Bones Flashcards
1
Q
What are the functions of the skeletal system?
A
Support (Weight, teeth, organs) Protection (Skull, Ribs, Vertebrae) Movement Reservoir (Calcium, Phopsphorus) Hematopoiesis
2
Q
How many bones are in the body?
A
206
3
Q
What bones compose the axial skeleton?
The rest of the bones are a part of the ____________ skeleton?
A
Skull, Vertebrae, Ribs
Appendicular
4
Q
Bones of which TWO girdles attach the appendicular skeleton to the axial skeleton?
A
Pectoral
Pelvic
5
Q
What are the FOUR types of bones?
A
Long
Short
Flat
Irregular
6
Q
All limb bones are considered long bones except which bones?
A
- Patella
- Wrist Bones
- Ankle Bones
7
Q
T/F: Finger bones are considered short bones
A
False
They are considered long bones
8
Q
Bones of the hand/wrist and foot/ankle are considered _____ bones
A
Short Bones
9
Q
The scapula, sternum, ribs, and most skull bones are considered ________ bones
A
Flat
10
Q
Bones that have abnormal shapes and do not fit into the classification of either long, short, or flat would be considered what?
What are some examples of these?
A
Irregular bone
Scapula Vertebrae Hip Bones Sphenoid Ethmoid
11
Q
The outer layer of bone is ________ (dense/spongy) and is referred to as ________ (compact/non-compact) bone
A
Outer layer…….
Dense
Compact bone
12
Q
The inner layer of bone is ________ (dense/spongy) and has needle like projections called ________.
A
Inner Layer…..
Spongy
Trabeculae
13
Q
What are the bone building cells?
A
Osteoblasts
14
Q
T/F: Osteoblasts synthesize and secrete collagen
A
True
15
Q
What cells are responsible for maintaining bone tissue?
HINT: These are also referred to as mature bone cells
A
Osteocytes
16
Q
Osteocytes become trapped within the bone _____ in which they were secreted
A
Matrix
17
Q
What HUGE cells of the bone are responsible for the digestion of the matrix (bone resorption)?
A
Osteoclasts
18
Q
Where are osteoclasts primarily concentrated?
A
Endosteum
19
Q
Osteoclasts are created through fusion of 50 or more ________.
A
Monocytes
20
Q
Osteoclasts pump out ______ ions to create an _______ environment to eat away at the matrix
A
H+ Ions
Acidic
21
Q
What mechanism do osteoclasts use to create the acidic environment?
A
Proton Pump:
Breaks down H2CO3- into H+ and HCO3-
Exports H+ with Cl-
22
Q
What advantage does having a ruffled plasma membrane offer?
A
Increased Surface Area
23
Q
Why is it important to have osteoclasts ‘eating’ away at the bone?
A
To allow for remodeling
24
Q
Why are depressions often seen in the bone underneath an osteoclast?
A
Due to the acidic environment (H+ ions) eating away at the bone
25
1/3rd of the bone is made up of ________ (organic/inorganic) components while 2/3rds of the bone is made up of _________ (organic/inorganic) components
Organic
Inorganic
26
The organic material of bones consists primarily of _________ which is secreted by (osteoblasts/osteocytes/osteoclasts)
Proteins
Secreted by Osteoblasts
27
What is the 'main protein' in the organic material of bone?
What is this responsible for?
Collagen
Provides Resilience and ability to stretch
Resist over-stretching and twisting
28
What TWO salts compose the inorganic material in bones?
When these two salts interact, what do they form?
Calcium Phosphate
Calcium Hydroxide
Hydroxyapatite
29
Other than the calcium salts, what THREE 'minerals' can be found in the inorganic portion of bones?
Magnesium
Fluoride
Sodium
30
The inorganic components of bone allow for resistance to what?
Compression
31
The _________ of the bone consists of a thick collar of compact bone surrounding a central marrow cavity
Diaphysis
32
What collar is bone marrow in long bone in CHILD?
What color in ADULTS?
Children: Red
Adults: Yellow, Fatty
33
What is another name for the end of long bones?
