A+P Lecture 1 Flashcards
(121 cards)
1
Q
Describe axial skeleton
A
- Long axis of the body
- Skull, vertebral column, rib cage
- surrounds our CNS
2
Q
Describe long bones
A
- Longer than they are wide
- Limb bones
- where we house a lot of our bone marrow
3
Q
Describe appendicular skeleton
A
- Bones of upper & lower limbs
- Girdles attaching limbs to the axial skeleton
- think appendices
4
Q
Functions of the Msk system
A
- Support: for body & soft organs
- Protection: brain, spinal cord & vital organs
- Movement: levers for muscle action
- Mineral & growth factor storage: Ca++ & phosphorus, & growth factors reservoir
- Blood cell formation(bone marrow)
- Hematopoiesis occurs in red marrow cavities of certain bones
- Triglyceride (fat) storage and use as an energy source
- Hormone production
- Osteocalcin secreted by bones helps to regulate insulin secretion, glucose levels, & metabolism
5
Q
Describe flat bones
A
- Thin, flat, slightly curved
- Sternum, scapulae, ribs, most skull bones
6
Q
Describe short bones
A
- Cube-shaped bones (inwrist & ankle)
Sesamoidbones formw/n tendons (ex:patella) - Vary in size & # indifferent individuals
7
Q
Describe irregular bones
A
- Complicated shapes
- Vertebrae & hip bones
- think of spine
8
Q
Describe compact bone
A
dense outer layer on every bone that appears smooth & solid
9
Q
Describe spongy bone
A
made up of a honeycomb of small, needle-like or flat pieces of bone called trabeculae
10
Q
Why is the dispersal of bone marrow throughout bone important?
A
there’s no clear dispersal therefore bone marrow can be missed during biopsy
11
Q
What is found in the trabeculae of bone?
A
bone marrow
12
Q
Open spaces between trabeculae are filled with…
A
red or yellow bone marrow
13
Q
Describe structure of short, irregular & flat bones.
A
- Consist of thin plates of spongy bone (diploe) covered by compact bone
- Compact bone sandwiched b/t CT membranes
14
Q
What does periosteum cover?
A
covers outside of compact bone
15
Q
What does endosteum cover?
A
covers inside portion of compact bone
or covers the trabeculae of spongy bone
16
Q
What does hyaline cartilage do?
A
covers area of bone that is part of a movable joint
17
Q
What anchors directly to the periosteum?
A
tendons
18
Q
Describe structure of typical long bone.
A
All long bones have a shaft (diaphysis), bone ends (epiphyses) & membranes
19
Q
Define diaphysis.
A
- tubular shaft
- long axis of bone
- consists of compact bone surrounding central medullary cavity that is filled w/ yellow marrow in adults
20
Q
Define Epiphyses
A
ends of long bones that consist of compact bone externally & spongy bone internally
21
Q
What sits b/t the diaphysis & epiphysis?
A
epiphyseal line
22
Q
What is the epiphyseal line?
A
remnant of childhood epiphyseal plate (metaphysis) where bone growth occurs
–> growth plate
23
Q
Describe structure of the periosteum.
A
white, double-layered membrane that covers external surfaces except joints & is an anchoring point for tendons & ligaments
24
Q
What does the periosteum contain?
A
many nerve fibers & BVs that continue on to the shaft through nutrient foramen openings
25
What are the two layers of the periosteum & describe?
- Fibrous layer: secure to bone matrix
- Osteogenic layer: gives rise to most all bone cells
26
Describe structure of the endosteum.
Delicate CT membrane covering internal bone surface
27
Like periosteum, the endosteum contains
osteogenic cells that can differentiate into other bone cells
28
Osteogenic cells
Precursor stem cells to osteoblasts or bone-lining cells
29
Osteoblasts
Bone-forming cells
(osteoBlasts Build Bone)
30
Osteocytes
Mature bone cells & stimulate bone remodeling
31
Bone-lining cells
Flat cells on the surface of bone to help maintain bony matrix
32
Osteoclasts
Bone-breakdown
(osteoClasts Chomp bone)
33
Notes
Osteoclast are activated in some cancers causing the breakdown of bone
34
When are osteoclast activated
when serum Ca++ levels are low
--> they breakdown bone & bone releases Ca++ & other minerals
35
Define Ossification (osteogenesis)
- the process of bone tissue formation (a change from cartilage to bone)
36
When does the formation of bony skeleton begin?
month 2 in utero
37
When does postnatal bone growth occur until?
early adulthood
38
What two mechanism of bone are lifelong?
- bone remodeling
- bone repair
39
Up to about week 8, ___ and ___ of fetal skeleton are replaced with bone tissue
- fibrous membranes
- hyaline cartilage
40
Define Endochondral (cartilage) ossification
Bone forms by replacing hyaline cartilage to create most of skeleton
41
Define Intramembranous ossification
- Bone develops from fibrous membrane
- Bones are called **membrane bones**
42
Long bones grow lengthwise by ___ of epiphyseal plate
interstitial (longitudinal) growth
43
By the end of adolescence, what happens to the epiphyseal plate
- thins
- is replaced by bone
44
Epiphyseal plate closure occurs when the...
epiphysis & diaphysis fuse
45
When does bone lengthening stop in females?
around 18yo
46
When does bone lengthening stop in males?
around 21yo
47
Why is a break at the growth plate so important in pediatric pts?
it can have lifelong effects structurally & anatomically
48
What is appositional growth & when can it occur?
