Osteochondrogenesis Flashcards
(85 cards)
1
Q
Methods of bone histogenesis
A
intramembranous and endochondral bone formation
2
Q
bone remodeling
A
the combination of bone formation and resorbtion
3
Q
True or false: Bone remodeling occurs throughout life.
A
True
4
Q
True or false: Remodeling occurs more slowly in primary bone than secondary bone
A
False
5
Q
Bone is a buffer for ____.
A
calcium
6
Q
Calcium concentration is determined by ____.
A
The rate at which calcium leaves and enters bone.
7
Q
_____ form an erosion tunnel, and after about two weeks they undergo _____, and _____ start formation of new _____. (Remodeling)
A
Osteoclasts, apoptosis, osteoblasts, osteon
8
Q
Remodeling occurs inside ____ bone and ____.
A
compact, bone surfaces
9
Q
When new bone is laid down on an eroding surface, a thin layer of ______ is first produced. This layer is called _____.
A
cementing substance, a cementing or reversing line
10
Q
The cementing line is _____ and has little ____.
A
highly mineralized, collagen
11
Q
About ____% of bone turns over per year in adults.
A
10
12
Q
Osteoclasts come from ____ .
A
hematopoietic stem cells
13
Q
Osteoblasts come from _____.
A
Mesenchymal stem cells
14
Q
Signaling from _____ or ____ act on hematopoietic stem cells to form _____.
A
osteoblast precursors, lining cells, osteoclasts
15
Q
After a period of resorption, _____ then lay down bone, and some will be trapped to become _____.
A
osteoblasts, osteocytes
16
Q
Flat bone formation occurs in highly _____ _____ .
A
vascular, mesenchymal tissue
17
Q
Flat bone examples
A
skull, facial bones, mandible, clavicle, pelvis
18
Q
Regulators of flat bone formation
A
patterning signals from polypeptides of Wnt, hedgehog, fibroblast growth factor, and transforming growth factor beta families
19
Q
Mesenchymal cells condense into _________, differentiate into ____ and begin secreting ______ . (In flat bone formation)
A
primary ossification centers, osteoblasts, osteoid collagen
20
Q
osteoid collagen
A
collagen with randomly oriented collagen fibrils
21
Q
In flat bone formation, the first bone formed is called
A
woven bone
22
Q
With _____, osteoblasts trapped in the matrix become ____. Small spicules of developing bone unite to form ____. (In flat bone formation)
A
calcification, osteocytes, trabeculae
23
Q
Fusion of bony _____ produces ____ bone. Blood vessels invade and other undifferentiated _____ cells give rise to bone marrow. (In flat bone formation)
A
trabeculae, spongy, mesenchymal
24
Q
Areas of mesenchymal tissues that do not ossify differentiate into ___ and ____. (In flat bone formation)
A
periosteum, endosteum
25
Woven bone initially formed from ________ will convert to _____ bone in the ____ layers. The ____ layers remains as spongy bone (diploe). (In flat bone formation)
irregular osteoid collagen matrix, lamellar, outer, inner
26
Name the structures shown from left to right
mesenchyme,
collagen,
osteoid,
osteoblasts,
trabeculae,
osteocytes
27
Label
1) trabeculae
2) Developing flat bone
3) osteoblasts
4) Primary Ossification Center
28
Endochondral bone formation
Long bone formation
29
\_\_\_\_\_\_ serves as a small model for the bone and as a scaffold for bone development. (Endochondral bone formation)
Hyaline cartilage
30
Endochondral bone formation occurs in ___ stages: Development of ____ and \_\_\_\_. (Endochondral bone formation)
2,
primary (centers of ossification) and secondary centers of ossification
31
The primary center of ossification develops at the ______ of the _____ of the \_\_\_\_\_\_\_. (Endochondral bone formation)
midriff,
diaphysis,
cartilaginous model
32
\_\_\_\_\_ of perichondrium at the site transforms _______ to \_\_\_\_\_. They then differentiate into osteoblasts. Perichondrium is now called the \_\_\_\_\_. (Endochondral bone formation)
Vascularization,
chondrogenic cells,
osteoprogenitor cells,
periosteum
33
Osteoblasts produce the ______ (deep to the periosteum) on the surface of the _____ model by intramembranous bone formation. (Endochondral bone formation)
subperiosteal bone collar,
cartilaginous
34
The chondrocytes in the subperiosteal bone collar region become ____ and secrete ___ and \_\_\_\_. The _____ begins to calcify. (Endochondral bone formation)
hypertrophic,
collagen X,
vascular endothelial growth factor
cartilage matrix
35
The _____ inhibits nutrient diffusion and hypertrophied ____ die. _____ become confluent forming a primitive marrow cavity. (Endochondral bone formation)
calcified cartilage matrix,
chondrocytes,
lacunae
36
\_\_\_\_ create perforations in the bone collar. This permits ___ to enter the primitive marrow cavity in the C-model. ____ in the walls of these spaces then becomes calcified.
