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Anatomy > Cartilage & Bone > Flashcards

Cartilage & Bone Flashcards

Overview of common terms, structures, and formations found in the human skeletal system

0
Q

What is the Skeletal System?

A

Dynamic living tissues. bones, cartilage, ligaments, CT that stabilizes or connect to Bones.

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1
Q

What is the supporting framework for the soft tissues of the body?

A

Skeleton

skeletos=dried

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2
Q

Define cartilage.

What are the components?

A

-Semirigid CT.
-Weaker than bone BUT more flexible and resilient.
cells scattered through a matrix of protein fibers in ground substance

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3
Q

What are Chondroblasts?

A

(chondros=grit; blastos=germ)

chondrocyte cells that produce the matrix in cartilage.

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4
Q

What do lacunae hold?

A

Chondrocytes, Osteocytes

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5
Q

What are the functions of Cartilage?

A
  • Support soft tissue
  • provides gliding surface at articulation (joints), where two bones meet
  • model for formation later replaced by bone
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6
Q

What are the two growth patterns for cartilage?

A

Interstitial and Appositional

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7
Q

What is the name for internal growth of cartilage?

A

Interstitial

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8
Q

What is the name for external growth of cartilage?

A

Appositional

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9
Q

What’s the process for Interstitial Growth?

A

1) chondrocyte in lacunae go through mitosis
2) 2 new cells occupy lacunae
3) as cells synthesize & secrete new matrix
4) new cells push apart and reside in their own lacunae
* *New matrix=new chondrocyte

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10
Q

Describe the Appositional Growth Process

A

1) stem cells at internal edge perichondrium divide…
2) form a new stem cell & Committed Cell
3) committed cells differentiate into chondroblasts
4) chondroblasts, periphery of old cartilage, secrete new cartilage matrix.
5) Push apart & become chondrocytes in lacunae

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11
Q

When does Interstitial and Appositional growth occur?

A
  • Simultaneously.

- Interstitial growth ceases when cartilage matures, but reoccurs when cartilage is damaged

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12
Q

What tissue types are in bones?

Name them

A

ALL
-Bone Tissue: (Osseus CT) Primarily present.
-CT Proper: Periosteum
-Cartilage CT: articular cartilage
-Smooth Muscle Tissue: forming walls of blood vessels that supply bone
-Fluid CT: Blood
-Epithelial Tissue: lining the inside opening of blood vessels
Nervous Tissue: Nerves that supply bone

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13
Q

Define calcification

A
  • a process that impregnates something with calcium (or calcium salts)
  • makes bones rigid
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14
Q

What’s the functions of bones?

A
  • Support & Protect
  • Movement
  • Hemopoies
  • Storage of Minerals & Energy Reserves: store 90% of calcium & phosphate
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15
Q

Describe Hemopoies

A

Blood cell production in red bone marrow (contains stem cells form all formed elements in blood), located in some spongy bone & medullary cavity. As children mature, red bone marrow disintegrates and replaced by yellow bone marrow (fatty tissue)

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16
Q

Describe Long Bones

Where can they be located?

A

-Greater length than width.
-cylindrical diaphysis
-different sizes.
EX) legs, fingers, toes, palms

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17
Q

Describe Short Bones

Where can they be located?

A

-Length=Width.
-Exterior is Compact bone
-Interior is Spongy Bone.
EX) Carpals, Tarsals, Sesamoid bones, patella

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18
Q

Describe Flat Bones

Where can they be located?

A

-Parallel surfaces of compact bone with internally placed spongy bone.
-extensive surface for muscle attachment & protect underlying soft tissue
EX) Skull roof, shoulder blades, sternum

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19
Q

Describe Irregular Bones

Where can they be located?

A

-elaborate/complex shapes.

EX) vertebrae, ossa coxae, skull bones (ethmoid & sphenoid)

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20
Q

What are the 4 different types of bones?

A

Long, short, flat, irregular

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21
Q

Describe the medullary Cavity and where it’s located?

A
  • “marrow cavity”
  • hollow
  • in diaphysis
  • adults=yellow bone marrow
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22
Q

What part of the bone is long and provides leverage and support?

A

Diaphysis

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23
Q

What cartilage promotes movement, reduces friction, and absorbs shock on bone joints?

