Chapter 11.6 - Skeletal System Flashcards
(112 cards)
1
Q
Invertebrate skeletons belong to:
A
organisms without bones, especially backbones
2
Q
axial skeleton
A
skull, vertebral column, rib cage
3
Q
appendicular skeletons
A
bones in the appendages, pectoral and pelvic girdle
4
Q
what are the different types of bones in the endoskeletal system?
A
- flat bones
- short bones
- long bones
- sesamoid
- irregular
5
Q
Distinct features of long bones
A
Epiphyses The diaphysis A medullary cavity Metaphyses Epiphyseal plates
6
Q
Shaft of a long bone is called:
A
diaphysis
7
Q
Bumpy ends of long bones
A
epiphyses
8
Q
True or false: long bones have a hollow diaphysis
A
false - filled by medullary cavity containing spongy bone (yellow bone marrow)
9
Q
Outside of epiphyses have:
A
articular cartilage. covers compact bone to form synovial joints
10
Q
How many types of synovial joints are there?
A
6
11
Q
Name the types of synovial joints
A
- ball and socket
- hinge
- plane
- pivot
- condylar
- saddle
12
Q
Function of hyaline cartilage
A
cushions joints at the end of long bones, absorbs shock
13
Q
What structure connects adjacent Haversian systems to the periosteum?
A
Volkmann’s canals
14
Q
Which layer(s) of the periosteum contain(s) osteoprogenitor cells?
A
cambium layer
15
Q
When is the primary ossification center established?
A
when osteoblasts invade the calcified center of the cartilage model
16
Q
How does parathyroid hormone respond during times when blood calcium levels are low?
A
PTH increases calcium when it is low in the blood by stimulating osteoclasts
17
Q
What covers the outside portion of the diaphysis?
A
periosteum
18
Q
What term describes the canals that connect lacunae and Haversian canals of a single osteon?
A
canaliculi
19
Q
Diarthroses
A
synovial joints between bones that fully move
20
Q
Where can osteoclasts be found?
A
howship’s lacunae
21
Q
What is not a component of a synovial joint?
A
elastic cartilage
22
Q
Components of matrix of hyaline cartilage
A
elastin, chondroitin sulfate, collagen
23
Q
What type of cartilage is found in the intervertebral discs?
A
fibrous cartilage
24
Q
Where do bone cells that are supplied nutrients from Haversian canals reside?
A
lacunae
25
What are the components of the cartilaginous matrix secreted by chondroblasts?
collagen; elastin
26
Where is the Achilles tendon located?
back of lower leg
27
A basketball player suffers a severe tear in his Achilles tendon. Which of the following will occur at the site of injury?
tendon repair process involves the recruitment of inflammatory cells and fibroblasts from outside the tendon tissue to the injury site
28
Fibroblasts synthesize:
Extracellular matrix and collagen
29
___ play a critical role in adhesion formation and wound healing
fibroblasts
30
A tear in the Achilles tendon results in a weaker connection between:
muscle and bone (not between bone and bone - that's if a ligament is torn)
31
What layer covers the surface of cortical bone?
periosteum
32
If you look inside epiphyses, you would see:
spongy bone with red bone marrow
33
When do epiphyseal plates ossify?
when pubertal hormones signal for calcification and apoptosis
34
What direction do epiphyseal plates grow?
towards metaphyses
35
short bones are ____
cuboidal
36
Function of short bones
provide support with very little movement
37
Example of long bone
femur, radius, ulna
38
Example of short bones
bones in the wrist
39
Flat bones
cortical bone surrounding spongy bone in the middle
40
Example of flat bones
sternum, skull
41
Sesamoid bones are embedded within ____
tendons
42
Sesamoid bones function
increases muscle's leverage on the bone it is attaching to
43
Example of sesamoid bone
patella
44
Irregular bones composed of:
thin cortical layers surrounding abundant cancellous interiors
45
Example of irregular bone
pelvis and spine
46
What allows bones to support our weight?
the density of cortical bone
47
Microstructures in cortical bone:
```
Osteons
Haversian canals
Lamellae
Lacunae
Volkmann's canals
Canaliculi
```
48
___ are considered the functional unit of cortical bone
osteons
49
Describe structure of osteons
multi-layered cylinders that extend parallel to the bone's long axis
50
In the center of osteon is:
Haversian canal
51
Function of haversian canals
contains blood cessels to supply nutrients to various types of bone cells living in lacunae
52
Lacunae
small spaces between lamellae that house bone cells
53
True or false: lacunae are independent units
false - they connect to each other/haversian canal via canaliculi
54
Volkmann's canals function
connect adjacent haversian systems to the periosteum which supplies the bone with blood and nutrients
55
____ is the inner network of bones
cancellous bone (spongy bone)
56
True or false: cancellous bone contains osteons
false
57
Cancellous bone contains:
web of trabeculae that soap up bone marrow like a sponge
58
Osteoprogenitors
immature precursor cells that mature into osteoblasts
59
Osteoblasts have ___ nucleus/nuclei
1 (mononucleate)
60
Function of osteoblasts
- build bone
- secrete proteins and collagen that make osteoid
- make an enzyme to create hydroxyapatite
61
Osteoblasts mature into ____ once they:
osteocytes; once they secrete enough bone matrix that they are trapped by it
62
Osteocytes are:
highly branched cells that communicate with other cells to maintain bone
63
Where can you find osteocytes?