Osteoclasts,
periosteal buds (blood vessels, osteoprogenitor cells and mesenchymal cells),
Cartilage
37
What is contained in periosteal buds?
Blood vessels, osteoprogenitor cells and mesenchymal cells
38
Osteoid
Bone matrix
39
\_\_\_\_\_\_ is made and calcified on the surface of calcified cartilage and forms a \_\_\_\_. (Endochondral bone formation)(primary ossification center)
bone matrix,
calcified cartilage-calcified bone complex
40
Calcified cartilage stains \_\_\_.
basophilic
41
Calcified bone stains \_\_\_\_.
acdiophilic
42
Subperiosteal bone collar thickens and elongates toward the \_\_\_\_\_. (Endochondral bone formation)
epiphyses
43
\_\_\_\_ begin to reabsorb the calcified cartilage-calcified bone complex. This enlarges the primitive \_\_\_\_\_. (Endochondral bone formation)
Osteoclasts,
marrow cavity
44
This is a picture of \_\_\_.
A primary ossification center
45
What is labeled with the black line?
A growth plate
46
Where do secondary centers of ossification occur?
They develop at epiphyses after diaphyseal ossification centers are well established
47
When do secondary centers of ossification form?
(After diaphyseal ossification centers are well established) When osteoprogenitor cells invade the epiphyses and differentiate into osteoblasts
48
When the epiphyses are filled with bone tissue, cartillage is found in \_\_\_\_\_.
(Two areas)
articular surfaces and the epiphyseal plates
49
True or false: In secondary centers of ossification, articular cartilage contributes to bone formation.
False
50
Diaphyseal and epiphyseal bone become continous at about _____ of age. This connects the two epiphyseal \_\_\_\_.
20 years,
marrow cavities
51
\_\_\_\_\_ plates continues to grow. New cartilage is added to the _____ end while being replaced at the ____ end.
Epiphyseal,
epiphyseal,
diaphyseal
52
What are the epiphyseal plate zones?
Zone of reserve, Zone of proliferation, Zone of cell hypertrophy, zone of calcification, zone of ossification (reabsorption)
53
Zone of reserve
small, randomly arranged, inactive chondrocytes
54
Zone of proliferation
(Interstitial growth)
Region of rapid mitotic divisions, gives rise to rows of isogenous cell groups. Cartilage grows away from advancing bone
55
Zone of cell hypertrophy
region where the chondrocytes are enlarged
56
Zone of calcification
region where remnants of cartilage matrices become calcified and chondrocytes die
57
Zone of ossification
(Reabsorption)
Where bone is made upon the calcified cartilage, followed by reabsorption of the calcified bone-calcified cartilage complex
58
Zone containing small, randomly arranged, inactive chondrocytes
Zone of reserve
59
Zone containing region of rapid mitotic divisions that gives rise to rows of isogenous cell groups.
