Bone Tissue 1: Flashcards
Where does tissu hématopoïétique reside?
Inside the bones
This is the Red blood and White blood cell progenitors
What are the two components of the extracellular bone matrix?
La matrice organique (ostéoïde):
Fibres collagènes + Substance fondamentale
Mainly Type I collagen
La matrice minérale:
65% of all the MEC
Complexe d’ions et de sels minéraux: Calcium and Phosphate
This is what makes bone hard!!!
Which part of the ECM makes bone hard and what proportion does this take?
La matrice minérale:
65% of all the MEC
What are the main components of the La matrice minérale?
Complexe d’ions et de sels minéraux: Calcium and Phosphate
What is the main content of La matrice organique ?
Fibre collagen type I
What are the 5 cells of bone tissue?
ostéogéniques
osteoblaste
osteocytes
cellules bordantes
osteoclaste
What are the only bone cells capable of diving?
cellules ostéogeniques
Wher edo you find cellules ostéogeniques in bone?
dans la couche interne du périoste
de l’endoste
sur les parois des canaux de Havers
What are perioste and endoste?
Kinda like perichondre for cartilage
they line the outside and iside of bone
True or False, Osteoblasts will divide to give osteocytes.
FALSE.
Osteoblasts are cellules différenciées qui ne se divisent plus
What cell is responsible for the secretion of ECM in bone?
Osteoblasts
What cell is responsible for the mineralization of bone?
Osteoblasts
What are cellules bordante and what is their main role?
At rest Osteoblasts
Ne se divisent pas
Ostéoblastes en repos, elles reprennent leur activité au besoin
Protection contre la dégradation de la MEC, régulation du Ca++ et de la nutrition de l’os
How are osteocytes formed?
Osteoblasts release bone material, imprison themselves becoming osteocytes
What are vésicules matricielles?
Released by ostéoblastes
contiennent beaucoup de
calcium et une variété
d’enzymes qui génèrent le
phosphate, ce qui va aboutir
à formation des foyers de
minéralisation
What is the role of osteocytes?
Renouvellement et maintenance de la MEC
Remodelage osseux (en sécrétant de
l’acide citrique, de la phosphatase acide,
des enzymes protéolytiques et des
peptidases).
What is Lacune de Howship?
Formed by the bone breaking process of ostéoclastes
True or False, Osteoclasts travel from blood vessels and have a singular nuclei.
FALSE
How do osteoclasts break bone?
Starts by breaking mineral tissue:
Through acidification
Phagocytic activity
Bone reabsorption
What are the two possible bone morphology stuctures?
Couche externe rigide, l’os compact (os cortical):
Os spongieux (os trabéculaire):
Structure important to lower bone weight.
Includes moelle hématopoïétique → Bone marrow.
Can also find moelle osseuse jaune → Adipose tissue.
With age moelle osseuse jaune is increased.
What is moelle osseuse jaune?
Adipose tissue inside the Os spongieux.
With age moelle osseuse jaune is increased.
What are the three possible bone morphology based on shape?
Os long
Os Court
Ost Plat
What are the parts of os long and their properties?
Diaphyse :
contains the cavité médullaire in the inside
composed of compact bone on the outside
Épiphyse:
Made of os spongieux in the center
Limited between the diaphyse by the cartilage de conjugaison fill later
Does not have os compact on the outside but rather cartilage articulaire
Metaphyse
What is metaphyse?
It is the Zone de la croissance de l’os: Métaphyses
What bone does this describe:
Os spongieux + 2 couches d’os compact revêtues par un périoste
Os plat
What bone does this describe: Os spongieux entouré d’un os compact
Os court
What covers the outside of compact bone?
le périoste
What are Sharpey fibers?
Le périoste est solidement
attaché à l’os grâce à des
faisceaux de collagène qui
s’enfoncent dans les lamelles
circonférentielles externes de l’os
appelés: les fibres de Sharpey.
What is Le tissu osseux non-lamellaire?
primary; non-mature bone; only present in fetus
Collagen Fibers are not oriented on the same direction.
True of False, Le tissu osseux lamellaire is found only in compact bone tissue
False.
Can be compact ou spongieux
True of False, Le tissu osseux non-lamellaire is found only in compact bone tissue
False.
Can be compact ou spongieux
What is the difference between Le tissu osseux non and -lamellaire in terms of Ostéocytes?
Ostéocytes régulièrement répartis entre les
lamelles
What are the three types of Lamellar Bone?
L’os lamellaire compact Haversien
L’os lamellaire compact non-Haversien
L’os lamellaire spongieux ou trabeculaire
What do we find in the canal de havers?
Canal de Havers: capillaires sanguins + fibres nerveuses
And on the around we have osteoblasts
What connects two canal de havers?
canal de Volkman.
What do we find between the lamelle of an osteon?
ostéocytes
What is the role of L’os lamellaire compact non-Haversien?
It is the Le système circonférentiel → The connection of système Havers to périoste and endoste.
It is what separates l’os Haversien de l’endoste et du périoste
What is Système interstitiel?
Because the bone is in continuous breakage and rebuild, we find between osteons this system of incomplete osteons:
Système interstitiel
TRUE OR FALSE, we can find os haveresien (osteons) in both spongeous and compact bone/
FALSE.
Osteons only in compact bone
You can find L’os lamellaire spongieux ou trabéculaire in spongeous bone
Where do we find L’os lamellaire spongieux ou trabéculaire?
L’os du diploë des os plats, les os courts, les
épiphyses et les métaphyses des os longs
The spongieus bone
How can spongious bone be lamellare?
Les lamelles de l’os spongieux ne sont pas circulaires, mais plutôt parallèles à la surface des travées