A

Articular Cartilage

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24
Q

Where is the Metaphysis located?

A

Between Epiphysis & Diaphysis

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25
Q

Epiphyseal (Growth) Plate

A

Hayline cartilage that continues growing and elongating the bone as a child. It turns into the Epiphyseal line as an adult.

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26
Q

What incomplete later of cells covers internal surface of bones?

A

Endosteum

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27
Q

What is the periosteum?

A

-tough outer sheath EXCEPT areas w/ articular cartilage
-Dense Irregular CT. tough outer fibrous, inner cellular layer
-perforating fibers
-protects, anchors BV and nerves to surface of bone, provides stem cells
(osteoprogenitor & osteoblasts) for width growth & fracture repair

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28
Q

What is the Endosteum?

A
  • incomplete later of cells covers internal surface of bones
  • osteoprogenitor cells, osteoblasts, & osteoclasts
  • active during growth, repair, & remodeling
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29
Q

Define perforating fibers

A

-perforating fibers: collagen fibers attaches periosteum to bone. perpendicular to diaphysis

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30
Q

Where do osteoprogenitor cells originate from?

A

menchyme

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31
Q

What 4 types of cells are found in bone CT?

A

Osteoprogenitor Cells, Osteoblasts, Osteocytes, osteoclasts

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32
Q

where do osteoclasts derive from?

A

-large, multinucleated, phagocyte, ruffled border where it contacts bone; increases surface area exposure

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33
Q

What bone cells derive from fused bone marrow

A

Osteoclasts

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34
Q

What’s the Bone resorption Process?

A
  • osteocytes secrete hydrochloric acid & dissolve calcium+phosphorus of matrix
  • lysosomes secrete enzymes & dissolve organic matrix
  • osteolysis occurs, ions enter tissue fluid & then blood
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35
Q

What process involves the release of stored calcium & phosphate from bone matrix?

A

osteolysis

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36
Q

Where are Osteoprogenitor Cells located?

How do they divide?

A
  • periosteum & endosteum

- “committed cell”+stem cell= Osteoblast

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37
Q

Describe Osteoblasts

A
  • (blasts=germ)
  • cuboidal structure
  • produce new bone and osteocytes
  • secrete Osteoid
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38
Q

Define Osteoid

A
  • Semi solid bone matrix

- calcium salt deposition= calcifies & hardens

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39
Q

Osteocytes

A
  • (cyt=cell)

- mature bone cells from osteoblasts stuck in their secreted matrix

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40
Q

What “shells” osteocytes in matrix?

A

lacunae

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41
Q

What bone cells remove matrix and add matrix?

A

osteoclasts remove matrix; osteoblasts add

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42
Q

What’s the amount of matrix composition of organic and inorganic material in bones?

A

1/3 organic to 2/3 inorganic

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43
Q

What is the organic material in matrix?

A

cells, collagen fibers, ground substance

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44
Q

What are the inorganic components of bone matrix?

A

Ca3(PO4)2+Ca(OH2)=Ca10(PO4)6(OH2)

Calcium phosphate+Calcium Hydroxide= Hydroxyapatite

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45
Q

Hydroxyapatite

A
  • hardens matrix

- includes other salts (calcium carbonate) & ions (sodium, magnesium, sulfate, fluoride in calcification process

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46
Q

What are the components of an Osteon? (4)

A
  • Central Canal,
  • Concentric Lamellae
  • Osteocytes
  • Canaliculi
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47
Q

What structures are NOT part of Osteon Proper? (3)

A
  • Perforating Canals
  • Circumferential Lamellae
  • Interstitial Lamellae
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48
Q

What is central to the osteon and hold BV & nerves supply to bone?

A

Central Canal

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49
Q

What are Concentric Lamellae?

A
  • (lamina=plate/leaf)
  • rings of Bone CT.
  • collagen fibers oriented in one direction=gives bones strength & resilience.
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50
Q

Describe Canaliculi?

A

(canalis=canal)

  • tiny, interconnecting lacuna channels, travel through lamellae,
  • communication, transfer minerals and waste
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51
Q

What structure connects central canales?

A

Perforating Canals: (Volkmann Canals)

**resemble central canals.

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52
Q

What lamellae are internal to periosteum and/or endosteum?

