EXAM 2 Flashcards
what is the diaphysis
long shaft or body of bone
what is the epiphysis
proximal and distal ends of a bone
what is the metaphysis
region between the diaphysis and epiphysis
where are the epiphysial plates found
in the metaphysis
what is the name of the cartilage that covers the epiphysis at joints.
articular cartilage
what is the periosteum
tough connective tissue sheath that surrounds the bones.
What are the two layers of the periosteum
- outer fibrous layer
2. inner osteogenic layers
what is the medullary cavity
hollow, cylindrical space in the bone that hold yellow marrow
what is the endosteum
thin membrane that lines the medullary cavity
what two chemicals make up hydroxyapatite
calcium phosphate + calcium hydroxide
how do bones calcify
minerals calcify around collagen fibers
what type of strength does collagen fibers provide
tensile strength
what are osteogenic cells
unspecialized bone cells derived from mesenchyme.
What type of cells to osteogenic cells specialize intio
osteoblasts
what are osteoblasts
bone building cells, synthesize and secrete collagen fibers and minerals to build ECM.
what type of cells to do osteoblasts become
osteocytes
what are osteocytes
mature bone cells, main cells in bone tissue and help maintain tis normal metabolism.
what are osteoclasts
break done bone cells, found in endosteum
what is is stronger spongy bone or compact bone
compact bone
what is the structural unit of compact bone
osteon
what are concentric lamellae
circular plates of ECM, run parallel to the bone
what are lacunae
small spaces between the concentric lamellae
what are canaliculi
fingerlike projections of osteocytes
does spongy bone contain osteons
no
what are the web like projections found in spongy bone
trabeculae
what bones are mostly made up of spongy bone tissue
short, flat, sesamoid, and irregular bones
in what type of bone formation does the bone form directly from the mesenchyme
intramembranous ossification
what part of the body is mostly made through intra ossification
the skull
what happens during “the development of ossification center” (IM)
at site where bones develop, mesenchyme cells cluster and differentiate first into osteoprogenitor cells and then into osteoblasts.
what happens in calcification (IM)
secretion of ECM stops. Osteocytes lie in lacunae that spread into cuniculi. Ca and other minerals are deposited calcifying the ECM.
what happens in formation of trabeculae (IM)
form trabeculae and red bone marrow
what happens in development of periosteum (IM)
mesenchyme condenses at periphery of bone and forms periosteum
what is endochondral ossification
replacement of cartilage by bone
what types of bones are formed by ECO
most of the bones in the body
What happens in development of cartilage model
mesenchyme crowds together to form shape of future bone and develop into chondroblasts. Chondroblasts secret cartilage ECM and make cartilage model made of hyaline cartilage.
interstitial growth grows in which direction
lengthwise
appositional growth grows in which direction
widthwise
what happens in development of primary ossification center
proceeds inward from external surface of bone, nutrient artery penetrates the perichondrium thru a nutrient foramen, stimulating osteoprogenitor cells in the perichondrium to differentiate into osteoblasts. primary ossification center forms and spreads towards the ends of the bones.
Development of medullary cavity
osteoclasts break down spongy bone in center and forms medullary cavity.
development of secondary ossification center
occurs in the epiphyses of bones. Proceeds outward rather than inwards. no medullary cavity.
formation of articular cartilage and growth plate
hyaline cartilage that surrounds outside of epiphysis turns into articular cartilage
growth in length of a bone
growth of cartilage on epiphysial side of epiphysis, replacement of cartilage by bone of diaphyseal side of cartilage by endochondral ossification.
what is the order of cartilage in epiphyseal plate
- zone of resting cartilage
- zone of proliferating cartilage
- zone of hypertrophic cartilage
- zone of calcified cartilage
zone of resting cartilage
most upper level, small scattered chondrocytes
zone of proliferating cartilage
larger chondrocytes stacked like coins, divide to replace dead chondrocytes below.
zone of hypertrophic cartilage
large chondrocytes arranged in columns
zone of calcified cartilage
few cells thick, dead chondrocytes, osteocytes dissolve calcified cartilage and osteoblasts go in and create bone.
when finished growing what does the epiphyseal plate become
epiphyseal line
what are the three types of joints that are classified by structure
- fibrous
- cartilaginous
- synovial
what are the three joints classified by mobility
- synarthrosis
- amphiarthrosis
- diarthrosis
which joint is immovable
synarthrosis
what type of joint is slightly moveable
amphiarthrosis
what type of joint is freely moveable
diarthrosis
three types of synarthrosis
- suture
- gomphosis
- synchondrosis
three types of amphiarthroses
- syndemosis
- interosseous membrane
- symphosis
all diarthrosis are what type of joint
synovial
types of diarthrosis
- gliding joint
- hinge joint
- pivot joint
- condyloid joint
- saddle joint
- ball and socket joint
reactive phase of fractures
fracture hematoma forms, osteoclasts dissolve dead bone tissue
reparative phase pt 1 of fractures
fibrocartilaginous callus forms it is made up of collagen fibers that bridge broken pieces.
reparative phase pt 2 of fractures
fibrocartilaginous callus turns into spongy bone by osteoblasts. Now it is called the bony callus.
Bone remodeling phase of fractures
bony callus turns into real bone, and compact bone forms periphery.
Which hormone increases blood Ca levels
parathyroid hormone
which hormone decreases blood Ca levels
calcitonin
what is rickets
child disease that results in soft and rubbery bones
what is osteomalacia
adult counterpart of rickets results from inadequate calcification of extracellular bone matrix.
two types of arthritis
osteoarthritis and rheumatoid arthritis
what is bone modeling
construction, bone formed by osteoblasts without prior resorption
bone remodeling
occurs when bone is resorped by osteoclasts and rebuilt by osteoblasts
what are the organic compounds of bone ecm
ground substance and collagen fibers type 1
what are the inorganic components of bone ecm
water and hydroxy apatite
outer layer of periosteum has what
dense irregular tissue
inner layer of periosteum contains
inner osteogenic layer
what is the top bone of sternum called
manubrium
middle part of the sternum is called what
the body
the lower bone of the sternum is called what
xyphoid process
how many pairs of true ribs are there
7
which ribs are false ribs
8-12
which ribs are floating ribs
11 and 12
what is the active form of vitamin d
calcitriol
where is calcitrol made
the kidneys
what does calcitriol do
increases blood Ca levels