Epiphyses
34
In the epiphyses, ________ (compact/spongy) bone covers _________ (compact/spongy) bone
Compact Bone covers Spongy Bone
35
Epiphyses are covered by ________ cartilage to reduce friction during movement
Articular Cartilage
36
What is the name of the double-layered membrane covering the external surface of a bone?
Does this cover joint surfaces?
Periosteum
No, the peristeum does not cover joint surfaces
37
What connects the periosteum to the bone matrix?
Collagen
38
T/F: The periosteum is POORLY supplied by nerve fibers, lymphatics, and blood vessels
False
It is richly supplied by those
39
Through what foramen do blood vessels enter the bone shaft?
Nutrient Foramen
40
What is the name of the delicate connective tissue that covers the internal surface of bones?
Endosteum
41
T/F: The endosteum covers the trabeculae of spongy bone in the marrow cavities
True
42
Endosteum contains both ________ and _________.
Osteoblasts
Osteoclasts
43
Do short, flat, and irregular bones have a diaphysis or epihysis?
No
44
Where do short, flat, and irregular bones contain bone marrow?
Trabeculae
45
In flat bones, what is the name of the internal spongy bone?
Diploe
46
Bone marrow occupies which cavity in long bones?
Medullary Cavity
47
T/F: Bone marrow exists in the larger haversian canal
True
48
What are the TWO main types of bone marrow?
Red
| Yellow
49
Red bone marrow is also considered ________ tissue
Hematopietic Tissue
50
Does bone marrow contain mature or immature RBCs?
Can bone marrow contain adipocytes?
Immature
Yes, scattered amounts
51
T/F: Yellow bone is considered hematopietically active
False
It is hematopietically INACTIVE
52
Under what circumstance could yellow bone marrow return to red marrow?
Anemia (Severe, Chronic)
53
Where does red marrow exist in adults?
Pectoral Girdle
Pelvic Girdle
Head of the Femur
Head of the Humerus
54
Compact bones contain what cylindrical structures which act as weight bearing pillars and are arranged parallel to one another?
Osteons (Harversian Systems)
55
In a Osteons (Harversian System), what is the name of the central canal that is surrounded by bone matrix?
What are FOUR things that pass through the above canal?
Haversian Canal
Arteries
Veins
Lymphatics
Nerves
56
What is the name of the concentric 'tubes' that surround the haversian canals?
Lamellae
57
Collagen fibers in neighboring lamellae run in ________ (The same/Opposite) directions, helping bone to better withstand twisting forces.
Opposite
58
What is the name of the canals that run perpendicular to the Haversian canals?
What are these responsible for?
Volkman's Canal
They bring blood and nerve supply from the periosteum to the haversian canals and to the medullary cavity
59
What is the name of the space that lies between intact osteons?
Interstitial Lamellae (Incomplete lamallae)
60
Osteocytes occupy small cavities known as ________?
Lacunae
61
What connects one lacunae to another one?
What type of 'junctions' allow for the exchange of nutrients, wastes, and chemical signals?
Canaliculi
Gap junctions
62
Does spongy bone contain a haversian system?
No
63
How does spongy bone get its blood supply if.....
the bone marrow is red?
the bone marrow is yellow?
Red: From the Marrow
Yellow: From Volkman's Channels
64
Prior to week 8, human embryonic skeleton ______ (fibrous/bony) membranes and cartilage
Fibrous
65
After week 8, the fibrous membranes and cartilage of the embyronic skeleton begin to be replaced by what?
Bone
66
____________ (Intramembranous/Endochondral) ossification involves the development of bone from fibrous membranes
Intramembranous Ossification
67
____________ (Intramembranous/Endochondral) ossification involves the replacement of hyaline cartilage with bone
Endochondral Ossification
68
What bones undergo intramembranous ossification ?
Prior to undergoing this what are these called?
```
Skull Cap
Facial Bones
Clavicles
Pelvis
Scapulae
Mandible
```
These are called Mesenchyme
69
What are the FOUR steps of intramembranous ossification?
1. Create an Ossification center
2. Create a bone maintenance mechanism
3. Vascularization
4. Maturation
70
What is Step 1 of intramembranous ossification?
