Bones & skeletal sys Flashcards
Intra-
within
meso-
middle
os- / osteo-
bone
peri-
around
-blast
create
-clast
break down
-cyte
a cell
chondro-
cartilage
4 tissue types of skeletal system
bones, cartilage, ligament, tendon
6 major functions of skeletal system
- support
- protection
- assistance w/ movement
- mineral homeostasis
- produce blood cells
- store triglyceride (energy)
a-
not / none
2 ways cartilage grows
- Appositional: cartilage added to outside of existing cartilage
- Interstitial: chondrocytes (in matrix) divide & add more matrix b/w chondrocytes
lacunae
small spaces where chondrocytes lie
acellular matrix of cartilage consist of…
dense network of collagen & elastic fibres, and chondrocytes w/in lacunae
how is cartilage made?
chondroblasts produce matrix => once surrounded by matrix changes name to chondrocytes (located in lacunae)
bone matrix includes
(35%) organic [collagen & proteoglycan] & (65%) inorganic [hydropyapatite]
Formation of bone matrix by…
ostification/osteogenesis from osteoblast. Osteoblast (E.R & golgi) produce & release collagen. Precursors of hydroxyapatite (in vesicles) released
2 ways bone grows
1st. Woven: collagen fibres randomly arranged (foetal develop. & initial fracture repair)
2nd. Lamellar: woven bone is broken down by osteoclast & reformed into lamellae (thin sheets). Each lamellae has collagen fibres parallel to each other, but in different lamellae CF at diff. directions
2 Types of bone formation (ossification)
- Intramembranous: w/in CT membranes e.g. skull bones
2. Endochondral: w/in cartilage template e.g. base of skull
4 classification of bones according to shape
- long: upper & lower limbs
- Short: carpal (wrist) & tarsals
- Flat: ribs, sternum, skull, scapul
- Irregular: vertebrae, facial
2 types of bone
- Spongy/cancellous/trabecular: pores (trabecullae).»_space; weight bearing
- Compact/Cortical: contain osteon/Haversian sys.
Describe structure of osteon in compact bone
- central/haversian canal
- Lammellae: circumfrential (around central canal) & interstitial (in b/w osteons)
- Perforating/Volkmann’s canal: small horizontal canal - transmit blood vessels from periosteum to haversian canal
types of bone structures
- Flat: no diaphysis & epiphysis. Sandwich of spongey & compact bone (skull, ribs, sternum)
- short & irregular: compact bone surrounding spongey bone (like epiphysis). No diaphysis (vertebrae, carpals, tarsals)
- has Long: epiphysis, diaphysis, medullary cavity, epiphyseal plate (hyaline cartilage) /line (kids/adults). (e.g bones of limbs)
Blood Calcium homeostasis
- Low levels: PTH stimulates osteoclast to break bone
- Hi levels: Calcitonin (from parafollicular cells in Thyroid gland) decreases osteoclast activity. & osteoblast make new bone
why are Ca2+ needed by the body?
- release neurotransmitters
- muscle contraction
- blood clotting (enzyme cofactor)
bone formation marker
osteocalcin (hormone secreted by osteoblast) promotes insulin secretion & improves insulin sensitivity & testosterone production
what are the areas of bone that allow for smooth articulation?
Condyle: smooth rounded articular surface
& facet: small flattened articular surface
3 Major classifications of joints & its sub groups.
- Fibrous = non-moveable.
- Cartilaginous = slightly moveable. hyaline
- Synovial = freely moveable
Characteristics & subclassification of Fibrous joints
Unite 2 bones w/ Fibrous CT, no joint cavity, little/no movement. Gomphosis (teeth joints), Sutures, syndesmosis (radioulnar)
Characteristics & subclassification of cartilaginous joints
unite 2 bones w/ cartilage, little/no movement, permanent/replaced by synchondrosis. Hyaline CJ (epiphyseal plate), fibrocartilage J (symphysis pubis, intervertebral discs)
Characteristics & features of synovial joints
contain synovial fluid, complex joints, moveable. Most joints unite appendicular skeleton & greater mobility than axial
angular movements
- flexion: bend anteriorly from coronal plane
- extension: straighten/bend posteriorly to coronal plane
* except w/ knee - FOOT: dorsiflexion (up) and plantar flexion (down)
- Abduction
- Adduction
Circular movements
- Medial & lateral Rotation
- Pronanation & supination
- circumduction
special pair movements
- elevation (up) & depression (down shoulders) *shoulder joints can’t
- protraction (underbite) & retraction (overbite)
- Inversion (tilt foot -> midline) & eversion (rotate away midline)
- Opposition (touch fingertips w/ thumb) & reposition (relax to normal)
tronchanter
large projection
tuberosity
rounded projection
fossa
shallow depression
Foramen
opening
Crest
prominent ridge
process
prominent projection
meatus
passageway
Head
enlarged & rounded end
neck
b/w head and body
condyle
large rounded protuberance (bone protrudes from bone)
fissure
narrow slit
