CHAPTER 6- BONES AND SKELETAL TISSUE Flashcards
hyaline cartilages
provide support, flexibility, and resilience. most abundant type.
in: cargilage in nose and ribs
elastic cartilages
similar to hyaline cartilages, but contain elastic fibers.
fibrocartilages
collagen fibers- have great tensile strength.
in: between vertebral disks, meniscus, and pubic bones
skeletal cargilage
heals cery sloww
growth of cartilage
- appositional
- interstitial
calcification of cartilage occurs during…
- normal bone growth
- old age
apposition growth of cartilage
chondroblasts secrete matrix against the EXTERNAL force of existing cartilage
interstitial growth of cartilage
chondrocytes divide and secrete new matrix, expanding cartilage from WITHIN
bones of the skeleton
two main groups, by location:
- axial skeleton (ribs, vertebrae, skull- right down axis)
- appendicular skeleton (all limbs + pelvis & os coxa)
classification of bones by shape
- long bones (longer than wide)
- short bones (cube shaped- in wrist and ankle; sesamoid bones (in tendons- like patella)
- flat bones (slightly curved- sternum)
- irregular bones (complicated shapes- vertabrae)
function of bones
support
- for body and soft organs
protection
- for brain, spinal cord, and organs
movement
- levers for muscle action
functions of bones cont…
storage
- minerals (calcium and phosphorous) and growth factors
blood cell formation
- (hematopoiesis) storage in bone cavities
*triglyceride (energy) storage in bone cavities
bone markings: bulges, depressions, and holes serve as…
- sites of attachment for muscles, ligaments, and tendons
- joint surfaces
-conduits for blood vessels and nerves
bone markings: projections
projections that help to form joints:
head
- bony expansion carried on narrow neck
facet
- smooth, nearly flat articular surface
condyle
- rounded articular projection
ramus
- armlike bar
bone markings: depressions and openings
meatus
- canal-like passageway
sinus
- cavity within a bone
fossa
- shallow, basinlike depression
groove
- furrow
fissure
- narrow, slitlike opening
foramen
- round or oval opening through a bone
bone textures
compact bone
- dense outer layer
spongy bone
- honeycomb of trabeculae
structure of a long bone- diaphysis
diaphysis (shaft)
- compact bone collar surrounds medullary (marrow) cavity
- medullary cavity in adults contains fat (yellow marrow)
structure of a lone bone- epiphyses
epiphyses
- expanded ends
- spongy bone interior
- epiphyseal line (or growth plate, if cartilage)
- hyaline cartilage on joint surfaces
membranes of bone- periosteum
periosteum:
1. outer fibrous layer
2. inner osteogenic layer
- osteoblasts (bone-forming cells)
- osteoclasts (bone-destroying cells)
- osteogenic cells (stem cells)
- nerve fibers, blood vessels, and lymphatic vessels enter the bone via nutrient foramina
- periosteum secured to underlying bone by perforating fibers
membranes of bone- endosteum
endeosteum:
- delicate membrane on internal surfaces of bone
- also contains osteoblasts and osteoclasts
structure of short, irregular, and flat bones
- periosteum- covered compact bone on the outside
- endosteum-covered spongy bone within
- spongy bone called diploe in flat bones
- bone marrow between trabeculae
location of hematopoietic tissue (red marrow)
red marrow cavities of adults:
- trabecular cavities of the heads of the femur and humerus
- trabecular cavities of the diploe of flat bones
red marrow of newborn infants:
- medullary cavities and all spaces in spongy bone
microscopic anatomy of bone
cells of bones:
osteogenic cells
- stem cells in periosteum and
endosteum that give rise to osteoblasts
osteoblasts
- bone-forming cells
osteocytes
- mature bone cells
osteoclasts
- cells that break down (resorb) bone
matrix
- involved in bone repair
microscopic anatomy of bone: compact bone
perforating canals
- perpendicular to central canal
- connects blood vessels and nerves of periosteum and central canal
lacunae- small cavities that contain osteocytes
canaliculi- hairlike canals that connect lacunae to each other and the central canal
