Cartilage bone and articulations Flashcards
diaphysis
the shaft of the bone
epiphysis
the end of the bone
metaphysis
the narrow region where the diaphysis connects to the epiphysis
cartilage
- this is primarily made of water
- avascular
- gets nutrients from diffusion
chondroblasts
cartilage building cells
chondrocyte
mature cartilage cell
perichondrium
-this is the outer layer of cartilage that resists outward pressure
hyaline cartilage
- the most common type of cartilage
- provides stiff but somewhat flexible support
- contains closely packed collagen fibers
where can hyaline cartilage be found
- between the tips of the ribs and the sternum
- covers bone surfaces at synovial joint
- supports the laynx, trachea, bronchi
elastic cartilage
provides support but tolerates distortion
- contains elastic fibers
where is elastic cartilage found
this is found at the external ear, the epiglottis, the auditory canal
fibrous cartilage
- contains dense collagen fibers that resist compression
- can sometimes lack pericardium
- prevents bone to bone contact
where can fibrous cartilage be found
-this is found in the pads of the knee joint, between pubic bones, intervertebral discs
describe what makes up bone tissue
- it is 35% organic components (collagen fibers, ground substance)
- it is 65% inorganic compounds like mineral salts that invade the bony matrix
- together it makes a strong yet flexible combination that is resistent to shattering
osteogenic cells
these are the stem cells that turn into osteoblasts
osteoblasts
these are the builders of the bone
osteoclasts
these break down the bone for remodeling or to harvest calcium
-these have multiple nuclei
osteocyte
this is a mature osteoblast
-these are responsible for the maintence and turnover of mineral content surrounding bones
compact bone
- covers the surface of all bones
- the thickness depends on the amount of stresses that occur there
osteon
- this is the functional unit of the compact bone
- it has osteocytes arranged in circular layers around the central canal
central canal of osteon
- this is where blood vessels are contained
- these run parallel to the surface of the bone
concentric lamellae
the cylindrical rings around the central canal
interstitial lamellae
- these fill in the spaces between the osteons
lacunae
small chambers that the osteocytes live in
circumferential lamellae
these occur at the external and interstitial surfaces of the bone
canaliculi
the channels that connect lacunae together with each other and to the central canal that allow nutrients to pass through
perforating canals
passageways within compact bone that extend perpendicular to the surface
-blood vessels in these deliver blood to the osteons deep in the bone and service the medullary cavity
marrow
this is a loose connective tissue within the medullary cavity
red marrow
a mixture of mature and immature RBC and WBC
- important sites of cell formation
- in some spongy bone of adults and medullary cavity in children
yellow marrow
dominated by adipocytes
- this is an important energy reserve
- this is in the diaphysis in the medullary cavity
appositional growth
- increases the diameter of cartilage and bone
- this happens within bone throughout life (not cartilage)
trabeculae
layers of parallel lamellae and osteocytes
-these are in spongy bone
periosterm
fibrous outter layer and inner cellular layer that surrounds all bones (except joints) that aids in the attachments of surrounding tissues/ligaments/tendons
-the inner cellular layer is important for bone growth
bony prominance
something that sticks out of the bone for attachment purposes
-attachment causes pulling on the bone so it grows in that direction
articular surface
where they make a joint with another bone
depressions
these are where things are traveling along a bone ( maybe a nerve or a blood vessel)
functions of bones:
- support
- movement
- protection
- mineral storage
- hematopoisis
- energy metabolism
spongy bone
arranged in paralle thick branching plates called trabeculae
- there are lots of holes in these spaces
- make the overall weight of the skeleton lighter
- resists stresses from multiple directions
endosteum
-an incomplete cellular lining found on the inner surfaces of the bone that lines the medullary cavity
what are the four major blood supply to bones
- nutrient artery and vein
- metaphyseal arteries and veins
- epiphyseal arteries and viens
- periosteal arteries and veins
ossification
also known as osteogenesis
-bone formation
intramembranous ossification
bones formed directly from a membrane of connective tissue
-this is the formation of flat bones
flat bones
skull, mandible, some facial bones scapula, clavicle
endochondral ossification
- develop from hyaline cartilage
- this is what the rest of the bones in the body develop from
- this begins in the 8-12th week of embryonic development and continues froming into early development
steps of intramembranous ossification
- the stem cells of the mesenchyme (embryonic tissue) differentiate into osteoblasts and secrete matrix (turns into ossification centers)
- formation of bony spicules (they are reaching out from the ossification sites and they are pulling them together, forming larger ossification sites)
- entrapment of blood vessels (important for nutrients being provided to the cells
- formation of spongy bone
mesenchyme
a tissue or clustering of cells that is originating from the embryonic development