Anatomy Ch 7- Musculoskeletal system Flashcards
(102 cards)
1
Q
What are the 5 functions of the bone?
A
Support, protection, movement, mineral storage, blood cell formation
2
Q
How does bone protect?
A
The fused bones of the skull protect the brain
- the vertebrae surround the spinal cord, and the rib cage helps protect the vital organs of the thorax
3
Q
How does bone provide movement?
A
Skeletal muscles use bones as levers
4
Q
Mineral storage
A
calcium and phosphate
5
Q
blood cell formation
A
hematopoiesis- RBW and WBC forms within red marrow cavities of certain bones
6
Q
what is compact bone
A
- Dense or cortical bone
- 80% of bone mass
7
Q
what is spongy bone?
A
-Cancellous or trabecular bone
- Located internally to compact bone
- Appears porous
- 20% of bone mass
8
Q
What is cartilage?
A
Semirigid Connective tissue; more flexible than bone
9
Q
What is fibrocartilage?
A
- Weight-bearing cartilage that withstands compression
- Located in intervertebral discs, pubic symphysis, menisci of the knee
10
Q
What is hyaline cartilage?
A
- model for bone formation
- Found in ribs, ends of bones
- Attaches ribs to the sternum, covers ends of some bones within growth plate
11
Q
Name two structures composed of dense regular connective tissue..
A
Ligaments: connect bone to bone
Tendons: connect muscle to bone
12
Q
What is the major structural and supportive connective tissue in the body?
A
Osseous tissue or (bone tissue)
13
Q
Name this tissue: soft fatty tissue found in cavities of bones
contains red bone marrow and yellow bone marrow
Red marrow: site of blood cell production
Yellow marrow: fat storage
A
Marrow tissue
14
Q
Define Red bone marrow
A
- hemopoietic (blood cell forming)
- reticular CT, immature blood cells, and fat
15
Q
Where is red bone marrow located in children?
A
Located in spongy bone and medullary cavity of long bones
16
Q
Red bone marrow in adults is located where?
A
- located only in selected areas of the axial skeleton
- such as the skull, vertebrae, ribs, sternum, ossa coxae, proximal epiphyes of humerus and femur
17
Q
What is yellow bone marrow?
A
- product of red bone marrow
- degeneration as children mature
- fatty substance
- may convert back to red bone marrow
18
Q
What are the 5 shape classifications of bone ?
A
- Long bone
- short bone
- flat bone
- irregular bones
- sesamoid bones
19
Q
Long bones are ?
A
bones that are longer than they are wide
20
Q
Short bones are ?
A
bones that are equally long and wide
21
Q
Irregular bones are ?
A
bones that do not fit into any category
22
Q
Sesamoid bones are ?
A
- bones that are small, flat, and oval-shaped
- specialized bones found within tendons
23
Q
flat bones are ?
A
- bones that are thin, broad, and commonly curved; sutural bones can be grouped here
24
Q
What is periosteum?
A
- outer layer covering bone
- fibrous layer and cellular layer
25
What are perforating fibers?
collagen fibers; anchors attaches periosteum to bone
26
compact bone is ?
Hard, dense bone tissue
27
Spongy bone
Layer of bone tissue having many small spaces and found just inside the layer of compact bone
- called cancellous , "trabecular"
28
Epiphysis
End of a long bone
29
Diaphysis
shaft of a long bone
30
Epiphyseal lines
remnants of a growth plate
31
Endosteum
Lines the inner surface of bone tissue (inside)
32
Nutrient artery
large artery that enters compact bone near the middle of the diaphysis
33
Medullary cavity
cavity within the shaft of the long bones filled w/ bone marrow
34
Outer fibrous layer of periosteum is made of ? Does what?
