I. Osteology: Cells, matrix, ossification, bone density, bone variation Flashcards
What are the four basic tissues of the human body?
epithelial, muscle, neural and connective
What is osteology?
the study of bone
What are the three primary cell types of bones?
osteoblasts, osteocytes, and osteoclasts
What is the fuction of each type of bone cell?
Osteoblast-form bone
Osteocyte- maintain and nurture bone
Osteoclast0 remodel bone
What are the bone cells embedded in?
an amorphous matrix consisting of groudn substance, protein fibers and various minerals
What is the primary constituent of the ground substance?
glycosaminoglycans
What types of glycosaminoglycans predominate in bone?
chondroitin sulfate, keratin sulfate and hyularonic acid
What is the principal type of protein fiber in bone?
Collagen type 1
What are the primary constituents of the bone mineral?
calcium, phosphate, citrate and carbonate ions
What is the most frequently described deposit in bone?
hydroxyapatite
Bone is also the repository for what additional ions?
sodium, magnesium, flouride, 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 3 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 tissue?
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?
the skull
Which of the skull bones are derived from intramembranous ossification?
the nasal, palatine, vomer, lacrimal, zygomatic, maxilla, frontal, parietal, most of the mandible, the squama 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 ossifcation
What is the timing for the appearance of ossification in cartilage?
from the second to fifth month in utero
What part of the skill is derived from endochondral ossification?
chondrocranium
What bones are formed from the chondrocranium?
the 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?
the mandible, sphenoid, temporal and occipital bones
Which bone of the appendicularskeletion is formed bu both endochondral and intramembranous ossification?
the clavicle
What are the primary names fiven to the centers of ossification based on time of appearance?
Primary centers of ossification appears before birth
secondary centers of ossification appears after birth
Mature bones 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?
the periosteum
What is the name given to the fibro-cellular lining of the bone?
the endostrum
***What are the primary sources of variation observed in bone?
Sexual dimorphism (gender variation), ontogenetic variation (growth or age variation), geographic or population based variation (ethnic variation) and idiosyncratic variation (individual variation)
Differenced in the number of morphology of vertebrae within the population based on male and femal variation is identified as which type of variation?
Sexual dimorphism or gender variation
Differences in the number or morphology of vertebrae withing the population based on age or development variation is identified as whi9ch type of variation?
ontogenetic variation
