bones 🦴 Flashcards
human skeleton initially consists of _ ?
cartilage
the cartilage gets replaced by _ ?
bone, except where flexibility is needed
types of cartilage
hyaline
elastic
fibrocartilage
what type of cartilage…
- provides support, flexibility, and resilience
- most abundant
- fibers: collagen
- location: joints, costal cartilage, larynx, nasal cartilage
HYALINE
what type of cartilage…
- provides elasticity
- fibers: elastic
- location: external ear and epiglottis
ELASTIC
what type of cartilage…
- provides tensile strength
- fibers: collagen
- location: menisci of knee and vertebral discs
FIBROCARTILAGE
protection is for…
protect brain, spinal cord, and vital organs
bone functions
support
protection
movement
mineral and growth factor storage
blood cell formation
triglyceride storage
hormone production
support is for…
body and soft organs
movement is for…
levers for muscle action
mineral and growth factor storage is for…
calcium and phosphorus
blood cell formation is for…
hematopoiesis, red marrow
triglyceride storage is for…
fat, used for energy source, yellow marrow
hormone production is for…
osteocalcin secreted by bones helps to regulate insulin secretion, glucose levels, and metabolism
total # of bones in the body
206
location classifications
axial
appendicular
long axis of body
ex: skull, vertebral column, rib cage
axial
bones of upper and lower limbs
ex: girdles attaching limbs to axial skeleton
appendicular
shape classifications
long
short
flat
irregular
longer than they are wide
ex: limb bones
long bones
cube-shaped bones (wrist and ankle)
ex: sesamoid bones (patella)
short bones
thin, flat, slightly curved
ex: sternum, scapulae, ribs, skull bones
flat bones
complicated shape
ex: vertebrae and hip bones
irregular bones
what tissues make bones an organ
bone
nervous
cartilage
fibrous connective
muscle cells
epithelial cells
3 levels of structure
gross
microscopic
chemical
dense outer layer appears smooth and solid
compact bone
honeycomb are small needle like flat spaces
Trabeculae
open spaces are filled with red or yellow marrow
spongy
shaft
consists of compact bone surrounding central medullar cavity filled with yellow marrow in adults
diaphysis
ends
external compact
internal spongy
articular cartilage covers the joint
epiphyseal line/plate
epiphysis
White double layered
Covers external surfaces except joints
Contains nerve fibers and blood vessels
Anchors tendons and ligaments
Has osteogenic cells
periosteum
Covers internal bone surface
Covers trabeculae of spongy bone
Lines canals that pass through compact bone and has osteogenic cells
endosteum
found in cavities of spongy bone
newborns also found in medullary cavities
in adults it is found in the dipole of flat bones - sternum - heads of femur and humerus
most active area - HIPS
red marrow
-mitotically active and found in periostium and endosteum
-differentiates into osteoblasts, bone-lining cells, some remain osteogenic stem cells
osteogenic
(aka osteoprogenitor cells)
-bone forming cells that deposit unmineralized bone matrix called osteoid which is made up of collagen and calcium binding proteins.
-are actively mitotic
osteoblasts
collagen makes up ____% of bone protein
90%
-mature cells in lacunae
-do not divide
-respond to mechanical stimuli
-communicate info. with osteoblasts and osteoclasts
osteocytes
help maintain matrix
bone-lining cells
derived from hematopoietic stem cells that become macrophages
function in bone reassign calcium, bone resorption.
osteoclasts
compact bone = ?
lamellar bone
compact bone consists of ?
osteon (haversian system)
canals and canaliculi -> supply blood and nutrients
interstitial and circumferential lamellae -> rings -> network for matrix
organized along lines of stress
trabeculae give strength
no osteons are present
capillaries supply nutrients
spongy bone
ends out of normal alignment after fracture
Displaced
normal position after fracture
Non-displaced
broken all the way
Complete
not broken all the way
Incomplete
skin is not penetrated
Simple - closed
skin is penetrated
Compound - open
bone fragments into three or more pieces
comminuted
bone is crushed
compression
ragged break caused by twisting forces applied to bone
spiral
epiphysis separates from the diaphysis along the epiphyseal plate
Epiphyseal
broken bone pressed inward
most commonly occurs in skull
Depressed
incomplete fracture – twig breaking – one side breaks, one side bends
greenstick
4 major stages of bone repair
a. Hematoma formation
b. Fibrocartilage callus
c. Bony callus
d. Remodel
growth usually stops during
adolescence
females age ?
18
males age ?
21
grows in thickness
throughout entire life
in response to muscle activity or added weight
What is hematopoiesis?
blood cell production
calcium roles in the body
nerve transmission
muscle contraction -> heart
blood coagulation
cell division
too much growth hormone = ?
giantism
what stimulates the epiphyseal plate activity
growth hormone
what hormone regulates growth hormone
thyroid hormone
too little growth hormone = ?
dwarfism
