Cartilage and Bone Flashcards
(132 cards)
1
Q
What is a specialized connective tissue?
A
Cartilage
2
Q
What are the functions of cartilage?
A
Bears mechanical stresses without permanent distortion.
3
Q
What is a framework to support soft tissues e.g., ears, nose?
A
Cartilage
4
Q
Which types of cartilage is responsible for shock-absorbing and friction-free sliding area for joints?
A
Hyaline cartilage
5
Q
Cartilage facilitates bone movements, this is done through which method?
A
Endochondral ossification method
6
Q
Cartilage is essential for development and growth of ______.
A
Long bones
7
Q
What are the 3 types of cartilages?
A
Hyaline, elastic, and fibrocartilage (not fibrous!).
8
Q
What is the variation between the 3 types of cartilages?
A
Matrix composition varies.
9
Q
What are the cells called in cartilage?
A
Chondrocytes
10
Q
Chondrocytes that are located in the matrix cavities is called?
A
Lacunae
11
Q
Chondrocytes synthesize and produce what?
A
Extracellular matrix
12
Q
What are the principle macromolecules? (4)
A
Collagen, hyaluronic acid, proteoglycans, and glycoproteins.
13
Q
What is the largest and most ubiquitous GAG?
A
Hyaluronic acid
14
Q
Physical properties of extracellular matrix depends on the chemical interactions between _____ and _____.
A
Collagen/elastic fibers and GAG-proteoglycans.
15
Q
High content of water bound to the GAG chains allows for a _____.
A
Semi-rigid consistency
16
Q
What is the layer of dense connective tissue containing nerves, vessels and lymphatics surrounding the cartilage called?
A
Perichondrium
17
Q
What is the purpose of perichondrium?
A
An interface between cartilage and surrounding tissue.
18
Q
Perichondrium is absent around what type of cartilage?
A
Articular cartilage
19
Q
Is cartilage vascular or avascular?
A
No, it is avascular!
20
Q
How are cartilages that contains perichondrium being nourished?
A
From capillaries in capillaries in the perichondrium.
21
Q
How are articular cartilage being nourished and why?
A
Through synovial fluid from joint capsules.
B/C articular cartilage don’t contain perichondrium.
22
Q
Does cartilage contain any lymphatic vessels?
A
No
23
Q
Does cartilage contain any nerves?
A
No
24
Q
What is the most common type of cartilage found in the body?
A
Hyaline cartilage
25
Where are hyaline cartilage found? (4)
- Articular surfaces
- Respiratory system structures
- Ventral ends of ribs
- Epiphyseal plates
26
What are the cells called in cartilage?
Chondrocytes
27
Can chondrocytes be in isogenous groups (produced by mitosis)?
Yes
28
What is the function of chondrocytes? (2)
Synthesize collagen and matrix molecules
29
What is perichondrium, and does it contain vessels?
Covering of dense connective tissue.
| Yes, contains vessels from which nutrients diffuse.
30
What type of collagen does perichondrium contain?
Type 1 collagen
31
What are the 2 cells that perichondrium contain?
Fibroblasts and chondroblasts.
32
What is perichondrium essential for? (2)
Growth and maintenance of cartilage
33
What type of collagen does hyaline cartilage have?
Type 2
34
What type of collagen does the matrix have in hyaline cartilage?
Type 2 collagen
35
Type 2 collagen fibrils are embedded in ______ linked to hyaluronic acid.
Hydrated gel of proteoglycans
36
In the matrix, what binds to the collagen fibrils?
Chondroitin sulfate
37
Glycoproteins (chondronectin) are structurally _____.
Multiadhesive
38
Intermittent cartilage compression and decompression (pumping action) helps transport _____ and _____ in the matrix.
Water and solutes
39
Regulation of cartilage growth is done by?
Growth hormone (somatotropin)
40
Where are elastic cartilage found? (4)
Auricle of ear, external auditory canals, eustachian tubes, epiglottis.
41
Elastic cartilage's matrix is similar to _____ but addition of _____.
Hyaline cartilage; elastic fibers (more coarse, larger)
42
Chondrocytes in elastic cartilage are more _____ and _____.
Abundant and larger.
43
Does elastic cartilage have perichondrium?
Yes, it does.
44
Where are fibrocartilage found?
IVDs and pubic symphysis.
45
Fibrocartilage is a combination of ______ (type 2 collagen) and ______ (type 1 collagen) with gradual transitions between the two.
Hyaline cartilage (type 2 collagen); Areas of dense connective tissue (type 1 collagen).