in lacunae
64
Osteoclasts have ___ nucleus/nuclei
many (multinucleated)
65
Osteoclasts are derived from:
monocytes
66
Function of osteoclasts
chew through bone (resorb bone)
67
Where are osteoclasts found?
Howship's lacunae
68
True or false: once made, bones cease to remodel and stay as is
False - bones undergo lifelong remodeling
69
Primary mechanisms that affect bone remodeling:
1. parathyroid hormone
2. Vitamin D (calcitriol)
3. Calcitonin
70
Which mechanisms decrease blood calcium levels?
calcitonin (tones down blood calcium)
71
Which mechanisms increase blood calcium levels?
1. parathyroid hormone
| 2. calcitriol (vitamin D)
72
Parathyroid hormone (PTH) is secreted by:
Parathyroid gland
73
PTH stimulates:
osteoclasts
74
Calcitonin is secreted by:
thyroid gland
75
Vitamin D function in blood calcium levels:
increases calcium reabsorption in the intestines, provides negative feedback to PTH secretion
76
Organic component of bone matrix:
osteoid
77
Osteoid contains:
type 1 collagen fibers and proteins
78
Function of osteoid
gives bones slight flexibility and tensile strength
79
Inorganic component of bone matrix:
hydroxyapatite
80
Hydroxyapatite is made of:
calcium, phosphate, water crystallized
81
Embryonic ossification types:
intramembranous and endochondral ossification
82
Steps of intramembranous ossification
1. osteoblasts secrete osteoid, creating osteocytes (ossification center forms in mesenchyme)
2. Osteocytes form trabeculae, gets wrapped by blood vessels creating periosteum
3. cortical bone begins to grow between periosteum and trabeculae
83
What bones are formed via intramembranous ossification
Flat bones
84
Endochondral ossification steps
1. cartilage model created at week 8
2. center of cartilage model starts to calcify
3. week 12 - osteoblasts and capillaries begin to invade calcified center -- creates primary ossification center
4. secondary ossification created at epiphyses, osteoclasts chew out inside of diaphysis
85
What bones are made via endochondral ossification
long bones
86
Fibrous connective tissues include:
tendons, ligaments, periosteum and endosteum
87
Tendons connect:
muscle to bone
88
Ligaments connect:
bone to other bones
89
What is the periosteum?
protective fibrous membrane that covers cortical bone (except at epiphyses where you find articular cartilage)
90
Periosteum has _ sub layers:
2; fibrous layer, inner cambium layer
91
True or false: fibrous layer of periosteum is highly innervated and vascularized
true
92
Cambium layer has ___ that allow for attachment of:
collagen fibers; periosteum to the cortical bone underneath
93
True or false: fibrous layer of periosteum contains osteoprogenitor cells
false - cambium layer contains osteoprogenitor cells
94
Endosteum
single layer membrane that lies between cortical and cancellous bone
95
Endosteum lines the:
- medullary cavity
- surrounding cancellous bone of epiphyses
- lining cavities of Haversian/volkmann's canals
96
Cartilage is not:
vascularized or innervated
97
Chondroblast
build cartilage
98
When do chondroblasts mature into chondrocytes?
When they become trapped by the matrix they create
99
Where are chondrocytes found?
cartilaginous lacunae
100
What do chondroblasts secrete?
collagen and elastin
101
Types of cartilage:
hyaline, fibrous, elastic
102
Hyaline cartilage made of:
chondroitin sulfate, collagen, elastin (glassy appearance)
103
Where is hyaline cartilage found?
between the ribs and sternum, in the nose, and the trachea
104
Fibrous cartilage function
provides rigidity and resists tension
105
Where is fibrous cartilage found?
intervertebral discs, knee meniscus
106
Elastic cartilage
similar to hyaline cartilage but has a lot more elastin proteins
107
Where is elastic cartilage found?
ears, epiglottis
108
Synarthroses
dense, fibrous joints between bones that do not move
109
Amphiarthroses
cartilaginous joints between bones that partially move
110
Diarthroses
synovial joints between bones that are fully movable
111
Which type of joint is unstable and accounts for many injuries?
Ball and socket
112
What do synovial joints contain?
Bones
Articular cartilage covering opposing epiphyses
Ligaments
Fibrous joint capsule
Synovial fluid lubricant within joint cavity
