Vertebrate Zoology Exam 2: Mineralized Tissues and Ossification

*metaphysis - zone adjacent to e? (g?) plate on d? side

*metaphysis - zone adjacent to epiphyseal (growth) plate on diaphyseal side

A. Calcification (cartilage becomes calcified) Background on cartilage F? (derived from p? cells): produce c? where? C?: forms s? G? and p? in matrix what cells? eventually become e? in matrix and then they are called what? L?; cells retain vitality; how many cells typically in one lacuna? L?): (L) - b/l/c What cells have reduced m? ability What action? supplies lacunar cells; poor what? supply

A. Calcification (cartilage becomes calcified) Background on cartilage Fibroblast (derived from pluripotent cells): produce collagen in matrix Chondroblasts (chondro means cartilage): forms sulfated GAGs and proteoglycans (proteins with GAG side chains) in matrix Chondroblasts eventually become entombed in matrix, once they are entombed are called chondrocytes. space is called a lacuna Lacunae; cells retain vitality; 2-4 cells within a lacuna. lacuna means basin, lake or cavity. lacun(a) (L) - basin/lake/cavity Chondrocytes w/ reduced mitotic ability Diffusion supplies lacunar cells; poor vascular supply

A. O? in p? of cartilage model produce m? bone (first step in what ossification?) what produces membrane bone? what 2 terms? refer to what kind of CT?

A. Osteoblasts in perichondrium of cartilage model produce membrane bone (first step in endochondral ossification). perichondrium produces membrane bone. perichondrium vs periosteum refer to dense irregular CT around bone, and once its around bone its called periosteum.

Major Events (6 points)

A. Osteoblasts in perichondrium of cartilage model produce membrane bone B. Calcification C. Vascular invasion of diaphysis region D. Vascular invasion of epiphysis (parallel process as before) ...followed by ossification in epiphyses E. Appositional growth F/G. Epiphyseal plate closure

what kind of? bone in many diff teleost lineages (is this reversal or convergence?)

Acellular bone in many diff teleost lineages (convergence in several of the lineages)

be able to identify these structures on the image on slide #19

Ameloblasts Enamel Dentin Odontoblasts Dental pulp

Ameloblasts - e?; crown; dental whats?

Ameloblasts - enamel; crown; dental caries cavities are caries since caries means rotten. once enamel is gone, cavities can happen

B. C? C? in d? h?; release what? salts into where? C? become what? in where?

B. Calcification Chondrocytes in diaphysis hypertrophy (means cells get larger); release Ca salts into matrix. Chondrocytes become entombment in calcified cartilage

B. Dentin Formation Mineralization & what action?; cell what? is retained Forms only where?; usually near which? border O? cluster superficial to/near dermal whats? O? processes (aka cell whats?) of whats? deposit what material? - 30% organic or inorganic? (name the 2 materials) - 70% organic or inorganic? (name the 1 materials? (aka what is it?)) Cell extensions project towards or away? from blood vessel. what are they pointing towards or away from? O? "r?" ; which? processes become embedded where?

B. Dentin Formation Mineralization & entombment; cell vitality retained Forms only in dermis; usu near epidermal border Odontoblasts cluster superficial to/near dermal blood vessels Odontoblastic processes (aka cell extensions) of odontoblasts deposit dentin - 30% organic (collagen & GAGs (glycosaminoglycans)) - 70% inorganic (hydroxyapatite (aka calcium phosphate) Cell extensions project away from blood vessel towards epidermis Odontoblast "retreat" ; odontoblastic processes become embedded in dentin

Bone Formation m? bone (is there a cartilage precursor?...) vs e? bone Orientation of which type of CT? in endochondral bone a. L? bone: "what?" ; regular arrangement of what CT type and what else? -concentric layers in c? bone (think o?)

