SKELETAL SYTEM Flashcards
(182 cards)
Considered the most important organ system in the study of vertebrate morphology
significance to morphology of the skeletal system
The __ is a group of organs that originates
from the endodermic cells of the developing embryo. The organs of the skeletal system (osteo-) is primarily
composed of two (2) types of cells
skeletal system
(2) types of cells in the skeletal system
cartilaginous cells (chondrocytes and chondroblasts)
calcified cells (osseous cells –osteocytes, osteoclasts and osteoblasts)
forms an important part of the endoskeleton in ALL VERTEBRATES
cartilage
Comprise the most of the endoskeleton in HIGHER VERTEBRATES
bones
Inorganic components of bone comprises __% of the dry weight (calcium hydroxyapatite
crystal) – gives compressive strength
60%
organic component of bone – gives bone tensile strength
collagen
Provides support and movement
* Protects vital organs
* Major site of red marrow for production of blood cells.
* Plays a role in the metabolism of minerals (calcium and phosphate)
bones
(2) basic structural types of bones
compact bone
spongy bone
type of bone
solid, strong bone that is resisstant to bending located alonf he diaphysis of long bones
provides solid structure to the skeletal frame
forms a hollow tube called the medullary cavity
compact bone
type of bone
made of many branching, bony plates
located in the epiphysis of long bones
spongy bone
type of bone
reduces the weight of the bone
provides strength to bones especially against forces of compression (standing, running)
bone marrow is house between the bony plates
spongy bone
(2) bone formation
endochondral
intramembranous
type of bone formation
highly organizeed transformation of cartilage to bone
occurs at the primary and secondary ossification centers
all tubular and flat bones; vertebrae; base of the skull; the ethmoid; medial and lateral ends of the clavicles
stops after skeletal maturity
contributes to increase in bone length
endochondral bone formation
type of bone formation
appositional periosteal bone formation
cortex of tubula and flat bones; bones of the skll (calvarium); facial bones
increase in bone thicknes
partitcipates in the remodeling process throughout life
intramembranous bone formation
the vertebrate skull conists of (3)
neurocranium/chondrocranium
splanchnocranium
dermatocranium
composition of the vertebrate skull
includes the box that encloses the brain and the capsules surrounding the sense organs
protects the brain
neurocranium/chondrocranium
composition of the vertebrate skull
the visceral portion of the skull that supports the gills and contributes to the jaws
splanchnocranium
composition of the vertebrate skull
the dermal bone that is believed to be derived from the external armor of primitive fish
this bone contributes to the brain case and the jaws
dermatocranium
retin a carilaginous enruocranium (or chondrocranium) throughout life
cartilaginous fishes
retain highly cartilaginous neurocranium that is covered by membrane bone
bony fishes, lungfishes, & most ganoids
embryonic cartilaginous neurcranium is largely replaced by replacement bone (the process of endochondral ossificaition occurs almost simultaneously at several ossification centers)
other bony vertebrates
(4) neurocranial ossification centers
occipital center
sphenoid center
ethmoid center
otic centers
neurocranial ossification center
tend to remain cartilaginous and form:
anterior to sphenoid
cribiform plate of ethmoid & several conchae (or ethmoturbinal bones)
ethmoid centers