Chapter 8: Bone Flashcards

1
Q

Provides solid support for the body, thoracic cavities, and encloses internal cavities containing bone marrow where blood cells are formed

A

Bone tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Serves as a reservoir of calcium, phosphate, and other ions that can be released or stored in a controlled fashion to maintain constant concentrations in body fluids

A

Bone(osseous) tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Found in lacunae between lamellae, with cytoplasmic processes in small canaliculi that extend into the matrix

A

Osteocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Growing cells which synthesize and secrete the organic components of the matrix

A

Osteoblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Giant, multinucleated cells involved in removing calcified bone matrix and remodeling bone tissue

A

Osteoclasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

B/c metabolites can’t diffuse thought calcified matrix of bone, the exchanges btw osteocytes and blood capillaries depend on communication through the very thin, cylindrical spaces of the ___________

A

Canaliculi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The internal surface surrounding the marrow cavity; connective tissue containing osteogenic cells

A

Endosteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

External surface lining of bones; connective tissue containing osteogenic cells

A

Periosteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Produce the organic components of bone matrix including type I collagen fibers, proteoglycans, and matricellular glycoproteins, such as osteonectin

A

Osteoblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Active osteoblasts are located exclusively at the ________ of bone matrix, to which they are bound by ______, typically forming a single layer of _______ cells joined by ______ and ____ junctions

A

Surfaces; integrins; cubodial; adherent; gap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Unique collagen-rich material, between the osteoblasts layer and the preexisting bone surface

A

Osteoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Prominent among the noncollagen proteins secreted by osteoblasts is the vitamin K-dependent polypeptide _________, which together with various glycoproteins binds _____ ions and concentrates this mineral locally

A

Osteocalcin; Ca2+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Long dendritic processes, surrounded by calcifying matrix - radiating from each lacuna

A

Canaliculi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Osteoblasts also release membrane-enclosed _____ ______ rich in alkaline phosphatase and other enzymes whose activity raises the local concentration of phosphate ions

A

Matrix vesicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Matrix vesicles serve as a foci for the formation of ________ crystals, the 1st visible step in calcification

A

Hydroxyapatite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Osteoblasts surrounded by the material secrete and then differentiate as _______

A

Osteocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Osteocytes communicate with one another, nearby osteoblasts, and bone lining cells through ____ ______

A

Gap junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Most abundant cells in bone

A

Osteocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Very large, motile cells with multiple nuclei that are essential for matrix resorption during bone growth and remodeling

A

Osteoclasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Osteoclasts’ origin from the fusion of bone marrow-derived _______

A

Monocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Osteoclast development requires two polypeptides produced by osteoblasts: ________ and the __________

A

M-CSF (macrophage-colony-stimulating factor) and RANKL(receptor activator of nuclear factor-kB ligand)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

In areas of bone undergoing resorption, osteoclasts on the bone surface lie within enzymatically etched depressions or cavities in the matrix known as _____ ______

A

Howship lacunae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

In active osteoclasts, the membrane domain that contacts the bone forms a circular ____ ____ that binds the cell tightly to the bone matrix and surrounds an area with many surface projections, called the ____ _____

A

Sealing zone; ruffled border

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Around the ruffled boarder is a ring of _____, adhering the cell to the bone “microenvironment”

A

Actin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Osteoclast pumps ____ to acidify and promote dissolution of the adjacent hydroxyapatite

A

Protons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Breakdown organic components

A

Collagenases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Most abundant inorganic material in the bone matrix

A

Calcium-hydroxyapatite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

The organic matter embedded in the calcified matrix is 90% ___ _ collagen, but also includes mostly small proteoglycans and multiadhesive glycoproteins such as _______

A

Type I; osteonectin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

External surfaces of all bones are covered by connective tissue of the ______

A

Periosteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Internal surfaces of all bones are covered by connective tissue of the ______

A

Endosteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

An outer fibrous layer of dense connective tissue, containing mostly bundled type I collagen, fibroblasts, and blood vessels

A

Periosteum

32
Q

Bundles of periosteal collagen, that penetrate the bone matrix and bind the periosteum to the bone

A

Sharpey fibers

33
Q

Mesenchymal stem cells located in the periosteum’s inner layer

A

Osteoprogenitor cells

34
Q

Play prominent role in bone growth and repair; produce new osteoblasts

A

Osteoprogenitor cells

35
Q

Densely packed osteons or parallel lamellae; thick, outer region (beneath periosteum) of bones

A

Compact (cortical) bone

36
Q

Interconnected thin spicules or trabeculae covered endosteum; inner region of bones, adjacent to marrow cavities

A

Cancellous (trabecular or spongy) bone

37
Q

In long bones, the bulbous ends called ________ are composed of _____ bone covered by a thin layer of _____ bone

A

Epiphyses; cancellous; compact

38
Q

Bone organization with matrix existing as discrete sheets

A

Lamellar bone

39
Q

Bone organization, newly formed with randomly arranged components

A

Woven bone

40
Q

Lamellar bone: Multiple layers either _____ circumferential or in _____ ____ around a central canal

A

Parallel; concentric rings

41
Q

Another name for Haversian system

A

Osteon

42
Q

The complex of concentric lamellae, surrounding a central canal that contains small blood vessels, nerves and endosteum