Bone Formation membrane bone (no cartilage precursor...) (an example of membrane bone is dermal bone) vs endochondral bone Orientation of collagen a. Lamellar bone: "layered" ; regular arrangement of collagen & bone (collagen is orientated so that it provides layers around osteonic system. outside of osteonic canal have lamellae. -concentric layers/lamellae in compact bone (think osteons)

Bone has similar composition as dentin - #% organic (c? & G?) -#% inorganic (h?)

Bone has similar composition as dentin - 30% organic (collagen & GAGs (glucosaminoglycan)) 70% inorganic (hydroxyapatite (crystalline calcium phosphate))

Bone: osteoblastic extensions surrounded by hardened matrix = what/singular form of the word? Dentin: odontoblastic extensions surrounded by hardened matrix = ?

Bone: osteoblastic extensions surrounded by hardened matrix = canaliculi/canaliculus Dentin: odontoblastic extensions surrounded by hardened matrix = canaliculi or dental/dentin tubules

Bone: similar to dentin, but several differences... cells that form bone are called whats? o? usually are how in position? cytoplasmic extensions (aka what? extensions) project in which? direction what? extensions contact those of other whats? (does cell death occur?) usually no cell what action? w/ h? production (by whats?)

Bone: similar to dentin, but several differences... cells (osteoblasts) osteoblasts usu perivascular (encircling or surrounding blood vessel) in position cytoplasmic extensions (osteoblastic extensions) project in several directions osteoblastic extensions contact those of other osteoblasts (typically no cell death) usu no cell retreat w/ hydroxyapatite production (by extensions)

C. V? invasion of d? region what things? invade/grow into the what? model & initial which? cavity forms; mechanism? (what is this process called?) C? layer cells (which? cells in p?) differentiate & enter d? w/ whats? O? & o?-lineage cells arrive in blood via invading what? which #? degree center of ossification Meanwhile ...which process continues where?

C. Vascular invasion of diaphysis region BV invade/grow into the cartilage model & initial medullary cavity forms; mechanism? (vascular invasion) Cambium layer cells (opr cells in periosteum) differentiate & enter diaphysis w/ BV Osteoclast & osteoblast-lineage cells arrive in blood via invading BV 1o center of ossification (because this is where bone forms first) Meanwhile ...chondrogenesis (generates cartilage) continues in epiphysis

Calcified cartilage; what material? salts form in matrix; usually what 2 types of cartilage? calcium salt deposition further entombs which cells? which cells die?; usually normal Examples: j? & v? of which group of animals? what type of? bone formation; cartilage "m?" calcifies in initial stages atypical cartilage what? - joint damage in o? patients (calcium p? d? & calcium what?)

Calcified cartilage; Ca salts form in matrix; usu hyaline or fibrocartilage calcium salt deposition further entombs chondrocytes lacunar cell death; usually normal Examples: jaws & vertebrae of chondrichthyes endochondral bone formation; cartilage "model" calcifies in initial stages atypical cartilage calcification - joint damage in osteoarthritis patients (calcium pyrophosphate dihydrate & calcium phosphate)

C? Bone (aka s/t? bone) P/l-like?; t? beams/bars (architectural trusses) T?: l? arranged as r/p? with or without? organized o? systems Nutrients obtained from vessels in what? in adjacent what? spaces

Cancellous Bone (aka spongy/trabecular bone) Porous/lattice-like; trabeculae beams/bars (architectural trusses) Trabeculae: lamellae arranged as rods/plates w/o organized osteonic systems Nutrients obtained from vessels in (red) marrow in adjacent trabecular spaces

Classifications/Descriptors of Bone Presence/absence of whats? what kind of? bone vs what kind of? bone (common in which animals?) Appearance 1. C? bone (aka o/H bone) 2. C? bone (cancell = what-work?) ; aka what? bone or t? bone C? bone: t? (trab = what/what?) & what? spaces (what are these spaces filled with?)

