Cartilage and Bone Flashcards
What are the three types of cartilage
Hyaline, Elastic, Fibrocartilage
What type of fiber is in hyaline cartilage
type 2 collagen
What type of fiber is in elastic cartilage
type 2 collagen plus elastic fibers
What type of fiber is in fibrocartilage
type 1 collagen
Where can you find elastic cartilage
Head area: ear, epiglottis, laryngeal cartilages, pharyngo-tympanic tubes
Where is hylaine cartilage
It is most abundant
nose, upper respiratory passages, costal cartilages, articular cartilages in legs
Where is fibrocartilage
Intervertebral discs, Pubis symphis, meniscus of knee, insertion of achilees tendon
What is the perichondrium? what are the two layers
layer of dense irregular ct that surrounds catrilage of developing bone. fibrous and chondrogenic layers.
What do chondroblasts do
Make cartilage matric
What are chondrocytes
The mature cells in lacunae of matrix that have differentiated from perichondrium
What are the two kinds of chondrocyte growth in cartilage
appositional or interstitial
what is interstitial growth
division of preexsisting chondrocytes.
what is appositional growth
from the differnetiation of chondrogenic cells in perichondrium
what are isogenous groups
deep groups of 4-8 chondrocytes that are all from a single progenitor cell formed by interstitial growth
What differentiates elastic cartilage from hyaline cartialge
Is like hyaline but also has elastic fibers. looks yellowish color
Which of the cartilages have a visible perichondrium
Elastic and hyaline not fibrocartilage
What is in bone matrix
Osteoid- (35% of weight) type 1 collagen, PGs, GAGs (chondrotin and keratan sulfate)
Hydroxyapetite- (65% of weight) calcium which mineralizes it, making it hard
Applied pressure vs applied tension
applied pressure leads to bone resorption, applied tension leads to bone formation
What is the periosteum
noncalcified membrane that is on outer surface of all bones except joint of long bones
what lines the inside marrow cavities
endosteum
What do osteoblasts make? Where are they located?
Make osteoid (organic components) and deposit inorganic components. On the surface of the bone tissue.
Made from osteoprogenitor cells
Where are osteocytes located? What is there function
THey are derived from osteoblasts. they sit in lacuna surrounded by bone matrix and help maintain bone matrix
how do osteocytes connect to other osteocytes
via gap junctions between cyoplasmic process in canaliculi
Are osteoclasts small? mobile?
Big and mobile.
DO osteocytes have multiple nuclei or one
Mulitple
What is the border between an osteoclast and matrix
RUffled border where enzymes are secreted
What is the Howship’s lacuna
bone pits formed by the enzymes released by osteoclasrs
What molecule is released by osteocytes
Carbanoic anhydrase which releases H+ to help break down hydroxyappetite.
Osteoperosis
Estrogen dependent decline in osteoblast activity
Rickets
Osteomalacia, disturbance in bone mineralizations due to lack of calcium or vitamin d. can’t take up calcium without vitamin d
Osteosarcoma
malignant tumorderived form osteoblasts (more common in children) seen in the bones around the knee joint but can metastasize quickly.
What is the difference between the Haversian and Volkmanns canal
Haversian are verticle with nutrients
Volkmanns transverse across long axis.
Intramembranous bone formation
For flat bones. Mesenchymal condensation
What is the type of bone formation for long and short bones
Endochondral bone formation
-hyaline cartilage model
Where is the primary center of ossification for Endochondral bone formation
Mid of diaphysis
Where is the secondary center of ossification for Endochondral bone formation
In epiphyses. Add cartilage at epihyseal emd and replace with bone on diaphyseal end.
What is in the zone of reserve cartilage?
In epiphyseal plate it is the epiphyseal side of the plate. has random inactive chondrocytes.
What is the zone of proliferation
chondrocyte proliferation- rapid mitotic division
what is the zone of hypertrophy
chondrocytes enlarge
what is the zone of calcified matrix
chondrocytes die and cartilage calcified.
what is the zone of ossification
osteoblasts elaborate bone matrix on calcified cartilage. makes calcified cartilage- calcified bone complex which is resorbed and replaced by bone.