Zone of proliferation
60
Region where the chondrocytes are enlarged
Zone of cell hypertrophy
61
region where remnants of cartilage matrices become calcified and chondrocytes die
zone of calcification
62
Where bone is made upon the calcified cartilage, followed by the reabsorption of the calcified bone-calcified cartilage complex
Zone of ossification (reabsorption)
63
Label the regions and determine the direction of growth
red: proliferative (zone of proliferation)
green: zone of reserve
blue: hypertrophic
black: Calcified cartilage (zone of ossification)
direction: Upwards
64
In the region of \_\_\_\_, blood vessels penetrate the region and bring in _____ and begin the process of remodeling calcified cartilage into bone.
calcified cartilage,
osteoprogenitor cells
65
Periosteal buds penetrate the _____ and erode away the \_\_\_\_\_
epiphysial cartilage,
calcified cartilage
66
Proliferating chondrocytes secrete \_\_\_\_, which stimulates chondrogenic periosteal cells to secrete \_\_\_\_\_.
indian hedgehog protein,
parathyroid hormone related protein
67
\_\_\_\_\_ secrete indian hedgehog protein, which stimulates ____ to produce parathyroid hormone-related protein
Proliferating chondrocytes,
periosteal cells
68
Parathyroid hormone related protein stimulates \_\_\_\_\_\_\_, but also inhibits \_\_\_\_\_.
reserve zone chondrocytes,
proliferative zone chondrocyte hypertrophy
69
Hypertrophic zone chondrocytes secrete \_\_\_\_\_.
type X collagen and VEGF
70
\_\_\_\_\_ secrete type X collagen and VEGF.
Hypertrophic zone chondrocyte
71
Fracture damages ______ and is accompanied by localized ______ and \_\_\_\_.
bone matrix, bone cells, and blood vessels,
hemorrhaging and blot clot formation
72
Steps of healing of a fracture
1. Proliferation of osteoprogenitor cells from the periosteum and endosteum surrounding the fracture.
2. A cellular tissue surrounds the fracture and penetrates between the ends of the damaged bone.
3. A callus forms both internally and externally at a fracture site.
4. Fibrous connective tissue and hyaline cartilage are formed in this fracture zone.
5. Endochondral bone formation replaces the cartilage with primary (woven) bone.
6. The irregularly arranged trabeculae of primary bone join the ends of the fractured bone, forming a bony callus.
7. The primary bone is reabsorbed and replaced with secondary (lamellar) bone as the fracture heals
73
Hairline fractures heal via _____ that occurs at the \_\_\_\_\_\_.
intramembranous bone formation,
periosteal surface
74
Types of joints
Diarthroses, synarthroses, amphiarthroses
75
Synarthroses joint
Example
immoveable joint, composed of connective tissue, cartilage, or bone
Unite the first rib to the sternum and connect skull bones
76
Amphiarthroses
Allow slight movement,
ex. intervertebral disk
77
Diarthroses joint
Aka synovial joint, permits maximum movement, unites long bones
Surrounded by a 2-layered capsule, encloses and seals the articular cavity, contains synovial fluid
78
Synovial fluid (composition)
colorless, viscous fluid rich in hyaluronic acid and proteins
79
Diarthroses joints have ___ layers. The _____ layer is a fibrous layer of \_\_\_\_. The ______ layer (also known as the ____ membrane), is lined by ___ to ____ cells on the internal surface.
2,
external (fibrous) capsular layer,
dense connective tissue,
Internal (synovial) capsular layer,
synovial,
squamous,
cuboidal
80
Type-A cells
phagocytic cells that have a well-developed golgi complex and many lysosomes
81
Type-B cells
resemble fibroblasts, have a well-developed rER; probably secrete synovial fluid. Nutrients diffuse to hyaline cartilage from synovial fluid
82
Osteopetrosis
a hereditary disease that displays abnormal osteoclast function. Bones are brittle and break easily. Most bone is woven bone and not lamellar due to lack of remodeling. Marrow cavity not developed.
83
Albers-Schonberg disease
Aka marble bone disease
It is a form of osteopetrosis in which bones are brittle and break easily. There is a lack of remodeling. There is a deficiency in carbonic anhydrase II. Osteoclasts can't accumulate H+ in Howship's lacunae to activate acid requiring lysosomal enzymes
84
Osteoporosis
Loss of bone mass (primary trabecular)
Postmenopausal osteoporosis mainly has normal rate of resorption, but decreased bone formation
85
Rheumatoid arthrtitis
Starts as an inflammatory reaction in synovial tissue
Pathogenesis involves activation of CD4+ T cells (unknown antigen). The T cells produce IL-15 which stimulates synovial macrophages to produce proinflammatory cytokines (TNF-alpha, IL-1, IL-6) and metalloproteases
