40.tissues of MS Flashcards
fmost abundant protein in the body
collagen
T/Fproteoglycans are one class of glycoproteins
TRUEGlycoprotein = polypeptides covalently linked by carbohydratesProteoglycan = one class of glycoproteins, they are a polypeptide that is covalently linked to amino sugars (GAGs)
define stress vs strain
stress= force per unit areastrain= deformation produced in a given direction
what is adaptation of a tissue
ability of the tissue to actively maintain specific properties (such as strength and stiffness) that are required for their function and integrity
properties of all musculoskeletal tissue
contain a small amount of progenitor cellsmechanosensitivitymechanotransductioncellular interconnectedness (except NOT in cartilage)
components of ECM
–collagen–proteoglycans (aggrecan)–elastin/elastic fibers–Misc proteins, proteolipids, glycoproteins (fibronectin)
tensile properties of collagen rich connective tissues are determined by what factors
–intrinsic mechanical properties of collagen type–orientation–packing–diameter of collagen fibrilsex. tendon–parallel and dense collagen, therefore withstand unidirectional tensile loads and high stiffness in that directionarticular cartilage–smaller, sparse, weblike collagen, therefore withstands multidirectional tension and resistance to deformation in several directions
major proteoglycan in the body
glycoprotein–>proteoglycan = AGGRECAN (made up on GAGS–keratin and chondroitin sulfate)massive 100 aggrecan per hyaluronic acid backbone, linked to hyaluronic acid via link protein, high level of hydration and turgidity (critical for compressive properties—ex. articular cartilage)
types of classes of glycosaminoglycans
- glycosaminoglycans–keratan sulfate, heparan sulfate2. galactosaminoglycans–chondroitin sulfate
what is hyaluronic acid
nonpeptideconjugated, nonsulfated glycosaminoglycan
what is the most abundant GAG in the body
chondroitin sulfate
name the non sulfated GAG
hyaluronic acid
where is keratin sulfate most prevalent in
bone and cartilage
most negatively charged GAG
heparan sulfate
characteristics of elastin/elastic fibers in connective tissue
flexibleextensibleresilientinsolublerecoilundergo elastogenesis during reparative phase fun fact: make up majority of Nuchal Ligament
deformation or strain of elastic fibers
70% of their resting lengthmax extension: 220% before losing strength
two forms of bone in the adult:
- cortical—compact, osteonal bone 2. cancellous—spongy, trabecular bone
what type of collagen is the periosteal ECM and bone primarily made up of
type I(articular cartilage is type II)
difference btwn woven and lamellar bone
lamellar bone–highly organized, layered bone, alternating orientationwoven bone–loose, disorganized (seen in initial phases of endochondral ossification either during growth or indirect fracture healing)
mineral content of bone
calcium hydroxy apatite
T/Fbone is least strong under tension
TRUEstrongest under compressionweakest under tension
what is wolff’s law
ability of bone to remodel adaptively in response to a mechanical load
which cell is the primary mechanotransducer in bone
osteocyte
most bone remodeling occurs on what surface
trabecular or cortical surfacesHOWEVER, can still occur WITHIN Haversian system of cortical bone (osteoclasts cutting cones, followed by osteoblasts–direct or primary cortical remodeling)
