Chapter 7: Bone Tissue Flashcards
__ &__ are the most durable remains of a once living body?
bone & teeth
osteology
study of bone
What is the skeletal system composed of?
bone, cartilage, & ligaments
cartilage
precursor to bone
ligament
hold bones together at the joints
tendons
attach muscle to bone
What are the functions of the skeletal system? (6)
- support
- protection
- movement
- electrolyte balance
- acid/base balance
- blood formation
Flat bone
thin; protects soft organs
Long bone
longer than wide; acted upon muscles
Short bone (2)
- equal in length & width
- glide across one another in multiple directions
irregular bones
elaborate shapes that do not fit into any of the other categories
compact bone (2)
- outer shell of long bone
- makes up 3/4 of bone weight
diaphysis
shaft; cylinder compact bone to provide leverage
medullary cavity
space in the diaphysis of long bone that contains bone marrow
epiphyses
enlarged ends of long bone (strengthen attachment)
spongy bone (2)
- covered by durable compact bone
- makes up 1/4 of bone weight
articular cartilage (3)
- made up of hyaline cartilage
- covers the joint surfaces where one bone meets another
- allows for free movement of joints
nutrient foramina
minute holes in the bone surface that allows blood vessels to penetrate
periosteum
external sheath that covers the bone except where there is articular cartilage
what part of the periosteum is important to growth of bone & healing of fractures
inner osteogenic layer
endosteum
thin layer of reticular connective tissue lining marrow cavity
epiphyseal plate (3)
- area of hyaline cartilage that separates the marrow spaces of the epiphysis & diaphysis
- growth plate
- enables growth in length
Construction of flat bone (2)
- sandwich like structure: spongy bone in between compact bone (2)
- both surfaces of flat bone covered with periosteum
_____ is a type of joint
suture
diploe
spongy layer in cranium that absorbs shock
bone is connective tissue that consists of ___, ____, and _____
cells, fibers, and ground substance (made up of matrix)
What are the 4 types of bone cells?
osteogenic, osteoblast, osteocytes, & osteoclasts
osteogenic (osteroprogenitor) cells (3)
- stem cells found in endosteum, periosteum, & central canals
- undergoes mitosis
- arise from embryonic mesenchymal cells
What do osteogenic cells produce?
osteroblasts
osteoblast (3)
- nonmitotic
- lined up as single layer under endosteum & periosteum
- synthesize soft organic matter of matrix
What stimulates osteogenic cells to multiply more rapidly? What does this increase?
stress & fracture; osteocytes to rebuild bone
What is secreted by osteoblasts?What is it thought to be?
osteocalcin: thought to be structural protein of bone
What does osteocalcin stimulate?
stimulates insulin secretion of pancreas
osteocytes (2)
- former osteoblast that have become trapped in the matrix they have deposited
- contribute to homeostasis (phosphate & calcium ions //bone density)
lacunae
tiny cavities where osteocytes reside
canaliculi
channels that connect lacunae; are reached by cytoplasmic processes
osteoclasts (3)
- bone dissolving cells (mesenchymal) found on the bone surface
- different origin from rest of bone cells
- very large having 3-4 nuclei
Where does osteoclasts develop from?
same bone marrow stem cells that give rise to blood cells
ruffled borders
side facing bone surface that increases surface area of the plasma membrane
resorption bays
howships lacunae
pits on surface of bone where osteoclasts reside
remodeling
results from combined action of osteoclasts and osteoblast (balance of removing & building)
What 2 structural materials are bone made of?
ceramic(hydroxyapatite) & a polymer (collagen)