Cartilage and Bone

Cartilage and Bone
Objectives:
To be able to identify:
A. Hyaline cartilage, chondrocyte, lacuna,
isogenous group.
B. Haversian system( osteon), interstitial
lamella , bone lacuna, canaliculi.
loose connective tissue
connective
tissue proper
CT
dense connective tissue
adipose tissue
:
specialized
connective
tissue
reticular tissue
cartilage
bone
blood
Cartilage
chondrocytes
ground
Substance:
Cartilage
extracellular
matrix
rich in water,
glycosaminoglycans
and proteoglycans
Perichondrium
fibers
Fibrils
Hyaline Cartilage
Connective tissue
Elastic fibers
Elastic cartilage
Collagen fibers
protection
nourishment
essential for cartilage growth
Fibrocartilage
Hyaline Cartilage
Perichondrium
Cartilage
Perichondrium
Chondrocytes
Extracellular
matrix
Hyaline Cartilage
Chondrocytes
(be located in the
lacunae)
isogenous group
territorial matrix
interterritorial matrix
Where are the fibers?
Fibrils : is not visible in LM
Its refractive index is same as the ground substance
No.66
trachea
Pseudostratified ciliated columnar epithelium
epithelium
connective tissue
hyaline cartilage
Elastic cartilage
chondrocyte
elastic fiber
Perichondrium
Fibrocartilage
collagen fiber
chondrocytes
Elastic cartilage
Fibrocartilage
Hyaline cartilage
Summary of cartilage features
Features of
extracellular matrix
Location
Hyaline cartilage
Collagen fibrils
Fetal skeletal
tissue, articular
surface, trachea,
larynx...
Elastic cartilage
Type Ⅱ collagen
fibrils and
Elastic fibers
External ear,
epiglottis, auditory
tube
Fibrocartilage
collagen fibers
Intervertebral discs,
symphysis pubis,
articular discs,
tendon
Osseous tissue and bone
Osteoprogenitor cells: Stem cells
cells
Osteoblasts: synthesize collagen and ground substance;
be responsible for the calcification of the
matris
Osteocytes:
cell body--- in the lacuna.
Processes--- in the canaliculi
Osteoclasts: phagocytotic cells
Osseous
tissue
Be involved in the resorption and
remodeling of the bone tissue
collagen fibers
bone matrix
(Extracellular
matrix)
ground substance: GAG, glcoproteins
Calcium and phosphorus
Bone architecture
long bone
diaphyses (
)
(compact bone)
epiphyses (
)
(sponge bone)
Bone
osseous tissue
Sponge bone -----epiphysial portion
Compact bone----diaphysial portion
medullary cavity & bone marrow
periosteum & endosteum
Bone trabecula
Sponge bone
Compact bone
Sponge bone
Bone marrow Bone trabecula
Compact bone (diaphyses)
Out and inner circumferential lamellae
Circumferential lamellae
Osteon (Haversian system
Interstitial lamellae
)
Periosteum
Volkmann canals
Out circumferential
lamellae
Osteon
endosteum
Periosteum
Inner circumferenti
lamellae
No. 22
Osteon
Interstitial lamellae
Haversian
lamella
lacuna
central
canal
canaliculi
Haversian
lamella
lacuna
canaliculi
central
canal
Interstitial lamellae:
remanets of osteons
during
reconstruction.
I.L
os
bone lamella ：the form of bone matrix
bone lamella ：the form of bone matrix
Osteocyte
Be involved in the resorption and
remodeling of the bone tissue
Osteoclasts:
Osteoblasts:
synthesize collagen and ground
substance; be responsible
for the calcification of the
matrix
Bone growth
Intramembranous ossifcation
Endochondral ossification
Intramembranous ossifcation: skull, maxilla, mandible
Be replaced
Mesenchymal tissue
Mesenchymal tcell
Differentiate
Osteoblasts
Synthesis
Fibers, Ground Substance (osteoid )
Mineralization occour
bone
Endochondral ossification: long bone, pelvis, vertebrae
Model of long bone (formed by hyliane cartilage)
Be replaced progressively by bone
bone
Model of long bone (formed by hyliane cartilage)