Chp 6 Skeletal System Flashcards
1
Q
What composed the skeletal system (SS)?
A
- Bones of Skelton
- Cartilage
- Ligaments
- Connective Tissue
2
Q
What are the 5 primary functions of the skeletal system?
A
- Support
- Storage minerals and lipids
- Blood cell production
- Protection
- Leverage
3
Q
What does the SS support?
A
- Entire body
* A framework for the attachment of soft tissue
4
Q
What minerals and lipids does SS store?
A
- Calcium (most abundant)
* Yellow bone marrow
5
Q
Where are the cells produced in SS?
A
• Red bone marrow
6
Q
How does the SS provide protection?
A
- skeletal structures surround many soft tissues and organs
* ex. Ribs protect the lungs and heart
7
Q
What does leverage of the SS mean?
A
• force generated by the Skeletal muscles that can change the magnitude and direction
8
Q
How are bones classified?
A
• Shape
• Internal tissue organization
-Compact, spongy
• Bone markings
9
Q
What are the 6 bone shapes?
A
- Sutural bones
- Irregular bones
- Short bones
- Flat bones
- Long bones
- Sesamoid bones
10
Q
How are suture bones?
A
- small
- irregular bones
- “Wormain bones”
11
Q
Where can you find Suture Bones?
A
• Between the flat bones of the skull
12
Q
How are Irregular bones??
A
- Complex shapes
* notches and processes
13
Q
Where can you find Irregular bones?
A
- examples include
- Vertebrae
- Coxal bones
- Pelvic bones
14
Q
How are short bones?
A
- similar in length and width
* roughly cubed shaped
15
Q
What are some examples of short bone?
A
- Carpals
* Tarsals
16
Q
How are flat bones?
A
- Thin like a plate
* Parallel surfaces
17
Q
Why are flat bones important?
A
• Protect underlying structures/ soft tissue
• serve as large surface area for tendon and ligament attachment
(Skeletal muscles)
18
Q
Where can you find flat bones
A
- Cranial Bones
- Sternum
- Ribs
- Scapula
19
Q
How are Long bones?
A
- longer than wide
- most common type of bone
- range from very large femur to small phalangeal bones
20
Q
What are some examples of long bones?
A
- arm and forearm
- leg and thigh (largest, heaviest)
- Palm
- soles
- fingers
- toes
21
Q
How are sesame if bones?
A
- small
* flat
22
Q
Where are sesame if bones found?
A
- Develop inside tendons
- near joints at hands, knee, feet
- ex: patellas
- other places may vary
- up to 26 locations
23
Q
What is another name for bone markings?
A
- surface features
* landmarks
24
Q
What are the 3 types of bone markings?
A
- Elevation or projections
- Depression or groove
- Tunnels
25
What happens at elevations and projections?
* Tendons and ligaments attach
| * Articulations with other bones
26
What happens at Depressions or groove?
• Something else fits along side the bone surface
27
What happens at the Tunnels?
• Blood and nerves enter bone
28
Landmark names for elevations and projections
1. Process
| 2. Ramus
29
What are processes?
• projection or bump
30
What is a ramus?
* extension of a bone
| * forms angle with the rest of the structure
31
Landmark names for openings
1. Sinus
2. Foramen
3. Fissure
4. Meatus
5. Canal
32
What is a sinus?
* chamber w-in a bone
| * normally filled with air
33
What is a foramen?
• rounded passageway for blood/ vessels and/or nerves
34
What is a fissure?
* deep furrow
* cleft
* slit
35
What is a meatus?
* passage or channel
| * opening of a canal
36
What is a canal?
* duct
| * channel
37
In what processes do ligaments and tendons attach?
1. Trochanter
2. Crest
3. Spine
4. Line
5. Tubercle
6. Tuberosity
38
WhT is a trochanter?
• large rough projection
39
What is the crest of a bone?
• prominent ridge
40
What is a spine?
• pointed process
41
What is the line?
• low ridge
42
What is a tubercle?
• small, rounded projection
43
What is a tuberosity?
• rough projection
44
Landmark names for depressions
1. Sulcus
| 2. Fossa
45
What is a sulcus m?
• narrow groove
46
What is a fossa?
• shallow depression
47
What processes form where joints (articulations) occur between adjacent bones?
1. Head
2. Neck
3. Facet
4. Condyle
5. Trochlea
48
What is the head?
• articulate end of epiphysis
49
What is the neck?
• narrow connection between epiphysis and diaphysis
50
What is the facet?
