint surfaces

• Costal cartilage: Connects ribs to sternum

• Nasal cartilage: Forms the nose

• Intervertebral discs: Located between vertebrae

• External ear: Contains elastic cartilage

Functions of the Skeleton and Bone Tissue

Bones and the skeleton perform several vital functions:

• Support: Framework for the body and soft organs

• Protection: Shields the brain, spinal cord, and vital organs

• Movement: Acts as levers for muscle action

• Mineral and Growth Factor Storage: Stores calcium, phosphorus, and growth factors

• Hematopoiesis: Blood cell formation occurs in red marrow cavities

• Triglyceride Storage: Fat storage in yellow marrow

• Hormone Production: Osteocalcin secreted by bones helps regulate glucose and metabolism

Example: The femur stores minerals and produces blood cells in its marrow.

Additional info:

• Cartilage is essential for joint function and growth during development.

• Bone tissue is dynamic, constantly remodeled throughout life.