- dense irregular CT
- protects bone from surrounding structures
- anchors blood vessels and nerves to bone surface
- attachment site for ligaments and tendons
35
inner cellular layer of periosteum includes what
includes osteoprogenitor cells, osteoblasts, and osteoclasts
36
Describe blood supply of bone
- bones are highly vascularized in regions of spongy bone
- vessels enter from periosteum
37
Nutrient foramen is a ?
small opening or hole in a bone for nutrients to come into
- artery entrance and vein exit here
38
Nerves that supply bone
- accompany blood vessels through foramen
- innervate bone, periosteum, endosteum, and marrow cavity
- mainly sensory nerves
39
Osteons
- cylindrical structures that comprise compact bone
40
Central canal
contains blood vessels and nerves
41
Osteons connect to each other via
perforating canal
42
canaliculi
connect adjacent lacunae containing osteocytes and secretions
- serve as a channel allow exchange of nutrients, minerals, gases, and wastes between blood vessels and osteocytes
- house osteocyte cytoplasmic projections that allow intercellular contact and communication
43
Osteoprogenitor cells
- stem cells
- cellular division yields another stem cell and a "committed cell" > asymmetric division
- becomes OSTEOBLAST & REPLACES old/injured bone cells
44
osteoprogenitor cells are located in ___ and ____. They release what?
Located in Periosteum and endosteum
release calcium
45
What are osteoblasts?
they are building bone that secrete OSTEOIDS and then bone tissue differentiates into OSTEOCYTES
46
What are the two different types of bone?
spongy and compact
47
What is an osteoid?
The initial semisolid organic form of bone matrix/tissue
- contains collagen
- becomes calcified
- contributes to bone flexibility
- becomes entrapped within the matrix/tissue
48
What are osteocytes?
Mature bone cells that lack bone-forming abilities
- maintain bone tissue
- detects stress on bone that triggers OSTEOBLASTS to form new bone
49
The hormone that is produced in the thyroid gland and has the greatest effect on children's blood calcium levels is ____
CALCITONIN
50
What are osteoclasts? Their function?
- Large, multinuclear, phagocytic cells
- Derived from fused bone marrow cells
- Display a ruffled border > increases surface area exposed to bone
- involved in bone resorption > broken down
51
What is howships lacunae?
- Location of osteoclasts
- small depressions on bone surface
52
Over activity of osteoclasts would have which of the following effects?
Bone loss, possibily leading to osteoporosis
53
Bone formation process
- begins with secretion of osteoid
- calcification/mineralization occurs, deposition of hydroxyapatite crystals
- calcium and phosphate ions precipitate out and form crystals
54
What is required for bone formation to occur?
- Vitamin D: enhances calcium absorption from GI tract
Vitamin C: required for collagen formation
Calcium and phosphate: for calcification
55
When does ossification begin ? How long does it continue?
- Begins in the embryo, by 8-12 weeks of embryonic development
- continues through childhood and adolescence
56
What are the two processes that causes bone to ossify?
Intramembranous ossification
Endochondral ossification
57
Define Intramembranous ossification
- makes the minority of our body
- bone cells come from mesenchyme (stem) cells; making many bones of the skull and PART of the CLAVICLE
58
Define endochondral ossification
- makes the majority of our body
- bone cells deposited in hyaline cartilage
- Chondrocytes die and the area is calcified; producing MOST bones of the SKELETON
59
Define Appositional growth and what is it?
- increases bone thickness
- osteoblasts differentiate into osteoclasts, which break down bone on the INNER surface to PREVENT the bones from becoming TOO heavy
60
What is Bone resorption and what's the importance of it?
- Bone matrix is destroyed by substances releases from osteoclasts
- Proteolytic enzymes are released from lysosomes within osteoclasts
- chemically digest organic matrix components
- calcium and phosphate DISSOLVED by HYDROCHLORIC ACID
- freed calcium and phosphate ions ENTER the BLOOD
- Bone resorption important because occurs when BLOOD CALCIUM levels are LOW
61
What gland produces your growth hormones??
Anterior Pituitary Gland
62
Growth hormone stimulates the liver to produce ?
Insulin-like growth factors (somatomedins)
63
What hormones stunt growth ?
Glucocorticoids and Serotonin
64
Where are Glucocorticoids released from? What do they do?
- Released from the adrenal cortex
- regulated blood glucos level
65
High amounts of glucocorticoids increases _____
Bone loss.
- impairs growth at epiphyseal plate in children
- must monitor children w/asthma
66
What is serotonin?
-Neurotransmitter and hormone
- MOST bones w/ serotonin receptors
67
If serotonin levels are too high
- osteoprogenitor cells are prevented from differentiating into osteoblasts
- could be linked to low bone density disorders
68
High plasma calcium levels associated with which gland?
- triggers the release of CALCITONIN from the THYROID gland
- calcium salts deposited in the bone
69
Calcitonin duty?