Classifications/Descriptors of Bone Presence/absence of cells cellular bone vs acellular bone (common in fishes) (acellular means cells die at functional maturity or they retreat from mineralized tissue) Appearance 1. Compact bone (aka osteonic/Haversian bone) 2. Cancellous bone (cancell = latticework) ; aka spongy bone or trabecular bone Cancellous bone: trabeculae (trab = beam/bar) & trabecular spaces (filled with bone marrow)

Common themes regarding mineralized tissue: a. is cartilage or collagen present? C? bundles form a what? for mineral what? in where? b. H? is abundant in what 3 materials? dont need to know the molecular formula, just know that is refers to the crystalline nature of the salt more than the ingredients.

Common themes re mineralized tissue: a. Collagen is present Collagen bundles form network for mineral deposition in CT b. Hydroxyapatite is abundant in dentin, bone & enamel Ca10(PO4)6(OH)2

Compact Bone Mineralized what kind of CT? surrounding o? canal (avoid which 2 terms in my usage)? Each canal: contains what 3 things? v, lv, n Layers of bone surrounding c? = c? l? L? positioned between whats? Numerous c? emanating from where? O? canal & surrounding l? w/ l? = o? (older usage -- H? system)

Compact Bone Mineralized collagen surrounding osteonic canal (avoid central canal & Haversian canal usage) Each canal: vascular supply (arteriole, venule), lymph vessel, neurons Layers of bone surrounding canal = concentric lamellae (means layered) Lacunae positioned between lamellae Numerous canaliculi emanating from lacunae. Osteonic canal & surrounding lamellae w/ lacunae = osteon (osteonic system) (older usage -- Haversian system)

Compared to bone, cartilage is ... vascular or avascular?; lower or higher? metabolic rate has diff what & what? components (so diff what? properties) what type of cells? suspended in what?-rigid matrix matrix with f? (e? shaped) proteins (e?, c/r?) matrix also rich in whats?

Compared to bone, cartilage ... is avascular; lower metabolic rate has diff cellular & matrix components (so diff structural properties) chondrocytes suspended in semi-rigid matrix matrix with fibrous (elongate shape) proteins (elastin, collagen/reticulin) matrix also rich in polysaccharides

D. Vascular invasion of e? (parallel process as before) ... followed by o? in where? what # degree center of what action?

D. Vascular invasion of epiphysis (parallel process as before) ... followed by ossification in epiphyses 2o center of ossification

Dentin pulp - unmineralized or mineralized? soft tissue what does dentin/dental pulp contain? o? c & g? f? m? (derived from which cells?) v & nt?

Dentin pulp - unmineralized soft tissue odontoblasts collagen & glycoprotein fibroblasts macrophages (derived from monocytes) macro means big and phage means eater, big eater is a macrophage vascular & neural tissue

which ossification is faster? what process continues in what region? why is this important?

Diaphyseal ossification more rapid than epiphyseal ossification Chondrogenesis continues in epiphyseal plate region - Impt because ...? as long as chondrogenisis at the cartilaginous plate exceeds ossification, this keeps bone growing longer.

Diaphysis (diaphyses): refers to what part of a bone? Epiphysis: what part(s) of the bone? Metaphysis: between what 2 parts of a bone? Epiphyseal plate (general term?) Medullary cavity, is what part of bone and what 2 types of bone? is it vascularized, what marrow type? -phy = ? -sis = ? dia = ?/? meta- ? epi = ?/?

Diaphysis (diaphyses): refers to central portion or shaft of a bone. Epiphysis: the ends of the bone. Metaphysis: between epiphysis and diaphysis (is transitional area). Epiphyseal plate (aka growth plate) Medullary cavity: centrla area of cross section is trabecular or cancellous bone, is highly vascularized and has yellow marrow in it. -phy = growing -sis = act of dia = separate/apart meta- =boundary epi = upon/on

E. Appositional growth = Continued o? on bone what? (via which? cells in where of what?) this is membrane bone formation again...this helps bone grow how?