46
Chondrocytes occur in aligned _____ groups or singly in long rows separated by large areas of bundles of ______.
Isogenous; Collagen fibers
47
Does fibrocartilage have perichondrium?
No!
48
In fibrocartilage, is proteoglycans a scarce resource?
Yes
49
Proteoglycans are scarce so matrix is _____.
Acidophilic
50
Chondrogenesis contains______ cells.
Mesenchymal
51
Superficial mesenchyme will form ______.
Perichondrium
52
Mitotic activity produces a dense cellular tissue of ______.
Chondroblasts
53
Chondroblasts become separated from each other as they produce the ______.
Matrix
54
The matrix becomes larger as it becomes ______.
Hydrated
55
Chondroblasts form isogenous groups within the matrix but when mitotic activity ceases, the chondrocytes make more _____ and become ______.
Matrix; Pushed apart
56
Once isogenous groups within the matrix is formed, further growth occurs by: (2)
Interstitial and appositional
57
What is interstitial growth?
Mitosis of chondroblasts within lacunae.
58
What is appositional growth?
Differentiation of progenitor cells in the perichondrium to form new chondroblasts.
59
Bone is a specialized connective tissue. What are the functions? (5)
- Supports structures
- Protects organs
- Stores bone marrow
- Reservoir for mineral
- Allows for body movements
60
Is bone vascularized?
Yes, very well vascularized.
61
Are bones metabolically active or inactive?
Metabolically active
62
What are bones consists of?
Calcified matrix and cells.
63
What are the cells found in bone? (3)
Osteoblasts, osteocytes, and osteoclasts.
64
Where are osteoblasts derived from?
Osteoprogenitor cells
65
Function of osteocytes?
Maintain matrix
66
Function of osteoclasts?
Invoved in bone resorption and remodeling.
67
Where are osteoblasts located?
Located at bone tissue surfaces.
68
Synthesize and deposit organic components of bone matrix. Which cell is this?
Osteoblast
69
New (uncalcified) matrix called osteoid, is formed by the process of bone _____ growth.
Appositional
70
Process of appositional growth is completed when ______ are added and bone is formed.
Calcium salts
71
What does receptors for parathyroid hormones release?
Osteoclast stimulating factor (OSF)
72
Function of osteocytes?
Maintain matrix; help regulate bone remodeling.
73
Osteocytes are surrounded by _____ and located (singly) in a _____.
Matrix; Lacuna
74
Cytoplasmic processes are housed in_______ where exchange of metabolites occurs with other cells.
Matrix canaliculi
75
The cytoplasmic processes act as sensors detecting _____ on bone.
Mechanical stresses
76
This bone cell is very large, multinucleated; ruffled border if active.
Osteoclasts
77
Osteoclasts are located in depression of resorbed bone, this is also know as?
Howship's lacunae (resorption cavities)
78
What is the function of osteoclasts?
Bone resorption during bone growth and remodeling.
79
Osteoclasts also digest collagen; dissolve ______.
calcium salt crystals
80
Osteoclasts has receptors for _____(from thyroid gland) and for _____.
Calcitonin; OSF
81
Bone matrix contains _____ and _____.
Inorganic matter and organic matter.
82
Inorganic matter contains? (4)
Calcium, phosphorus, bicarbonate, magnesium.
83
What does calcium and phosporus form in bone matrix?
Hydroxyapatite crystals
84
Organic matter in bone matrix have what type of collagen?
Type 1 (90%)
85
What is found in organic matter in bone matrix?
Ground substance of proteoglycan aggregates and multiadhesive glycoproteins
86
Mixture of minerals with collagen fibers produces the ______ and ______ of bone.
Hardness and resistance
87
Outer layer of collagen fibers and fibroblasts covering the bone is?
Periosteum.
88
______ fibers penetrate the bone matrix and bind periosteum to bone.
Sharpey's (perforating) fibers
89
What is found in the inner layer of periosteum?
Osteoprogenitor cells and osteoblasts
90
What is the function of coverings of bone surface? (2)
Provide nutrition for osseous tissue.
| Supply osteoblasts for repair or appositional bone growth.
91
What lines internal cavities (and trabeculae) within bone?
Endosteum
92
Endosteum has 1 layer of flat _____, _____, and some _____.
Flat osteoprogenitor cells, osteoblasts, and some connective tissue.
93
What are the two types of bones?
Compact (cortical) and Spongy
94
Dense areas without cavities is which type of bone?
Compact (cortical) bone
95
Areas of trabeculae forming interconnecting cavities is which type of bone?