* small, flat
| * articular surface
51
What is Althea condyle?
• smooth, rounded articulate process
52
What is a trochlea?
* smooth, grooved articulates process
| * shaped mine a pulley
53
What are the 3 parts of a long bone?
1. Epiphysis
2. Diaphysis
3. Metaphysis
54
What is the epiphysis?
• the wife part at each end of a long bone
55
What happens at the epiphysis?
• articulation a with other bones
56
Describe the epiphysis
* mostly spongy (cancellous) bone
| * covered with compact bone (cortex)
57
What is the diaphysis?
• shaft of long bone
58
Describe the diaphysis
* heavy wall of compact bone
| * has a central space
59
What is the central space of the diaphysis called?
• medullary (marrow) cavity
60
What is the metaphysis?
• where the diaphysis and the epiphysis meet.
61
What does the structure of a flat bone resemble?
• a sandwich of spongy bone between 2 layers of compact bone
62
What is the compact part of a flat bone called?
• cortex
63
WhT is the spongy part of a flat bone called?
• diploë
64
What type of CT is bone (osseous) tissue?
• dense, supportive CT
65
What kind of cells does bone tissue contain?
• specialized cells
66
What does bone tissue produce?
• solid matrix
67
What is the solid matrix made out of?
• Calcium salt deposits that organized around collagen fibers
68
What are the characteristics of bone tissue?
* dense matrix
* osteocytes
* canaliculi
* periosteum
69
What does the dense matrix contain?
* Calcium salts
* fibrous protein
* osteocytes (bone cells) w/in lacunae
70
Where are osteocytes found?
• organized around blood vessels
71
What are canaliculi?
• pathways for access to blood vessels
72
What does canaliculi do?
• exchange nutrients and waste
73
What is periosteum?
• cover of outer surfaces
74
What does periosteum consists of?
* outer fibrous layer
| * inner cellular layer
75
What are the 2 components of bone matrix?
1. Minerals
| 2. Matrix Proteins
76
How much of bone matrix is composed of minerals?
• 2/3 calcium phosphate
77
What happens when calcium phosphate reacts wth other minerals?
• forms crystals of hydroxyapatite
78
How much of bone matrix is made of proteins?
• 1/3 collagen
79
How much of bone mass is made up of bone cells?
• 2%
80
How many types of cells does bone contain?
•4
1. Osteocytes
2. Osteoblasts
3. Osteogenic cells
4. Osteoclasts
81
What are osteocytes cells?
* mature bone cells
* maintain bone matrix
* do not divide
82
Where are osteocytes found??
• living in lacunae, between layers of lamellae
83
How are osteocytes connected through each other?
• through cytoplasmic extensions of canaliculi
84
Whats te the 2 major functions of osteocytes?
1. Maintain protein and mineral content of matrix that continually dissolve and rebuild matrix
2. Repair damage bone
85
What are osteoblasts?
* immature bone cells
| * osteogenesis
86
What does osteoblasts do?
* secrete matrix compound
| * builds
87
What is the matrix produced by osteoblasts called?
• osteoid
88
Why can osteoid form bone?
• not yet calcified
89
What happens when osteoblasts is surrounded by bone?
• it becomes osteocytes
90
Where is osteoblasts found??
• outer edge
91
What are osteogenic cells?
• Mesenchymal stem cells that divide to produce osteoblasts
92
What is another name for osteogenic cells?
• osteoprogenitor cells
93
Where are osteogenic cells located?
* endosteum that lines medullary cavity
| * inner cellular layer of periosteum
94
What does osteogenic cells assists with?
• fracture repair
95
What are osteoclasts?
• giant, multinucleate cells
96
What does osteoclasts secrete?
* acids and protein-digesting enzymes
| * to remove and recycle bone matrix
97
What is the process of dissolving bone matrix and release of stored minerals called?
• osteolysis (lysosomes)
| -----degradation
98
What maintains homeostasis of the bone?
* osteoblasts (builds)
| * osteoclasts (recycles)
99
What happens when more breakdown than building occurs?
• bones become weak
100
What type of exercise causes osteoblasts to build bone?
• weight bearing exercise
101
What is the beach unit of compact bone?
• osteon
102
Osteocytes are arranged in concentric lamellae around what type of canal?
• central canal containing blood vessels
103
What runs perpendicular to central canals?
• perpendicular canals
104
What do perpendicular canals do?
• carry blood vessels into bone and marrow
105
What is wrapped around the long bone?