E. Appositional growth = Continued ossification on bone surface (via osteoprogenator cells in cambium of periosteum) this is membrane bone formation again...this helps bone grow in width/diameter (keeps bone from getting long and skinny).

what kind of? cartilage in where?, p?

Elastic cartilage in epiglottis, pinna

Enamel: ~#%? inorganic or organic? h? (aka what?); does it contain cells? formed by what cells? (what kind of? origin) form e? & association whats? (e? & a?)

Enamel: ~96% inorganic hydroxyapatite (aka calcium phosphate, calcium hydroxide crystal); acellular Ameloblasts (epidermal origin) form enamel & assoc proteins (enamelin & amelogenin)

F/G. E? plate what action? this means what occured?

F/G. Epiphyseal plate closure rate of bone formation exceeded that of cartilage formation. have plate closure when this occurs.

what kind of cartilage? in which? discs & s? of which? girdle

Fibrocartilage in intervertebral discs & symphyses of pelvic girdle (is within pubic symphysis)

Comparative Histology Comments Haversian bone in limited to what group of animals? (is this cellular or acellular bone?, where do the cells reside?) Some what fishes? w/ cellular or acellular? bone *no o? w/in mineralized matrix *no c?; no l? "d? bone" sensu stricto periosteal opr activity & osteoclast invasion possible Poor what? if low Ca in diet and water

Haversian bone in gnathostomes (cellular bone, cells reside within hydroxyapatite matrix) Some teleosts w/ acellular bone *no osteocytes w/in mineralized matrix *no canaliculi; no lacunae "dead bone" sensu stricto periosteal opr activity & osteoclast invasion possible Poor repair if low Ca in diet and water

Herps (turtles and salamanders) w/ l?, cellular or acellular? bone which term for bone used mostly in mammals?

Herps w/ lamellar, cellular bone Osteonic bone mostly in mammals

H? cartilage least or most? differentiated; what color is it? t?; often converted to what? Examples: "what? plate" in what kind of? bones t? rings a s? of joints L?

Hyaline cartilage least differentiated; translucent; often converted to bone Examples: "growth plate" in limb bones tracheal rings articular surfaces of joints larynx

(LAGs??) common in which animals?; some whats? A? (not l? in o? systems) often used as what kind of? technique Tree ring analogy in bone xs visible at high mag ("what?") LAGs from a) *E? stress (hot or cold?) b) N? state (food ?/?) what animals is this used on? region? what-therms?

Lines of arrested growth (LAGs) common in herps; some fishes Annulations (not lamellae in osteonic systems) often used as ageing technique Tree ring analogy in bone xs visible at high mag ("layers") LAGs from a) *Environmental stress (cold) b) Nutritional state (food abundance/quality) Temperate ectotherms

which? cavity enlarges as bone grows; how? occurs as consequence of what?

Medullary cavity enlarges as bone grows; how? occurs as consequence of osteoclast activity.

Mineralization = deposition of minerals (what 2 salts?) in CT m? Advantages: - M? for s/s? - M? s? Mineralized tissue: matrix cells may become isolated from blood... = what is the termed used for this? e? can have repercussions on O2/CO2/nutrients/wastes does this result in cell death?

Mineralization = deposition of minerals (Ca and P salts) in CT matrix Advantages: - Mechanical strength/support - Mineral storage Mineralized tissue: matrix cells may become isolated from blood... = entombment O2/CO2/nutrients/wastes may/may not result in cell death

Mineralization involves CT - a CT story Background on CT CT is made up of what 2 things? (c, e) Matrix: can be what 3 consistencies?; usually made of what molecules? - if the CT is f?: what kind of medium is it? - if the CT is s?: what 2 things (s,b) does it do to cells?