A

Circumferential Lamellae

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53
Q

Describe Interstitial Lamellae?

A
  • leftover disorbed osteons.

- incomplete/no central canal

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54
Q

What word defines spongy bone in between two compact bones in flat skull bone?

A

dipole: (diplous=double)

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55
Q

define trabeculae

A

open lattice of narrow plates of bone

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56
Q

Describe Spongy Bone

A

Porous

  • primarily internal. in epiphysis
  • hold parallel lamellae & trabeculae
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57
Q

What are osteons replaced by in spongy bone?

A

parallel lamellae

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58
Q

Describe parallel lamellae

A
  • osteocytes in lacunae
  • numerous canaliculi
  • criss-crossing
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59
Q

What process involves the formation & development of bone CT?

A

-Ossification/ Osteogenesis

  • (os=bone; facio=to make)
  • (genesis=beginning)
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60
Q

When is the skeleton formed with structural mesenchyme or hyaline cartilage?

A

12 weeks

61
Q

What’s the 1st step of Intramembranous Ossification?

A
  1. Ossification centers form within thickened regions of mesenchyme.
    - Starts 8th week
    - Holds Ossification Centers
62
Q

What’s the 2nd step of Intramembranous Ossification?

A
  1. Osteoid undergoes calcification
    a. osteoid+calcification=crystallization (hardening)
    b. calcification entraps osteoblasts in lacunae=osteocytes
63
Q

Describe Ossification Centers

A
  • mesenchyme cells divide=osteoprogenitor cells or osteoblasts (secrete osteoid).
  • centers multiply as osteoblasts increase
64
Q

What’s the 3rd step of Intramembranous Ossification?

A
  1. Woven bone and its surrounding periosteum form
  • mesenchyme thickens on woven bone=periosteum
  • bone expands w/ continuous osteoclast entrapments
  • Blood vessels grow and branch out
  • calcified trabeculae+intertrabecular spaces=spongy bone
65
Q

Describe Woven Bone

A

(primary bone) immature bone replaced by lamellae bone (secondary bone)

66
Q

What’s the 4th step of Intramembranous Ossification?

A
  1. Lamellar bone replaces woven bone, as compact & spongy bone form
68
Q

What ossification process involves “bone growth within a membrane”?

A

Intramembranous (Dermal) Ossification

EX) produces flat bones of skull, facial bones (zygomatic bone, maxilla), mandible (lower jaw), central part of clavicle (collarbone)

69
Q

Describe Dermal Ossification

A

(Intramembranous Ossification)
Dermal bone does not form from cartilage that then calcifies. Dermal bone is formed within the dermis and grows by accretion only – the outer portion of the bone is deposited by osteoblasts

70
Q

What are Ossification Centers?

A

mesenchyme cells divide=osteoprogenitor cells or osteoblasts (secrete osteoid). centers multiply as osteoblasts increase

71
Q

What is primary bone?

What is it replaced by?

A
  • Woven Bone

- Replaces Woven Bone

72
Q

What is secondary bone?

What does it replace?

A
  • Lamellae Bone

- Replaces Woven Bone

73
Q

How is periosteum made?

A

Mesenchyme thickens on woven bone

74
Q

What dense layer of vascular connective tissue envelopes the bones except at the surfaces of the joints?

A

Periosteum

75
Q

Endochondral Ossification

A

(endo=within; chondral=cartilage)
begins w/hyaline cartilage model
produces most skeletal bones

76
Q

What’s the 1st step to Endochondral Ossification?

What does it develope?

A
  1. The fetal hyaline cartilage model develops

- happens 8-12 weeks into development

77
Q

What’s the 2nd step to Endochondral Ossification?

A
  1. Cartilage calcifies, and a periosteal bone collar forms
78
Q

What’s the 3rd step to Endochondral Ossification?

A
  1. The primary ossification center forms in the diaphysis
79
Q

What’s the 4th step to Endochondral Ossification?

A
  1. Secondary Ossification centers from in the epiphysis
80
Q

What’s the 5th step to Endochondral Ossification?

A
  1. Bone replaces cartilage, except the articular cartilage and epiphyseal
81
Q

What’s the 6th step to Endochondral Ossification?

When does this process occur?

A
  1. Epiphyseal plates ossify and form epiphyseal lines

- Ages 10-25

82
Q

What forms periosteal bone collar?