Mesenchymal Cells cluster together and secrete organic material for the bone matrix which become mineralized through the crystallations of calcium salts
Mesenchymal cells eventually differentiate into osteoblasts
71
What is Step 2 of intramembranous ossification?
Osteoblasts differentiate into osteocytes
72
What is Step 3 of intramembranous ossification?
Bone grows outward from the ossification center in SPICULES
Blood vessels branch from the spicules
73
During what step of ossification does the periosteum form?
Step 3
74
T/F: Compact bone forms around the spicules in step 4 of ossification
True
75
During Step 4 of ossification what populates the spongy bone?
Red Bone Marrow
76
Most bones in the body develop via the __________ (intramembranous/endochondral) ossification model
Endochondral
77
How does endochondral ossification work?
1. Large chondrocytes grow creating large spaces in the center of bones, when they dies large spaces remain
2. Blood vessels fill those spaces brings in osteoblasts creating ossification centers
3. Compact bone then forms around these centers to form the shaft of bones
4. Bone replaces cartilage to form the epiphysis
5. Secondary ossification centers are created in the epiphysis, and a cartilaginous area remains to become the epiphyseal growth plate
78
T/F: Growth plates exist at primary ossification sites
False
Growth Plates exist at secondary ossification centers
79
Epiphyseal cartilage (close to the epiphysis) of the epiphyseal plate _________ (Divides/Transforms) to create more ________(cartilage/bone)
While the diaphyseal cartilage (close to the diaphysis) of the epiphyseal plate is __________ (Divided/Transformed) into _________ (bone/Cartilage).
This __________ (increases/decreases) the length of the shaft.
Divides
Cartilage
Transformed
Bone
Increases
80
Osteoblasts beneath the periosteum excrete bone matrix on the __________ (internal/external) surface of the bone making it thicker
Osteoclasts in the endosteum break bone on the ________ (internal/external) surface to widen the medullary cavity
What does this process result in?
External
Internal
This results in a increase shaft diameter without changing the relative amount of bone
81
During puberty osteoblasts begin producing bone _______ (faster/slower) than the rate of epiphyseal expansion
Faster
This happens until the growth plate gets narrower and narrower until it finally closes
82
What is precocious puberty?
What is this a risk factor for?
This occurs when the body goes into puberty to soon and can result in a shorter stature
83
Proper healing of a fracture depends on what?
Blood Supply
| Cellular Components of the bone
84
A fracture is considered ______ when both ends penetrate the skin
Open
85
A fracture is considered ________ when there are 3 or more bone fragments
Is this more common in children or the elderly?
Comminuted
Elderly
86
What type of fracture is more common in children and is described as a bone bending but not completely breaking?
Greenstick Fracture
Bone in children has more collagen and is less mineralized
87
A fracture is considered ________ one one bone fragment is driven into the medullary space or spongy area of another bone
Impacted
88
In regards to bone healing after a fracture......
Immediately after a fracture extensive bleeding occurs, which will ultimately result in a _________.
What happens as a result of this?
Hematoma
Bone cells are deprived of nutrient and die resulting in pain, swelling, and inflammation
89
In regards to bone healing after a fracture......
The hematoma will then be infiltrated by capillaries and _______ which gradually clean up debris to form _________ _______
Macrophages
Granulation Tissue
90
In regards to bone healing after a fracture......
Once granulation tissue forms, fibroblasts will produce ________ to span across the break, which will differentiate into ________ and begin making the cartilage matrix
Collagen
Chondroblasts
91
In regards to bone healing after a fracture......
Within the granulation tissue, osteoblasts will begin forming what?
Spongy Bone
92
In regards to bone healing after a fracture......
The entire structure of granulation tissue, chondroblast, and osteoblasts is referred to as what?
Fibrocartilagenous Callus
93
In regards to bone healing after a fracture......
Over 6-8 weeks following a fracture, the number of _________ increase converting the callus into a ______ callus
Trabeculae
Bony
94
In regards to bone healing after a fracture......
In the late stages, ________ will dismantle the temporary structures while ________ will rebuild the compact bone
Osteoclasts
Osteoblasts
95
What is the most common fracture that results in avascular necrosis of the hip?
What artery is interrupted in this case?