• circumferential lamellae
106
What does circumferential lamellae do?
• binds osteons together
107
Instead of osteon, what does spongy bone have?
• open network or trabeculae
108
Does trabeculae contain blood vessels?
• false
109
With what is the space between trabeculae filled with?
• red bone marrow
110
What does ten bone marrow contain?
* blood vessels
* red blood cells
* nutrients for osteocytes
111
What other type of marrow can sometimes be found in spongy bone?
• yellow bone marrow
112
Why is yellow bone marrow it's color?
• contains fat cells
113
What is compact bone covered with?
• periosteum
114
The periosteum covers all bones; except?
• parts enclosed in joint capsules
115
Collagen fibers of the periosteum that connect with collagen fibers of bone are called?
• perforating fibers
116
What do perforating fibers also connect wth?
* fibers of joint capsules
* tendons
* ligaments
117
What are the 3 functions of the periosteum?
1. Isolate bone from surrounding tissue
2. Provides route for circulatory and nervous supply
3. Participates in bone growth and repair
118
What is compact bone covered by on the inside?
• endosteum
119
Around what age does human bone growth stops?
• 25
120
What is the formation of bone called?
• ossification
121
What is the process of depositing calcium salts into the bone during ossification called?
• calcification
122
What are the 2 mains forms of ossification?
1. Endochondral ossification
| 2. Intramembranous ossification
123
What is it called when a bone replaces existing cartilage?
• Endochrondral ossification
124
What is it called when a bone develops directly from connective tissue?
• Intramembranous ossification
125
Which of the process of bone making involves cellular differentiation?
• both
126
What is cellular differentiation?
• cells change their gene expression in response to signal molecules
127
In endochondral ossification; where do ossified bones originate from?
• hyaline cartilage
128
Where do most bones originate from?
• hyaline cartilage
129
How many steps is there in endochondral ossification?
•7
130
Where does those 7 steps occur?
• during fetal development
131
What happens during step1?
* cartilages enlarges
* chondrocyte swear center increases in size
* matrix reduces and begins to calcified
* enlarged chondrocytes die and disintegrate leaving cavities in cartilage
132
What happens in step2?
* blood vessels grown around the edges of the cartilage
* cells in the periosteum convert to osteoblasts
* shaft of cartilage becomes ensheathed
133
What happens in step3?
* blood vessels penetrate the cartilage, invade central region
* fibroblast differentiate into osteoblasts, producing spongy bone
* bone formations spreads along shaft
134
What happens in step 4?
* remodeling occurs as growth continues
* medullary cavity is created
* osseous tissue thickens
* cartilage near epiphysis is replaced by shafts of bone
135
What happens at step5?
* capillaries and osteoblasts migrate into epiphysis
| * creates secondary ossification center
136
What happens at step6?
* epiphysis becomes filled w/ spongy bone
* metaphysis (epiphyseal plate) is created
* on the shaft; osteoblasts invades cartilage and replaced it with bone
* new cartilage is produced at epiphyseal side
137
What happens at step6 at the epiphyseal region? ? Pt2
* In the epiphyseal cartilage chondrocyte organize into zones
* chondrocyte continue to divide/enlarge/degenerate
* osteoblasts migrates and replaces cartilage with bone
138
What happens at step7?
* at puberty; epiphyseal cartilage slows down
* rate of osteoblasts accelerates
* epiphyseal closure happens
* epiphyseal line is left behind
* thin cap of original cartilage remains for articulation
139
What is the epiphyseal closure?
• narrowing of the epiphyseal cartilage until it disappears
140
What is another name for intramembraneous ossification?
• dermal ossification
141
Why is it called dermal ossification?
•occurs at the dermis
142
What type of bone is created during intramembraneous ossification?
• dermal bones
143
What are some examples of dermal bones??
* mandible
| * clavicle
144
When does intramembraneous ossification begin?
• around 7th week of embryonic development
145
How many steps of intermembranous ossification is there?
•5
146
What happens in step1 if dermal ossification?
* mesenchymal cells group together and becomes osteoblasts
| * starts to secrete organic compounds of the matrix
147
What happens in step2 of dermal ossification?
* some osteoblasts get trapped inside bony pockets
* trapped osteoblasts become osteocytes
* developing bone fries outward in small struts called spicules
148
What happens in step3 of dermal ossification?
* blood vessels begin to branch out and grow between spicules
* rate of bone growth accelerates
* as spicules interconnect; they trap blood vessels w/in bone
149
What happens in step4 of dermal ossification?
