Specialised Connective Tissue 2: Cartilage Flashcards
What are the functions of cartilage?
Can bear mechanical stresses without permanent distortion due to firm consistency of extracellular matrix
Supports soft tissues
Shock-absorbing because it is resilient
Smooth surface allows sliding
Essential for growth and development of bone
Features of cartilage
Modified connective tissue
Forms skeletal basis of some parts of body
Matrix is firm, giving it the characteristic consistency
Avascular (nutrients diffuse from the perichondrium)
Perichondrium is rich in blood vessels
What are chondroblasts?
Progenitor of chondrocytes
Location of chondroblasts
Border between perichondrium and matrix
Functions of chondroblasts
Secretes type II collagen and other ECM components
What are chondrocytes?
Mature cartilage cells
Location of chondrocytes
Reside in a space called the lacuna
What is the purpose of the matrix?
Provides the rigidity, elasticity, & resilience
The matrix is basophilic
What are the components of the matrix?
Fibers
Ground substance
What types of fibers make up the matrix?
Collagen
Elastic
What are the components of the ground substance?
Glycosaminoglycans (chondroitin sulfates & keratan sulfate)
Proteoglycans
Water
What are the types of cartilage growth?
Appositional
Interstitial
What is appositional growth?
Increasing in width of cartilage
Chondroblasts deposit matrix on surface of pre-existing cartilage
What is interstitial growth?
Increasing in length of cartilage
Chondrocytes divide and secrete matrix from within the lacunae
What are the types of cartilage?
Hyaline
Elastic
Fibrous
What is perichondrium?
Vascular connective tissue
What are the layers of perichondrium?
Outer fibrous layer: Formed from dense fibrous connective tissue
Inner chondrogenic layer: Contains chondroblasts (no lacunae). They secrete cartilage matrix and give rise to chondrocytes
What are the sites of hyaline cartilage?
Tracheal rings
Nasal septum
Larynx
Costal cartilage
Articular surfaces of joints
Describe the arrangement of cartilage cells in hyaline cartilage
Present singly or in groups of 2 or 4 cells inside lacunae
Types of fibers in cartilage matrix in hyaline cartilage
Collagen type II
Describe the ground substance of hyaline cartilage
Homogenous
Clearly basophilic
Function of hyaline cartilage
Support
What are the sites of elastic cartilage?
Auricle
External auditory meatus
Auditory tube
Epiglottis
Apices of arytenoid cartilage
Describe the arrangement of cartilage cells in elastic cartilage
Larger
More numerous
Packed more closely
Types of fibers in cartilage matrix of elastic cartilage
Elastic fibers
Collagen type II
Describe the ground substance of elastic cartilage
Rich in elastic fibers
Function of elastic cartilage
Support
What are the sites of fibrocartilage?
Intervertebral discs
Pubic symphysis
Manubriosternal joint
Articular disc of temperomandibular joint
Describe the arrangement of cells in fibrocartilage
Fewer
Small
Scattered singly or in rows
Types of fibers in cartilage matrix of fibrocartilage
Collagen type I and II
Describe the ground substance of fibrocartilage
Acidophilic
Functions of fibrocartilage
Supportive with tensile strength