A

Hardened Osteoid

83
Q

What happens during primary ossification?

A

bone replaces cartilage in hyaline models

84
Q

During Endochondral Ossification, when are most primary ossification centers developed?

A

12th week

85
Q

During Endochondral Ossification, when does secondary ossification occur?

A

Birth-Childhood

86
Q

What are the Zones of Epiphyseal Plate Morphology?

*There are 5

A
  1. Zone of Resting Cartilage
  2. Zone of Proliferating Cartilage
  3. Zone of Hypertrophic Cartilage
  4. Zone of Calcified Cartilage
  5. Zone of Ossification
87
Q

Describe Zone of Resting Cartilage

A
  1. Zone of Resting Cartilage
    - farthest from medullary cavity, closest to epiphysis
    - small chondrocytes throughout matrix
    - mature/healthy cartilage
    - secures epiphysis to epiphyseal plate
88
Q

Describe Zone of Proliferating Cartilage

A
  1. Zone of Proliferating Cartilage

- chondrocyte rapid mitotic cell division,enlarge,stack in columns of flattened lacunae

89
Q

Describe Zone of Hypertrophic Cartilage

A
  1. Zone of Hypertrophic Cartilage
    - chondrocytes stop dividing>hypertrophy
    - lacunae walls thin as chondrocytes resorb matrix
90
Q

Describe Zone of Calcified Cartilage

A
  1. Zone of Calcified Cartilage
    - narrow, few cells thick
    - Minerals deposited in matrix through columns of lacunae
    - calcification kills chondrocytes= matrix not transparent
91
Q

Describe Zone of Ossification

A
  1. Zone of Ossification
    - lacunae walls break down=longitudinal channels
    - capillaries & osteoprogenitor cells from medullary cavity invade spaces
    - new matrix deposited
92
Q

What is “internal” bone growth?

A

Interstitial Growth

93
Q

Describe interstitial bone growth process

A
  • epiphyseal plate- pushing zone2&3
  • bone production zone5
  • maturity=epiphyseal cartilage slows+osteoblast activity accelerates=epiphyseal narrows
  • Epiphyseal line=growth stopped
94
Q

What is “external” bone growth?

A

Appositional Growth

95
Q

Describe appositional bone growth process

A
  • periosteum forms

- bone resorbed by osteoclasts>Bone deposited by osteoblasts

96
Q

Describe the bone remodeling process

A
  • deposition of new bone CT & resorption of old bone CT
  • regulates calcium & phosphorus levels
  • stimulated by stress of bone
  • periosteal & endosteal surfaces
  • 20% adult skeleton replaced yearly
  • compact bone replaced slower than spongy
97
Q

Where do blood vessels enter through to the bone?

A

Periosteum

98
Q

Describe Nutrient BV

A

(Nutrient Artery & Nutrient Vein)

  • enters & leaves through foramen
  • supply diaphysis of long bone
  • branch externally along shaft towards epiphyses and into central cavity of osteons within compact bone and the marrow cavity
99
Q

Describe Metaphyseal BV

A

(Metaphyseal Artery & Vein)

  • provide nutrients to diaphyseal side of the epiphyseal plate
  • where bone ossification forms bone CT to replace epiphyseal cartilage
100
Q

Describe Epiphyseal BV

A

-provide to epiphysis of bone

metaphyseal & epiphyseal connect when Epiphyseal line forms

101
Q

Describe Periosteal BV

A
  • external circumferential lamellae & superficial osteons

- BV enter diaphysis and perforating canals

102
Q

What’s Somatropin?

What does it do?

A
  • Growth Hormone
  • stimulates the production of hormone Somatomedin in liver
  • promotes epiphyseal plate growth
103
Q

What hormone does the thyroid gland secrete?

A

Thyroid Hormone & Calcitonin

104
Q

What influences basal metabolic rate of bone growth?

A

Thyroid Hormone

105
Q

What hormone influences calcium deposition in bone and inhibits osteoclast activity?

A

Calcitonin

106
Q

What hormone increases blood calcium levels by encouraging bone resorption by osteoclasts?

A

Parathyroid Hormone

107
Q

What hormone does the parathyroid secret?

A

Parathyroid Hormone

108
Q

What are the sex hormones?

