HH cartilage

Cartilage

is a tough, durable supporting connective tissue characterized by an extracellular matrix rich in proteoglycans and glycosaminoglycans interacting with collagen and elastic fibers.

cells are found in cartilage?

chondrocytes

Where are chondrocytes located

located in cavities in the matrix called lacunae

function of chondrocytes

synthesize and maintain all components of the extracellular matrix

main components of cartilage extracellular matrix

type II collagen, proteoglycans, glycosaminoglycans, and water

Why can cartilage act as a shock absorber

Because the matrix contains large amounts of water bound to proteoglycans and glycosaminoglycans

Does cartilage contain blood vessels

No, cartilage is avascular

How do chondrocytes receive nutrients

Nutrients diffuse through the matrix from blood vessels in the surrounding connective tissue (perichondrium)

What connective tissue surrounds most cartilage

perichondrium

function of the perichondrium

provides vascular supply and cells for cartilage growth and maintenance.

What are the three main types of cartilage

Hyaline cartilage, elastic cartilage, and fibrocartilage

What type of collagen is abundant in hyaline cartilage

Type II collagen

What are the main functions of hyaline cartilage

It provides smooth, low-friction surfaces in joints and structural support in the respiratory tract.

Where is hyaline cartilage commonly found

In the respiratory tract, articular surfaces of joints, and epiphyseal plates of long bones

What distinguishes elastic cartilage from hyaline cartilage

Elastic cartilage contains abundant elastic fibers in addition to type II collagen

Where is elastic cartilage found

In the auricle of the ear, external auditory canal, auditory tube, and epiglottis

What is fibrocartilage composed of

A mixture of hyaline cartilage and dense connective tissue

What type of collagen is abundant in fibrocartilage

Type I collagen along with type II collagen

Where is fibrocartilage commonly found

In intervertebral discs, pubic symphysis, and certain tendon insertions

Why does cartilage repair poorly after injury

Because it lacks blood vessels and has a low metabolic activity

precursor cells give rise to chondroblasts

Mesenchymal cells

the process of cartilage formation called

Chondrogenesis

cells produce cartilage matrix during development

Chondroblasts

What happens when chondroblasts become surrounded by matrix

They become chondrocytes

lacunae

Small cavities in the cartilage matrix that contain chondrocytes

isogenous groups

Groups of chondrocytes derived from a single cell division

What do isogenous groups indicate

Interstitial growth of cartilage

two types of cartilage growth

Interstitial growth and appositional growth

interstitial growth

Growth from division of chondrocytes within the cartilage

appositional growth

Growth by addition of new layers on the surface from the perichondrium

ells are responsible for appositional growth

Chondroblasts from the perichondrium

outer layer of the perichondrium composed of

Dense connective tissue with fibroblasts

inner layer of the perichondrium called

Chondrogenic layer

cells are found in the chondrogenic layer

Chondroblasts and chondrogenic (progenitor/stem) cells

main collagen type in fibrocartilage

Type I collagen

Which cartilage type lacks perichondrium

Fibrocartilage

Which cartilage type also lacks perichondrium in joints

Articular cartilage

function of articular cartilage

Reduces friction and absorbs shock in joints

What glycosaminoglycan is abundant in cartilage matrix

Chondroitin sulfate

What molecule forms large aggregates with proteoglycans in cartilage

Hyaluronic acid

What percentage of cartilage matrix is water

About 60–80%

Why is water important in cartilage matrix

It allows cartilage to resist compression

What is territorial matrix

Matrix surrounding lacunae that stains darker

What is interterritorial matrix

the extracellular matrix (ECM) in cartilage that occupies the spaces between isogenous groups (clusters) of chondrocytes

Why does territorial matrix stain darker

Because it contains more proteoglycans

Which cartilage type has a glassy appearance

Hyaline cartilage

What fibers give elastic cartilage flexibility

Elastic fibers

What is the main function of fibrocartilage

Provides resistance to compression and tension

Where is elastic cartilage commonly found

External ear and epiglottis

What structure does hyaline cartilage form in the trachea

Tracheal rings

What is the function of tracheal cartilage rings

Maintain airway patency

What cartilage type forms the embryonic skeleton

Hyaline cartilage

What process replaces cartilage with bone during development

Endochondral ossification

What cartilage remains in adults at joint surfaces

Articular cartilage

What cartilage type forms intervertebral discs

Fibrocartilage

What cartilage type forms the pubic symphysis

Fibrocartilage

What cartilage type forms the nasal septum

Hyaline cartilage

What cartilage type forms the epiglottis

Elastic cartilage

What tissue surrounds most cartilage and supplies nutrients

Perichondrium

Why is cartilage slow to heal

Why is cartilage slow to heal

What cells maintain cartilage matrix

Chondrocytes

What protein forms collagen fibers in hyaline cartilage

Type II collagen

What fibers dominate fibrocartilage

Thick bundles of collagen fibers

What gives cartilage resilience

Proteoglycans and water

What happens when cartilage calcifies

Calcium salts are deposited in the matrix

What happens to chondrocytes in calcified cartilage

They die

What tissue replaces calcified cartilage during bone formation

Bone tissue

What is the main function of cartilage in the skeletal system

Support and flexibility

What cartilage provides smooth surfaces for joint movement

Hyaline cartilage

What cartilage provides flexible structural support

Elastic cartilage

What cartilage resists both tension and compression

Fibrocartilage

What is the role of cartilage in joints

Reduces friction and absorbs shock

What structure allows diffusion of nutrients in cartilage

The extracellular matrix

What cells originate from mesenchyme to form cartilage

Chondroblasts

What structure houses chondrocytes

Lacunae

What structure surrounds cartilage except in joints

Perichondrium

What characteristic gives cartilage its firmness

Collagen fiber network

What gives cartilage compressive strength

Proteoglycans bound with water

What cartilage type is most flexible

Elastic cartilage

What cartilage type is strongest against pressure

Fibrocartilage

What cartilage type is most abundant in the body

Hyaline cartilage

What cartilage supports bronchi in the lungs

Hyaline cartilage

What cartilage forms the laryngeal framework

Mostly hyaline cartilage

What cartilage type allows bending of the ear

Elastic cartilage

What cartilage type forms the menisci of the knee

Fibrocartilage

What cartilage type is found between vertebrae

Fibrocartilage

What is the function of proteoglycans in cartilage

Bind water and resist compression

What feature makes cartilage translucent

Fine collagen fibers evenly distributed

What cartilage matrix component binds large amounts of water

Proteoglycans

What type of growth increases cartilage thickness

Appositional growth

What type of growth increases cartilage length internally

Interstitial growth

What cartilage cells divide during interstitial growth

Chondrocytes

What structure forms clusters during interstitial growth

Isogenous groups

What tissue type is cartilage classified under

Supporting connective tissue

What characteristic makes cartilage resistant to compression

High water content

What cartilage type contains elastic fibers

Elastic cartilage

What cartilage type contains thick collagen bundles

Fibrocartilage

What cartilage type has a homogeneous matrix appearance

Hyaline cartilage

What is the major role of cartilage in developing bones

Acts as a template for bone formation

What process converts cartilage to bone in long bones

Endochondral ossification