Cells, Matrix, Ossification, Bone Density, Bone Variation Flashcards
What are the four basic tissues of the human body?
epithelial, muscle, neural, and connective tissue
What is osteology?
study of bones
What is the function of each type of bone cell?
osteoblast - form bone
osteocyte - maintain or nurture bone
osteoclast - remodel bone
What are the bone cells embedded in?
an amorphous matrix consisting of ground substance, protein fibers and various minerals
What is the primary constituent of the ground substance?
glycosaminoglycans
What are the three primary cell types of bones?
osteoblasts, osteocytes, and osteoclasts
What types of glycosaminoglycans predominate in bone?
chondroitin sulfates, keratin sulfates, and hyaluronic acid
What is the principal type of protein fiber in the bone?
collagen type I
What is the primary constituents of the bone mineral?
calcium, phosphate, citrate, and carbonate ions
What is the most frequently described deposit in the bone?
hydroxyapatite
Bone is also the repository for what additional ions?
sodium, magnesium, fluoride, lead, strontium, and radium
What is Wolff’s Law as it pertains to bone?
living tissue will respond to stressors; bone is formed or absorbed in response to various stressors
What three responses of “living” bone were stressed in class?
it has the ability to heal, to remodel under stressors, and to age
Bone is the embryological derivative of which specific connective tissues?
mesenchyme and/or cartilage
What is the name given to the pattern of ossification in mesenchyme?
intramembranous ossification
What is the timing for the appearance of intramembranous ossification?
from the second to third month in utero
What part of the axial skeleton is primarily formed by intramembranous ossification?
skull
Which of the skull bones are derived from intramembranous ossification?
nasal, palatine, vomer, lacrimal, zygomatic, maxilla, frontal, parietal, most of the mandible, the squams of the temporal and occipital bones, and the greater wing of the sphenoid
Which bone of the appendicular skeleton is partially formed by intramembranous ossification?
clavicle
What is the name given to the pattern of ossification in cartilage?
endochondral ossification
what is the timing for the appearance of ossification in cartilage?
second to fifth month in utero
What part of the skull is derived from endochondral ossification
chondrocranium
What bones are formed from the chondrocranium?
inferior nasal concha, ethmoid, and the remainder of the mandible, sphenoid, temporal, and occipital bones
Which skull bones are ossified by both endochondral and intramembranous ossification?
mandible, sphenoid, temporal, and occipital bones
Which bone of the appendicular skeleton is formed by both endochondral and intramembranous ossification?
clavicle
What are the names given to the centers of ossification based on time of appearance?
primary centers of ossification appear before birth
secondary centers of ossification appear after birth
Mature bone is described as being composed of what areas based on bone density?
cortical or compact bone, and spongy, cancellous or trabecular bone
What is the name given to the bone below an articulating surface?
subchondral bone
What is the name of the outer fibro-cellular covering of bone?
periosteum
What is the name given to the fibro-cellular lining of bone?
endosteum
What are primary sources of variation observed in bone?
sexual dimorphism, ontogenetic variation, geographic or population-based variation, and idiosyncratic variation
Differences in the number or morphology of vertebrae withing the population based on male and female variation is identified as which type of variation?
sexual dimorphism or gender variation
Differences in the number or morphology of vertebrae within the population based on age or developmental variation is identified as which type of variation?
ontogentic variation
Differences in the number or morphology based on ethnicity or locational variation is identified as which type of variation?
geographic variation or population based variation
Differences in the number or morphology of vertebrae within the population based on the uniqueness between individuals is identified as which type of variation?
idiosyncratic variation