Mineralization involves CT - a CT story Background on CT Cells + extracellular matrix Matrix: can be gel-like; hard; fluid; usu protein - if fluid: exchange medium - if structural: supports & binds cells

Mineralization types A. C?, calcified what material? B. D? formation & e? (e and g?) formation C. O? generally dermal or endochrondral? bone? (what to what?) Entombment? Cell death?

Mineralization types A. Calcification, calcified cartilage B. Dentin formation & enameloid (enamel, ganoin) formation C. Ossification, means endochrondal bone (cartialge to bone). Entombment? Cell death? different answers to these questions ahead

give 4 examples for mineralization. b, c, d, e (e)?

Mineralized examples: bone, cartilage, dentin, enamel (or enameloid means enamel like)

Dentin formation continued Odontoblastic processes in dentin matrix appear as (microscopic) "whats"? = c? or d? t? Odontoblasts aggregate near whats?, form dental what? Dentin later covered by epidermal what? (aka what 2 other names?) E? produced by a? where? E? applied to (u/s?) surface of what? give two examples where dentin is found

Odontoblastic processes in dentin matrix appear as (microscopic) "tunnels" = canaliculi (singular is canalicus) or dentin tubules Odontoblasts aggregate near bv, form dental pulp Dentin later covered by epidermal enameloid (enamel, ganoin) Enameloid produced by ameloblasts in epidermis Enameloid applied to (upper/superficial) surface of dentin teeth; fish scales

Osteoblastic extensions persist as microscopic "whats?" through mineralized what? tissue = c? Parallel morphology as which? processes in dentin Osteoblasts ultimately reside within where? (w/ what kind of? fluid) Osteo-what? (what kind of cell is it?): osteoblast (what kind of cell is it?) w/in a what? surrounded by bony what? How many? cells per lacuna? Cells retain direct/indirect access to what? supply via c?

Osteoblastic extensions persist as microscopic "tunnels" through mineralized bone tissue = canaliculi Parallel morphology as odontoblastic processes in dentin Osteoblasts ultimately reside in lacunae (w/ interstitial fluid) Osteocyte (bone cell): osteoblast (bone forming cell) w/in lacuna surrounded by bony matrix One cell/lacuna Cells retain direct/indirect access to vascular supply via canaliculi

Other examples of heterotopic bone: - o c? (fibrous CT between what 2 things in the heart?; inter-what? s?) in which 2 animals? r?: examples of these animals?

Other examples of heterotopic bone: - os cordis (fibrous CT between Atrium & Ventricle; interventricular septum) in ruminants & otters ruminants: (animals with cloven hooves) deer, cattle, goats, sheep, caribou, moose, giraffes (os means bone cordis means heart)

P? canals (formerly V?'s canals or t? canals) allow communication between whats? Blood vessels within what? ultimately communicate w/ vessels outside of the bone what are the openings on the bone surface called? "n f?" so what canals communicate to exterior and what are the openings called?

Perforating canals (formerly Volkmann's canals or transverse canals) allow communication bet osteons Blood vessels in osteon ultimately communicate w/ vessels outside of the bone "nutrient foramen" perforating canals communicate to exterior and opening is called nutrient foramen

Perichondrium: (how many layers?) Outer layer = f? layer w/ which cells? Inner layer = c? layer w/ o? (aka?) cells (what do these cells become? which? cells in which? layer of which? region differentiate; o? ... which ... produce a "bone c?/s?" on the c? model surface (thus m? bone...)

Perichondrium: (has 2 layers) Outer layer = fibrous layer w/ fibroblasts Inner layer = cambium layer w/ osteoprogenitor (opr) cells (they become osteoblasts). opr cells in cambium layer of diaphysis region differentiate; osteoblasts ... which ... produce a "bone collar/sheath" on the cartilage model surface (thus membrane bone...)

Plate closure in all tetrapods? Fate of epiphyseal plate does what? across taxa Determinant vs indeterminant growth - What groups?