Femoral Neck Fx
Medial Femoral Circumflex Artery
96
What fracture in the hand can commonly be complicated by AVN?
Which artery is involved in the case?
PROXIMAL Scaphoid Bone
Radial Artery
97
In what "anatomical" location can the scaphoid be palpated?
Anatomical Snuffbox
98
AVN of the scaphoid results in survival of the _______ (proximal/distal) portion of the scaphoid) and death of the ___________ (proximal/Distal) portion of the scaphoid
Distal (Survives)
Proximal (Dies)
99
What is Wolff's Law?
Bone will grow or remodel in response to the forces or demands placed upon it.
100
Why might you suspect someone whose been a powerlifter for 15 years to have heavy, massive bones, especially at the point of muscle insertion?
Remember Wolff's Law
Bone will continue to remodel in response to the force and demand placed on it
So in this case, bone will increase in size to meet the demands placed on it
101
Astronauts tend to experience bone atrophy after they’re in space for an extended period of time. Why?
Remember Wolff's Law
Bone will continue to remodel in response to the force and demand placed on it
So in this case, the bone will shrink because there is not a lot of force acting on it
102
T/F: Normal bone growth/maintenance can occur w/o sufficient dietary intake of calcium and phosphate salts.
False
It will NOT occur
103
Calcium and Phosphate are absorbed in the intestines through what hormone?
What vitamin is this hormone made from?
Calcitrol
Vitamin D
104
Other than Vitamin D......
What vitamins are essential in bone growth?
Vitamin C, A, K, B12
105
Growth hormone and thyroxine ____________ (Stimulate/Halt) bone growth
Stimulate
106
How does GH influence bone growth?
Thyroxine?
GH Stimulates Protein synthesis and cell growth
Thyroxine stimulate metabolism and osteoblast activity
107
Which hormone (estrogens or androgens) causes the faster closure of growth plates
Estrogens
108
Is precocious puberty more common in men or women?
Women
109
Insulin stimulates bone ________ (formation/degradation)
Glucocorticoids stimulate ___________ (osteoblasts/osteoclasts)
Formation
Osteoclasts
110
Which TWO hormones antagonistically work to maintain Ca2+ levels in the blood?
Which one increases Ca2+ levels?
Decreases?
PTH (Increases Ca2+ levels)
Calcitonin (Decreases Ca2+ levels)
111
Calcitonin is released by which cells in the thyroid?
C-Cells
112
Calcitonin __________ (decreases/stimulates) osteoclast activity.
Calcitonin __________ (decreases/stimulates) osteoblast activity.
Decreases Osteoclast Activity (less bone breakdown = less Ca2+ in the blood)
Increases Osteoblast Activity (More Ca2+ from blood into bone matrix)
113
PTH binds to __________ (Osteoblast/Osteoclasts)
What occurs because of this?
Osteoblasts
Decreases osteoblast activity
Osteoblsts will then release osteoclast stimulating factor increasing osteoclast activity
114
PTH increases Ca2+ absorption by __________ (increasing/decreasing) calcitrol synthesis
Increasing
115
PTH _________ (increases/decreases) Ca2+ excretion in the urine and ___________ (increases/decreases) phosphate excretion in the urine
Decreases Ca2+ Excretion
Increases Phosphate Excretion
116
Osteomalacia is often referred to as "soft bones".
What are common causes of this?
Insufficient Ca2+ in the diet
Insufficient Vitamin D
Insufficient exposure to sunlight
117
What is the children's form of osteomalacia referred to as?
What bones is this commonly seen in?
Rickett's
Legs (Bowed)
Pelvis
Ribs
Skull
118
___________ is described as inflammation of the bone and bone marrow by pus-forming bacteria that enter the body typically via a wound.
Osteomyelitis
119
___________ is described as a group of diseases in which bone resorption occurs faster than deposition.
Bone becomes extremely porous?
Osteoporosis
120
What types of fractures are common in patients with osteoporosis?
Compression
Colles
Femur Fractures
121
When are women more likely to develop osteoporosis?
Post-Menopausal
Remember that estrogen stimulates osteoblasts and inhibits osteoclasts
