Bismillahirahmanirrahim
OK.. now I'll share about 'Cartilage' in our body =)
Cartilage arise from mesenchymal. It consist of :
1. Cell (Chondrocyte & Chondroblast)
2.Connective tissue
3. Ground substance (Non vascular. Got nutrient from diffusion)
There are 3 types of cartilage :
1. Hyaline cartilage
2. Elastic cartilage
3. Fibro cartilage
Hyaline and elastic cartilage were covered by 'perichondrium'.
Perichondrium consist of 2 layers.
1. Outer : vascular connective tissue + type I collagen
Perichondrium consist of 2 layers.
1. Outer : vascular connective tissue + type I collagen
2. Inner : chondrogenic that give rise to chondroblast (that secrete cartilage matrix)
Cartilage matrix produce and maintain chondrocyte & chondroblast. Contain large aggregate of proteoglycan and highly hydrated.
Mature cell for cartilage : Chondrocyte (enclose in lacunae)
"Hyaline cartilage"
* Most common : serve skeletal muscle
* Can be replace by bone during endochondral ossification
*Contain type II collagen
*Can be found :
(TEN BeBaL)
T- Trachea
E-End of Ribs
N- Nose
B-Bronchi
B-Bone
L-Larynx
"Elastic cartilage"
*For structural support & increase flexibility
*Contain : elastic fibre in matrix & highly flexible
* Found in :
(EEA)
(EEA)
E-External ear
E-Epiglottis
A-Auditory tube
" Fibro cartilage"
*Dense bundle of type I collagen
*Function:
(TBR)
T-Tensile strength
B- Bear weight
R- Resist compression
*Found in :
-Invertebral disc
-Certain joint
-symphysis pubis
"Bone"
Picture above shows 'compact bone'
Info based on picture :
- In compact bone, collagen fibre arranged in lamellae
- Deep to periosteum is circumferential lamellae
-Lamellae surrounding bone marrow
-Osteon also exist and known got 'Haversian system'.
-Between Harversian system : central canal
Bone matrix :
-Highly vascularized (calcified diffusion)
-Major component : Collagen fibre
-Glycoprotein component bind to calcium (mineraliztaion)
Bone usually continually remodal those thing :
1. mineral needs
2. Mechanical stress
3. Thinning/disease
There are 2 hormone involve in this :
1.Thyroid :- Inhibit action of osteocyte. Thus, decrease the bone re-absorption.
2.Parathyroid hormone :- Stimulate osteocyte. Increase bone reabsorption and release calcium into blood.
Okay.. Now, lets talk about 'cell in bone'
Basically, we need to know 3 things :
1. Osteoprogenitor cell that located in :
(PEOP)
P-Periosteum
E-Endosteum
O-Osteon
P-Perforating canal
2. Osteoblast :
-It's on bone surface
-Synthesized bone matrix
3. Osteocyte :
-mature cell of osteoblast
- Branch located in lacunae
-Use canaliculi for communication and exchange
-maintain bone & blood homeostasis in terms of calcium and phosphate
Ok.. I hope you enjoying this :)