A

Osteon

43
Q

Outer boundary of each Osteon is a layer called the _____ line that includes many more noncollagen proteins

A

Cement

44
Q

How central canals communicate with one another using ____ _____

A

Volkmann canals

45
Q

Numerous irregularly shaped groups of parallel lamellae; scattered among the intact osteons

A

Interstitial lamellae

46
Q

Long bones have parallel lamellae organized as multiple _____ circumferential lamellae immediately beneath the periosteum and fewer _____ circumferential lamellae around the marrow cavity

A

External; inner

47
Q

Nonlamellar and characterized by random disposition of type I collagen fibers

A

Woven bone

48
Q

The first bone tissue to appear in embryonic development and in fracture repair

A

Woven bone

49
Q

_______ ossification in which osteoblasts differentiate directly from mesenchyme and begin secreting osteoid

A

Intramembranous

50
Q

_______ ossification, in which a preexisting matrix of hyaline cartilage is eroded and invaded by osteoblasts, which begin osteoid production

A

Endochondral

51
Q

_____ bone is produced first and is soon replaced by stronger ______ bone

A

Woven; lamellar

52
Q

Most flat bones - skull, jaws, scapula, and clavicle - are formed embryonically by __________ ossification

A

Intramembranous

53
Q

Areas in which Osteoprogenitor cells arise, proliferate, and form incomplete layers of osteoblasts around a network of developing capillaries

A

Ossification centers

54
Q

Areas in which Osteoprogenitor cells arise, proliferate, and form incomplete layers of osteoblasts around a network of developing capillaries

A

Ossification centers

55
Q

________ ossification that takes place within hyaline cartilage

A

Endochondral

56
Q

Ossification first occurs within a bone _____ produced by _______ that differentiate within the peri_______ around the cartilage model ________

A

Collar; osteoblasts; perichondrium; diaphysis

57
Q

Step 2. The collar impedes diffusion of oxygen and nutrients into the underlying cartilage, causing local _________ to swell up (hypertrophy), compress the surrounding _______, and initiate its calcification by releasing ________ and alkaline phosphatase

A

Chondrocytes; matrix; osteocalcin

58
Q

Step 3. After Chondrocytes die, one or more blood vessels from the peri______ penetrate the bone collar, bringing osteo__________ cells to the porous central region

A

Periosteum; Osteoprogenitor

59
Q

Step 4. Newly formed ______ move into all available spaces and produce _____ bone

A

Osteoblasts; woven

60
Q

The process in the diaphysis forms the ______ ossification center, beginning in many embryonic bones

A

Primary

61
Q

Secondary ossification centers appear later at the ______ of the cartilage model

A

Epiphyses

62
Q

Both the primary and secondary ossification centers produce cavities that are gradually filled with ____ _____ and ______ of cancellous bone

A

Bone marrow; trabeculae

63
Q

With the primary and secondary ossification centers, two regions of cartilage remain: ______ cartilage and _______ plate/cartilage

A

Articular; epiphyseal

64
Q

Connects each epiphysis to the dialysis and allows longitudinal bone growth

A

Epiphyseal plate/cartilage

65
Q

Zone of ____ _____ is composed of typical hyaline cartilage

A

Resting cartilage

66
Q

In the ______ zone, cartilage cells divide repeatedly, enlarge and secrete more type ___ collagen and proteoglycans, and become organized into columns _______ to the long axis of the bone

A

Proliferative; II; parallel

67
Q

The zone of ______ contains swollen, terminally differentiated Chondrocytes, which compress the matrix and secrete collagen X which limits ________

A

Hypertrophy; diffusion

68
Q

In the zone of ____ _____, chondrocytes about to undergo apoptosis release matrix vesicles and _______ to begin matrix calcification by the formation of ___________ crystals

A

Calcified cartilage; osteocalcin; hydroxyapatite

69
Q

In the zone of _________, bone tissue first appears. Capillaries and _________ cells invade the now vacant chondrocytic ______

A

Ossification; Osteoprogenitor; lacunae

70
Q

An example of bone ______ is the ability of the positions of teeth in the jawbone to be modified by the lateral pressures produced by orthodontic applications

A

Plasticity

71
Q

Step 1. Blood vessels torn within the fracture release blood that ___ to produce a large fracture ______

A

Clots; hematoma

72
Q

Step 2. The hematoma is gradually removed by ________ and replaced by soft _________-like mass called ______ tissue

A

Macrophages; fibrocartilage; procallus

73
Q

Step 3. The fibrocartilage is gradually replaced by ______ bone that forms a hard _____

A

Woven; callus

74
Q

Step 5. Woven bone is replaced by ______ bone

A

Lamellar

75
Q

______ ______ raises low blood calcium levels by stimulating osteoclasts and osteocytes to resorb bone matrix and release Ca2+

A

Parathyroid hormone (PTH)

76
Q

PTH receptor occur on _______, which respond by secreting RANKL and other paracrine factors that stimulate _______ formation and activity

A

Osteoblasts; osteoclast

77
Q

________ reduce elevated blood calcium levels by targeting ______ to slow matrix resorption and bone turnover

A

Calcitonin; osteoclasts