- removes calcium from the blood and puts it into bone
- increases activity of osteoblasts
70
Low plasma calcium levels associated w/which gland?
- Triggers the release of parathyroid hormone (PTH) from the parathyroid glands
- PTH will stimulate OSTEOCLAST activity .... releasing calcium FROM THE BONE .... and resorbed by the kidneys and intestines
71
Parathyroid hormone does what?
breaks down calcium from bone and puts it into the blood
- stimulates osteoclasts activity
72
Transverse fracture
occurs straight across the bone
73
stress fracture
Thin break caused by increased physical activity (crack not fully broken)
74
Oblique fracture
occurs at an angle across the bone
75
Greenstick
- the bending and incomplete of a bone; most often seen in children
76
Comminuted Fracture
- bone breaks into many fragments
77
Pathologic fracture
fracture caused by diseased or weakened bone
78
Simple fracture
broken bone not penetrating the skin
79
compound fracture
bone breaks through the skin/ penetrates through the skin
80
How long does a simple fracture take to heal? How about compound?
2-3 months
Longer than 3 months
81
Four steps of healing a fracture
1- fracture hematoma forms
2- fibrocartilaginous (soft) callus forms
3- a hard (bony) callus forms
4- the bone is remodeled
82
Step 2: Fibrocartilaginous callus formation
- fracture hematoma reorganized into a CT procallus
- Fibroblasts produce collagen fibers
- procallus becomes fibrocartilaginous (soft ) callus
83
Step 3: hard (bony) callus formation
- Osteoblasts adjacent to the callus produce trabeculate
- replace soft callus
- forms a hard (bony) callus
- continues to grow and thicken
84
Step 4: Bone is remodeled
- final phase of fracture repair
- osteoclasts remove excess bony material
- compact bone replaces primary bone
- usually leaves a slight thickening of bone
85
causes of osteoporosis.
- Osteoclast activity outpacing osteoblast activity
- associated with loss of estrogen
86
Symptoms of osteoporosis? Diagnosis? Treatment?
- stooped posture; increased susceptibility to fractures
- measurement of bone density
- administration of estrogen or calcitonin; balanced diet; active lifestyle
87
OSTEITISDEFORMANS
- overactivity of osteoblasts AND osteoclasts
- excessive bone resorption followed by excessive bone deposition
- newly deposited bone is poorly formed
- genetic
88
Rickets
- disease caused by vitamin D deficiency in childhood
- characterized by deficient calcification of osteoid tissue
- bowlegged appearance
- disturbances in growth, hypocalcemia, and tetany (cramps and twitches)
- occurs in some developing nations
- incidence increasing in urban U.S. children
89
ACHONDROPLASIA
- form of short-limbed dwarfism
-means "without cartilage formation"
- deficiency in converting cartilage into bone
- autosomal dominant pattern
90
Cause of achondroplasia?
- mutations in the FGFR3 gene; Gene proides instruction for synthesizing a protein involved in the development and maintenance of bone
- failure of chondrocytes in epiphyseal plate to grow and enlarge
91
Acromegaly
- excessive growth AFTER fusion
- bones grow wide rather than longer
- tumor forms AFTER plates fuse
92
Gigantism
- excessive growth PRIOR to the fusion of the epiphyseal growth plates
- tumor on the pituitary gland as a child
93
***Bones are the site of blood cell production, known as ___
red bone marrow/ hematopoiesis
94
***How does the red bone marrow differ from yellow bone marrow?
red bone marrow produces blood cells.
yellow stores fat
95
***Where can you find red bone marrow in adult skeletons?
The axial skeleton; proximal ends of femur and humerus
96
***Where is the epiphysis of a long bone?
The ends; head and bottom
97
***Bone stem cells are ____
Osteoprogenitor cells
98
***What shape classification is the sphenoid bone?
irregular
99
***If blood calcium is too high, what hormone is released?
CALCITONIN
100
***What bone fracture is commonly caused by physical activity?
Stress fracture
101
***What type of bone growth makes bone thicker?
Appositonal growth
102
***What is the difference between acromegaly and gigantism?
Acromegaly is excessive growth AFTER fusion of epiphyseal growth plates.
Gigantism is growth PRIOR to the fusion of epiphyseal growth plates
