Cartilage and Bone Flashcards
Specialized connective tissue
Cartilage and bone are special types of ___
dense regular connective tissue
Cartilage and bone are considered as ___
organs
Cells inside cavities are called ___
lacunae
What are the cells inside the cavities
chondrocytes and osteocytes
The intercellular substance (matrix) is firmer in ___
cartilage
The intercellular substance (matrix) is harder in ___
bone
Makes up the bulk of fetal skeleton
cartilage
Eventually replaced by bone
cartilage
Limited in adults
cartilage
Cartilage does not contain…
blood vessels, lymph vessels, or nerves
Dense regular connective tissue that envelops most cartilage
perichondrium
Perichondrium has ___
chondrogenic potency
Layers of Perichondrium
a. fibrous layer (outer)
b. chondrogenic layer (inner, more cellular)
Cells in cartilage
- chondrocyte
- osteoprogenitor cells
- chondroblasts
Cell in cartilage that vary in size, has cytoplasmic processes, resides in the lacunae, and young cells are capable of mitosis
chondrocyte
Stem cells are found in the chondrogenic layer
osteoprogenitor cells
Osteoprogenitor cells can transform into either…
chondroblasts or osteoblasts
Synthesize precursors of fibers and organic constituents of cartilage matrix
chondroblasts
Can transform into chondrocytes
chondroblasts
Cartilage matrix is composed of…
- ground substance
- extracelluar fibers
Composition of ground substance
- 70-80% water and proteoglycans
- chondronectin
A fibronectin-like substance, adherence of collagen of the surface of chondrocyte
chondronectin
Composition of extracellular fibers
a. collagen
b. elastic
Chondrogensis order:
mesenchymal cells > osteoprogenitor cells > chondroblasts > chondrocytes
Secrete the precursors of extracellular fibers (and other org constit.) in CM into intracellular area
chondroblasts
Young ___ possess mitotic and secretory capabilities, while mature ones are incapable of mitosis
chondrocytes
Growth of Cartilage
- interstitial (endogenous) growth
- appositional (exogenous) growth
Differentiate interstitial to appositional
interstitial
- expands the cartilage from within
- mitosis and secretions of young chondrocytes
- length and long bones
appositional
- function of perichondrium
Degeneration and regeneration of cartilage
- calcification of the matrix
- age
With age, the cartilage…
loses translucency and becomes opaque
Calcification of matrix…
- nutrition of cartilage is compromised
- one of the initial events in formation of some bones
Types of Cartilage
- hyaline
- elastic
- fibrous
Glistening, smooth, pearly white in fresh specimen
hyaline cartilage
What type of collagen does hyaline have?
type II collagen fibers
Most abundant cartilage type
hyaline cartilage
Hyaline is in which skeleton?
fetal skeleton
Hyaline is found in:
- epiphysial plate
- articular cartilage
- ears
- sternal end of the ribs
- trachea, bronchi, larynx, and nose
Yellowish and more flexible than hyaline
elastic cartilage
What type of collagen and fibers does elastic have?
type II collagen and elastic fibers
Less abundant matrix
elastic cartilage
Elastic cartilage is found in:
- auricle, external acoustic meatus, and auditory tube of ears
- epiglottis
- larynx
Withstand greater stress
fibrous cartilage
What are fibrous cartilage fibers made up of?
thicker type I collagen
Fibrous cartilage is transitional between…
cartilage to dense regular connective tissue