bones Flashcards
how many bones does have a new-born have ?
300 soft bone
how many bone does a adult have ?
206 bones
what 2 things make up the skeletal system ?
bones+cartliages
name the 5 types of bones?
-long
-flat
-irregular
-short
-sesamoid
name the 3 parts of the macroscopic anatomy of the long bone ?
-diaphysis
-epiphysis
- metaphysis
define diaphysis ?
shaft of the bone
define epiphysis ?
proximal and distal ends of the bone
define metaphysis ?
between the diaphysis and the epiphysis
where does the articular cartilage cover ?
covers the epiphysis, for example there is AC of the femoral condyles.
define periosteum ?
surrounds the external bone surface
define endosteum
thin membrane that lines surface of medullary cavity(hollow part inside of bone) inside of bone
what are the 2 parts of the microscopic bone anatomy ?
- compact bone
- cancellous bone
define the cancellous bone ?
inside the compact bone (SPONGY) reduces overall weight of bone, supports and protects red bone marrow.
define the compact bone ?
protection and support, resists the stresses of movement and weight.
where is compact bone found ?
found below the periosteum
what makes up the bulk of the diaphysis ?
compact bone
what is the compact bone made off? (hint-o….)
osteons, microscopic cylinders
what is within osteons ?
osteocytes. this is surrounded by a matrix of minerals and fibres
what is a harversian ?
sits within centre of osteon, has arteries, veins, nerve fibre
what do osteons also contain?
osteons also contain collagen and lamelle
describe the microscopic anatomy of cancellous bone?
-Cancellous bone (spongy) – refers to appearance not its texture
-Does not contain osteons
-consists of an irregular lattice of thin columns – trabeculae
- spaces between trabeculae’s makes bone lighter, also contains bone marrow.
what do Osteogenic/osteoprogenitor cells
do ?
and where are they found?
hint; before osteoblasts, what are all cells initially ?
found inner layer of … and ….
-Unspecialised stem cells, before osteoblasts
-Location: inner layer of the periosteum, the endosteum
what do osteoblasts do ?
and where are they found ?
hint; Sytheseisie osteoid and … to form hydro….
found on all ….
-Bone building cells, synthesise enzyme and osteoid required to form hydroxyapatite
Location: on all bone surfaces
what do Osteocytes do ?
and where are they found ?
hint : you have a fast one or slow one
maintains … exchange
found in … of compact and cancellous bone ?
-Mature osteoblasts
Maintain daily metabolism and nutrient/gas exchange
-Location: in the lacunae of compact and cancellous bone