exam 3 study guide

define osteoid

bone forming cells that secrete unmineralized bone matrix made up od collagen and calcium binding proteins

osteocytes

mature maintaining cells

osteoblasts

building cells

osteoclasts

destroy bone for remodeling

osteoprogenitor cells

stem cells that turn into osteoblasts and bone forming cells

what are the parts of compact bone

dense outer layer that appears smooth and solid, periosteum that covers the outside of compact bone and endosteum that covers inside portion of compact bone

appositional growth

cartilage forming cells in perichondrium that secrete matrix against external face of existing cartilage

interstitial growth

chondrocytes within the lacunae divide and secrete new matrix, which expands the cartilage within

how does interstitial growth affect the bone growth

since it takes place in the epiphyseal line, the bone increases in length

what role does epiphyseal cartilage play in bone growth

longitudinal growth of long bones

which hormones control the growth of bones

osteocalcin

which hormones control calcium homeostasis

parathyroid hormone, calcitonin, and vitamin D

which hormone increases blood calcium levels

parathyroid hormone

which organs produce hormones that control blood calcium levels

parathyroid gland in the thyroid

whats the first step in the process of intramembranous ossification

ossification centers are formed when mesenchymal cells cluster and become osteoblasts

whats the second step in the process of intramembranous ossification

osteoid is secreted then calcified

what is the third step in the process of intramembranous ossification

woven bone is formed when osteoid is laid down around blood vessels

what is the fourth step in the process of intramembranous ossification

lamellar bone replaces woven bone and red marrow appears

which bones form from endochondral ossification

all bones inferior to base of skull except clavicle

what is the relationship between bone and cartilage

cartilage is at the end of bones to reduce friction and prevent them from rubbing together when u use your joints

chemical components of bone

bone is made up of organic and inorganic compounds

½ as strong as steel when in resisting compression and soft organic allows for bones to resist tension

hydroxyapetite

mineral salt, makes up 65 percent of bone mass, in and around collagen fibers, calcium phosphate crystals, respnsibile for hardness

which nutirents are needed for bone

calcium, proteins, magnesium, vitamin d, potassium, phosphorus, and flouride

describe osteon

haversian system, structural unit of comapct bone. elongated ccylinder that run parallel to long axis of bone

what is the function of an osteon

acts as tiny weight bearing pillars

what is the 5 step in endochondral ossification

epiphyses ossify

what is the dfirst step of endochondrral

bony collar forms around diaphysis of cartilage model

what is the second step of endochondral

central cartilage in daiphysis calcifies then develops cavities

what is the 3rd step in endochondral

periosteal bud invades cavities leading to formation of spongy bone

wjat is the 4th step in endochondral

diaphysis elongates and medullary cavity forms

wolffs law

states that bones grow or remodel i response to the demands placed on them

hematopoiesis

formation of blood cellular compnents

joint

sites where 2 bones meet

fibrous joint

no joint cavity, synarthrotic, bones joined by dense fibrous CT

cartilaginous joint

bnes united by cartilage, amphiarthrotic, and no joint cavity

synovial joint

has a joint cavity, fluid filled, diarthrotic and in limb joints

what joint keeps gums in place

gomphosees

what are the types of fibrous joints

suturs, gomphoses, and syndesmoses

diarthrotic

movable

synarthrotic

immovable

amphiarthrotic

slightly movable

medial

roating towards midline

lateral

rotating away from meddial plane

flexion

decreasing angle between 2 bones usually in sagittal planes

extension

increasing angle between 2 bones

gliding

sliding the flat surface of 2 obnes across each other

circumduction

moving limb or finger so that it describes a cone space

which motion decreases

flexion

which motion increases

extension

jaw joints

hinge and gliding

feet joint

dorsiflexion, snd flexion

thumbs

oppostion

plsntsr flexion

toe pointing

dorsigflexion

moving foot upwsrds toward shin

luxation

full dislocation

subluxation

partial dislocation

whic motion damages knee ligaments

horizontal and lateral blows

which structure provides greatest stability of a joint

ligaments

why are hip joints more stable than shoulder joints

shoulder joints arent true ball and socket joints, the ball is bigger than the shallow socket

spien joint

facet joints h

head joints

tmj

which jounts ahve a gliding motion

intertarsals and intercarpals

nonaxial

gliding

unixaila

elbow, knee, ankle

biaxial

knuckle joint

multiaxial

shoulder and hip

parts of synovial joint

articular cartilage, synovil gluid, joint cavity, articular capsule, and nerves/blood vessels