Spongy (cancellous) bone
96
The ends (epiphyses) have _____- covered by (thin) compact.
Spongy bone
97
The shaft (diaphysis) are compact bone with some spongy bone lining the ______.
Marrow cavity
98
Primary bone is known as? Secondary bone is known as?
Primary (woven)
| Secondary (Lamellar)
99
-No lamellar organization
-Random array of collagen fibers
-First to appear during development
-First in fracture repair processes
-Replaced by secondary bone
(PRIMARY OR SECONDARY BONE?)
Primary (woven)
100
-Collagen fibers are highly organized and arranged in lamellae (layers) of calcified matrix
-Lamellae surrounding a canal containing a nerve, vessels, and loose connective tissue is a Haversian system (osteon)
-Between or within lamellae are lacunae
80% is compact and 20% is spongy
(PRIMARY OR SECONDARY BONE?)
Secondary (Lamellar)
101
Making new bone, remodel, then becomes secondary bone.
| Primary or secondary bone?
Primary
102
Lamellae sounds canal is called a Haversian system or osteon. This occurs in primary or secondary bone?
Secondary
103
Compact bone is composed of thin layers or lamellae of bone and form an _____.
Osteon
104
Organized lamellae greatly increases the _____ of bone
Strength
105
Lamellae also are organized as outer and inner ______.
Circumferential lamellae
106
Lacunae contain one osteocyte which interconnects with others through _____ within canaliculi.
Processes
107
Osteocytes are supplied by vessels in the _____.
Central canal
108
Central canals communicate with marrow cavity, periosteum, and each other via _____.
Transverse Volkman’s (aka perforating) canals
109
- Occurs w/in condensations of embryonic mesenchymal cells
- Differentiate into osteoblasts (takes place in primary ossification center) which surround capillaries
- Osteoid matrix is produced and then calcified forming trabeculae (islands of bone) of woven (primary) bone; its surface is surrounded by osteoblasts
(Intramembranous or endochondral ossification?)
Intramembranous ossification (most flat bones of skull)
110
Trabecular growth in intramembranous ossification, leads to the fusion of adjacent ossification centers which gradually produce layers of _____ that encloses cancellous bone
Compact bone
111
During endochondral ossification, _____ is vascularized & _____ formed.
perichondrium; bone collar
112
Primary ossification center is produced in which type of ossification?
Endochondral ossification
113
Osteoclasts resorb calcified cartilage/bone complex and enlarge cavity which fills with bone marrow; bone replaces cartilage along diaphysis.
This process is to form what?
Primary ossification center
114
(Endochondral ossification)
| At epiphysis, _____ ossification center appears; no bone collar.
Secondary
115
During remodeling of secondary ossification center, cavity is produced that fills with?
Bone marrow
116
What are the two areas of cartilage that remain during endochondral ossification?
Articular and epiphyseal
117
What is epiphyseal cartilage responsible for?
Bone growth in length
118
There are how many zones in epiphyseal cartilage?
5
119
1st zone in epiphyseal cartilage is known as?
Zone of resting cartilage
120
2nd zone in epiphyseal cartilage is: zone of proliferating cartilage. What happens here?
Chondrocytes aligned as aggregates in lacunae
121
3rd zone in epiphyseal cartilage is: zone of hypertrophic cartilage. What happens here?
Cells enlarge; matrix compressed into bands
122
4th zone in epiphyseal cartilage is: zone of calcified cartilage. What happens here?
Cells calcify the matrix (hydroxyapatite crystals formed); undergo apoptosis
123
5th zone in epiphyseal cartilage is: zone of ossification cartilage. What happens here?
Vessels invade region; osteoblasts deposit osteoid on calcified spicules of cartilage forming woven bone.
124
In bone growth and remodeling, new bone development is balanced with bone _____.
Resorption
125
In bone growth and remodeling,_____systems are continually being replaced
Harversian
126
Normal bone growth is dependent on sufficient _____, _____, _____.
Proteins, minerals, and vitamins.
127
Normal bone growth is also dependent on hormones such as? (3)
Growth, thyroid, estrogen/testosteron
128
Bone is capable of repair because it contains _____ cells in the periosteum, endosteum, and bone marrow and is very well vascularized.
Osteoprogenitor
129
Bone contains ___% of body's total calcium in crystals.
99%
130
Metabolic role of bone: Transfer calcium from crystals to _____ and into blood.
Interstitial fluid
131
Which hormone stimulates osteoblasts to secrete osteoclast-stimulating factor thus promoting resorption?
Parathyroid hormone
132
Which hormone inhibits osteoclast activity?
Calcitonin