Plate closure in all tetrapods? Fate of epiphyseal plate varies across taxa Determinant (individual do not grow throughout their whole lives) vs indeterminant (growth occurs throughout the organisms whole life, though it may slow down substantially the older the animals gets) - What groups? mammals and birds have determinant growth, turtles and lizards have indeterminant growth.

Red marrow in spaces between t? H? tissue; what-esis? (aka h?) *Compare yellow marrow (in m? cavity) Red marrow very abundant in what kind of? bones (roofing bones of s?, r?, s?)

Red marrow in spaces between trabeculae (lamellae) Hemopoietic tissue; hemopoiesis (aka hematopoiesis) *Compare yellow marrow (in medullary cavity), yellow marrow is fat deposition site. Red marrow very abundant in flat bones (roofing bones of skull, ribs, scapulae (aka shoulder blade)

Several types of Membrane Bone a. Dermal bone (examples from lab?) b. Perichondral/periosteal bone (covers what?) c. Heterotopic bones (usu response to what kind of stress?) - an example are what bones? ex: p? in which? tendon, p? bone in tendon of f c u?

Several types of Membrane Bone a. Dermal bone (turtle shells, roofing bones of skull, bone of pectoral girdle) b. Perichondral/periosteal bone. covering of bone, covering of cartilage prcursor is perichondral bone. c. Heterotopic bones (usu response to mechanical stress) - sesamoid bones ... any bone that forms in a tendon. ex: patella in quadriceps tendon, pisiform bone in tendon of flexor carpi ulnaris

Types of Bone Cells (cell activity) O? cells: specialized or unspecialized?; what-dermal? what-chyme? origin; mitotic or not mitotic? "committed" to bone lineage; do they form bone? (so are or are not what?) what-blasts?: what-genesis?; mitotic or not mitotic? Osteo-whats?: what cell within where?; involved in what action?; mitotic or not mitotic? Osteo-whats?: one or multiple nuclei?; derived from fusion of which? p? within bone what? (what do they do to bone?) formed from the same lineage of which? cells forms m? (blood) & tissue m?.

Types of Bone Cells (cell activity) Osteoprogenitor cells: unspecialized; mesodermal mesenchyme origin; mitotic "committed" to bone lineage; not osteogenic Osteoblasts: osteogenesis; not mitotic Osteocytes: osteoblast in lacuna; maintenance; not mitotic Osteoclasts: multinucleate; derived from fusion of hematopoietic progenitors in bone marrow (destroy bone, can breakdown calcified tissue) Osteoclasts are formed from the same lineage of hematopoietic cells forms monocytes (blood) & tissue macrophages.

Types of Bone Formation I. M? bone Is there a cartilage precursor? what-dermal? what-chyme? cells become arranged in what?-like "m?" = Membranous b? B? refers to - aggregation of differentiated or undifferentiated? p? cells Cells of b? ultimately become o? & form what?

Types of Bone Formation I. Membrane bone No cartilage precursor Mesodermal mesenchyme cells become arranged in sheet-like "membranes" = Membranous blastema (each layer of cells is referred to as membranous blastema). Blastema refers to - aggregation of undifferentiated pluripotent cells Cells of blastema ultimately become osteoblasts & form bone

what houses a osteocyte? what houses osteoblastic extensions?

a lacuna houses a osteocyte a canaliculus houses an osteoblastic extension

all bone/bone cells are derived from what?

all bone/bone cells are derived from mesodermal mesenchyme

another example of heterotopic bone is the what?

another example is rostral bone (nose bone like in wild hogs).

b. Non-L? (w?) bone: c? fibers arranged randomly in what-lacing? networks Ex: bone repairing after fracture; rapidly growing bones in fetus

b. Non-lamellar (woven) bone: collagen fibers arranged randomly in interlacing networks Ex: bone repairing after fracture; rapidly growing bones in fetus, some fishes have permanently non-lamellar bone initially when bone is repaired it will appear as non-lamellar bone, quickly growing, then its converted to lamellar bone.