• deposition of bone by osteoblasts located close to blood vessels result in PLATE of spongy bone
150
What happens in step5 of dermal ossification?
* Osteons are produced
| * osteoblasts become periosteum
151
How is blood supplied to mature bone?
1. Nutrient artery and vein
2. Metaphyseal vessels
3. Periosteal vessels
152
What happens at nutrient artery and vein?
* single pair of large blood vessels enter diaphysis through nutrient foramen
* femur has more than 1 pair
153
What does the metaphyseal vessels do?
• supply epiphyseal cartilage where bone growth occurs
154
What does the periosteal vessels do?
* supply blood to superficial patrons
| * secondary ossification centers
155
What happens to 1/5 of the human skeletal each year?
• it is recycled and replaced
156
What does this process of remodeling involve?
* osteocytes
* osteoclasts
* osteoclasts
157
What happens if deposit is greater than removal?
• bones get stronger
158
What happens if removal is greater than replacement?
• bones get weaker
159
How does mineral recycling affect bones?
• allows bones to adapt to stress
160
What happens to heavily stressed bones?
• become thicker and stronger
161
How much bone can degenerate after a few weeks of inactivity?
• 1/3
162
What are some source of. Untrue ts we must consume?
* calcium
* phosphate salts
* magnesium
* fluoride
* iron
* manganese
163
What hormone facilitates calcium and phosphorus absorption?
• calcitriol
164
What is required for synthesis of calcium and phosphate?
• vitamin D3
165
What are some important vitamins we need to consume?
• A, C, K and B12
166
What hormones stimulate bone growth?
* growth hormone
| * thyroxine
167
What is thyroxine?
• thyroid hormone
168
What stimulates osteoblasts?
* estrogen
| * androgen
169
What regulates calcium and phosphate levels?
* calcitonin
| * parathyroid hormone
170
Why is calcium important?
• for function of membranes, neurons and muscle cells
171
How much of the body is calcium and phosphate?
• 99%
172
How much of the body contains carbonate?
• 80%
173
How much of the body contains magnesium?
• 50%
174
How much of the body co rains sodium?
• 35%
175
How much of the. It's contains potassium?
• 4%
176
What maintains homeostasis of hormones and calcium?
* calcitonin
| * parathyroid hormone
177
Where is calcium stored?
• in bones
178
Where is calcium absorbed?
• in digestive Tract
179
Where is calcium excreted?
• kidneys
180
Where is parathyroid (PTH) hormone produced?
• parathyroid glands in neck
181
How does PTH increases calcium ion levels?
1. Stimulates osteoclasts
2. Increase interstitial absorption
3. Decrease calcium excretion
182
What secretes calcitonin and where?
* C cells
| * in thyroid
183
What is another name of C cells?
• parafollicular cells
184
How does calcitonin decrease calcium ion levels?
1. Inhibiting osteoclasts activity
2. Decrease interstitial absorption of calcium
3. Increases calcium excretion at kidneys
185
How many steps are needed to repair fractures?
• 4
186
What is step1 of fracture repair?
* blessing produces clot
| * establishes fibrous network
187
What is step2 of fracture repair?
* cells of endosteum and periosteum decide and move into fracture area
* form calluses of cartilage/bone to stabilize fracture
188
What is step3 of fracture repair?
* osteoblasts replace cartilage of callus with spongy bone
| * straits of spongy bone connect broken ends
189
What is step4 of fracture repair?
* osteoclasts and osteoclasts remodel bone for up to a year
| * when remodeling is complete, calluses dare gone and compact bone remains
190
What is inadequate ossification that occurs between ages 30 and 40?
• osteopenia
191
How much bone mass do women lose per decade?
• 8%
192
How much bone mass do men lose per decade?
• 3%
193
What are the bones most affected by age?
* epiphyses
* vertebrae
* jaws
194
What realists with bone mass reduction?
* fragile limbs
* height reduction.
* tooth loss
195
What is osteoporosis?
• severe bone loss
196
What is the percentage of woman and men that have osteoporosis?
* 29% of woman
* 18% of men
* over 45 yrs of age
197
When does bone loss in woman accelerate?
• after menopause
198
What helps maintain bone mass?
• estrogen and androgen
199
In cancer patients; what do cancerous tissue release?
• osteoclasts- activating factors
200
What does osteoclasts- activating factors stimulates?
• osteoclasts which produces severe osteoporosis