A

Estrogen (F) & Testosterone (M)

109
Q

How do sex hormones affect bone growth?

A
  • increase osteoblasts in epiphyseal plate

- puberty=beginning of end of growth

110
Q

How does Vitamin A effect bone growth?

A

Activates Osteoblasts

111
Q

How does Vitamin C (asorbic acid) effect bone growth?

A

Promotes collagen production

112
Q

How does Vitamin D effect bone growth?

A
  • Promotes obsorption of calcium & phosphate into blood

- Helps w/ calcification of bone

113
Q

What hormone is secreted by the adrenal cortex?

A

Glucocorticoids

114
Q

What happens if levels of glucocorticoids is cronically low?

A

bone resorption occurs & significant bone mass is lost

115
Q

How does exercise effect bones?

A
  • stress=bone remodeling & calcitonin
  • mineral salts+collagen= strengthening
  • Increased Bone Mass
116
Q

What is a break in a bone called?

A

Fracture

117
Q

How is a fracture named?

A

stress, trauma, or pathology & amount of Soft Tissue Damage

118
Q

What fracture occurs on weight bearing bones due to recent/ repetitive activity?

A

Stress Fractures

EX) pelvis & lower-limbs of Runners

119
Q

What fracture is caused by excessive impact/stress to bone?

A

Traumatic Fracture

120
Q

What fracture is caused by the weakening of bone due to disease?

A

Pathological Fracture

121
Q

What is a simple fracture and how long does it take to heal?

A
  • DOESNT penetrate skin

- 2-3months

122
Q

What fracture does penetrate the skin & underlying tissues?

A

Compound fracture

123
Q

How does a fracture repair itself?

4 steps

A
  1. A fracture hematoma forms
  2. A fibrocartilaginous (soft) callus forms
  3. A hard (bony) callus forms
  4. The bone is remodeled
124
Q

How long does a hard callus last?

A

3-4 months

125
Q

What is clotting called during fracture repair?

A

Fracture Hematoma

126
Q

How long does a fibrocartilaginous callus last?

A

3 weeks

127
Q

What condition causes bone mass to become reduced enough to compromise normal function?

A

Osteoporosis

128
Q

What is refered to as “brittle bone disease”?

A

osteogenesis imperfecta

129
Q

What are the 4 articulating surface structures called?

A

Condyle
Facet
Head
Trochlea

130
Q

What is a large, smooth, rounded articulating structure called?

A

Condyle

131
Q

What is a small, flat, shallow articulating surface called?

A

Facet

132
Q

What is a prominent, rounded epiphysis called?

A

Head

133
Q

What is a smooth, grooved, pulley-like articular process called?

A

Trochlea

134
Q

What are the 3 Depressions called?

A

Alveolus (alveoli)
Fossa (fossae)
Sulcus

135
Q

What is a deep pit or socket in the maxillae or mandible called?

A

Alveolus

136
Q

What is a flattened or shallow depression called?

A

Fossa

137
Q

What is a narrow grove called?

A

Sulcus

138
Q

What are the 9 projections for tendons & ligament attachments?

A

Crest, Epicondyle, Line, Process, Ramus (rami), Spine, Trochanter, Tubercle, Tuberosity

139
Q

What is a narrow, prominent, ridgelike projection called?

A

Crest

140
Q

What projection is adjacent to a condyle?

A

Epicondyle

141
Q

What is a low ridge called?

A

Line

142
Q

What are any marked bony prominence called?

A

Process

143
Q

What are angular extensions of a bone relative to the rest of the structure?

A

Ramus (rami)

144
Q

What is a pointed slender process called?

A

Spine

145
Q

What massive, rough projection is found only on the femur?

A

Trochanter

146
Q

What is a small, round projection called?

A

Tubercle

147
Q

What is a large, rough projection called?

A

Tuberosity

148
Q

What are the 4 openings/spaces that can be found on a human skeleton?

A

Canal
Fissure
Foramen (foramina)
Sinus

149
Q

What is a passageway through a bone called?

A

Canal

150
Q

What is a narrow, slitlike opening through a bone called?

A

Fissure

151
Q

What is a rounded passageway through a bone called?

A

Foramen

152
Q

What is a cavity or hollow space in a bone called?

A

Sinus

Anatomy (10 decks)

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