another example of heterotopic bone is? in fibrous CT above u? in unrelated mammals bats, rodents, dogs, gorillas, chimps, otter, walrus, raccoon

baculum in fibrous CT above urethra in unrelated mammals bats, rodents, dogs, gorillas, chimps, otter, walrus, raccoon

begin quiz 4 material C. Ossification Not restricted to what layer? (compare dentin) collagen or cartilage? is abundant spaces between c? fibers become filled w/ what material? bone cells reside within whats?

begin quiz 4 material C. Ossification Not restricted to dermis (compare dentin which is always restricted to the dermis) collagen abundant spaces between collagen fibers become filled w/ hydroxyapatite bone cells reside in lacunae

blast means?

blast means some cell is generating something

osteoblasts form what?

bone

chondroblasts form what?

cartilage

where does chondrogenesis occur?

chondrogenesis occurs in the epiphyseal (growth) plate.

fibroblasts form what 2 things?

collagen fibers elastic fibers

second type of mineralization is what formation?

dentin formation is second type of mineralization.

what are the 3 types of membrane bone?

dermal bone perichondral/periosteal bone heterotopic bone

ameloblast form what 2 things?

enamel and enameloid

when is epidermal enameloid called ganoin?

enameloid is called ganoin when its associated with scales of some fishes

Endochondral bone is next

endochondral bone comes from a cartilage precursor

first type of mineralization is what?

first type of mineralization is calcification

if what is taken over by what? what occurs?

if chondrogenesis is taken over by bone formation the bone stops growing longer

where does dentin form?

in the dermis

mesenchyme. The part of the embryonic mesoderm that consists of loosely packed, unspecialized cells that are set in a gelatinous ground substance, from which connective tissue, bone, cartilage, and the circulatory and lymphatic systems develop.

mesenchyme mes·en·chyme (měz'ən-kīm', měs'-) n. The part of the embryonic mesoderm that consists of loosely packed, unspecialized cells that are set in a gelatinous ground substance, from which connective tissue, bone, cartilage, and the circulatory and lymphatic systems develop.

myoblasts for what?

muscle

odontoblasts have what kind of origin and form what?

neural crest origin form dentin

be able to identify parts on the figure slide #27

nucleus, cell process/extension, lacuna, calcified matrix, decalcified matrix

which type of cells produce dentin?

odontoblasts

what is the third type of mineralization end quiz material

ossification end quiz material

so what do osteoclasts do?

osteoclasts get through bone into where calcified cartilage is and destroy it and then form bone. osteoclasts get into diaphysis and erode to vascularize diaphysis.

be able to identify osteon osteonic canal perforating canal Perforating canal (Volkmann's canal); nutrient foramen

osteon osteonic canal perforating canal Perforating canal (Volkmann's canal); nutrient foramen

slide #6 draw flow diagram what is the precursor?

pluripotent mesenchymal precursor pluripotent lineages, wandering cells potent means power

red marrow is what kind of tissue and is involved in what formation?

red marrow is hemopoietic tissue (hemopoiesis), it is involved in the formation of blood cells

sesamoid bones are what kind of bones?

sesamoid bones are heterotopic bones and heterotopic bones are membrane bones

structural = r? CT: what popular molecule? w/ what 3 things? a. g? (aka whats?) (usually c? s? b. p? (core protein w/ attached what kind of? chains) c. what kind of protein?: c?, e? f?, r? (= what kind of linked? c?; forms mesh or r?; common support in what kind of? tissue)

structural = rigid CT: H2O w/ a. glycosaminoglycans (usu chondroitin sulfate); "GAGs" [glycans means polysaccharides, GAG is some sort of carbohydrate with protein, so carbohydrates with amino acid side chains] b. proteoglycans (core protein w/ attached GAG chains) c. fibrous protein: collagen, elastic fibers, reticular (= cross-linked collagen; forms mesh or reticulin; common support in soft tissue)