- growing bones widen as they lengthen
- occurs throughout life
49
Bones thicken in response to___
incr stress from muscle activity or added weight
50
What stimulates the growth factors?
- Growth hormone
- thyroid hormone
- testosterone/estrogen
51
52
Thyroid Hormone
Modulate & ensure proper amount of growth hormone & therefore bone growth
53
Growth Hormone
Stimulates growth at the epiphyseal plate in infancy & childhood
54
Testosterone (M) &Estrogen (F)
Promote adolescent growth spurts & end the growth of bones by **inducing epiphyseal plate closure** (at the end of adolescence)
55
Bone remodeling consists of both...
bone deposit (osteoblasts) & bone resorption (osteoclasts
56
Where does bone remodeling occur?
at surfaces of both periosteum & endosteum
57
Describe remodeling units
packets of adjacent osteoblasts & osteoclasts coordinate the remodeling process
58
Osteoclast activation involves...
PTH & immune T-cell proteins
59
Osteoblasts are activated by...
- mechanical signal
- incr Ca & phosphate ions
- appropriate amounts of alk phos
60
What does serotonin do?
inhibits bone growth
61
What does Leptin do?
opposes osteoblasts
- The more adipose tissue you have, may cause you to have more leptin, & could interfere w/ the bone remodeling
62
What stimulates bone remodeling?
- stressors
- physical activity
- hormones
- Ca++ levels
- Fitness
63
Calcium-homeostasis and bone breakdown has to do with
calcium-homeostasis & bone breakdown has to do with
64
What does calcitonin do?
- tones down Ca++
- stimulates building bone
- tones down the effects of the PTH
65
NOTE
You have high levels of Ca in the blood, so you want to tone down the amount of Ca in the blood, so you deposit it & make more bone
66
When does bone ossification first start occurring?
in utero
67
What happens to bone density as we age?
it decr
- esp postmeno women
68
What hormone mediates bone growth?
estrogen
69
Closure of the epiphyseal happens at what age?
18-25yo
70
Function of Vit D
helps absorb Ca++ in the small intestine
71
How long do you have to get sunlight exposure to maintain Vit D levels?
5 - 30 minutes
- depends on location, time of year
72
Who are more likely to have a lower Vit D levels?
- African Americans
- Breastfeeding /pregnant women
73
Function of ligaments
along w/ trunk muscles, help support vertebral column
74
Describe the anterior & posterior longitudinal ligaments?
continuous bands from neck to sacrum that run down front & back of spine
75
Function of anterior & posterior longitudinal ligaments?
Support & prevent hyperextension (backward) or hyperflexion (forward) bending
76
Function of ligamentum flavum
connects adjacent vertebrae
77
Function of short ligaments
connect each vertebra to those above & below
78
What are the two parts of the intervertebral discs?
- Nucleus pulposus
- Anulus fibrosus
79
Describe the nucleus pulposus
- Inner gelatinous nucleus
- Gives disc its elasticity & compressibility
80
Describe the annulus fibrosus?
- Outer collar composed of collagen & fibrocartilage
- Limits expansion of nucleus pulposus when compressed
81
What are joints?
sites where 2 or more bones meet
82
joints aka
articulations
83
Functions of joints?
give skeleton mobility & hold skeleton together
84
3 classifications of joints
- fibrous
- cartilaginous
- synovial
85
Why do we have fontanelles then sutures?
allows for growth of the brain
86
Example of syndesmoses (fibrous) joint
think b/t two bones
--> tibia & fibula
87
Example of a gomphoses (fibrous) joint
holding our teeth in gums
88
Criteria for cartilaginous joints
- Bones united by cartilage
- Like fibrous joints, have no joint cavity
- Not highly movable
89
What are the two types of cartilaginous joints?
- Synchondroses
- Symphyses
90
Criteria for a synovial joints
- bones separated by fluid-filled joint cavity
- All are diarthrotic (freely movable)
- Include almost all limb joints
91
What are the general features of synovial joints?
- articular (hyaline) cartilage
- joint (synovial) cavity
- articular (joint) capsule
--> 2 layers
- synovial fluid
92
Describe articular hyaline cartilage
consists of hyaline cartilage covering ends of bones
93
Function of articular (hyaline) cartilage
prevents crushing of bone ends
94
Describe the joint (synovial) cavity
small, fluid-filled potential space that is unique to synovial joints
- big area for infx!
95
What are the layers of articular (joint) capsule & their function?
- External **fibrous layer**: dense irregular CT
- Inner **synovial membrane**: loose CT that makes synovial fluid
96
Describe synovial fluid
viscous, slippery filtrate of plasma & hyaluronic acid
97
What is the function of synovial fluid?
- Lubricates & nourishes the articulate cartilage
- Contains phagocytic cells to make sure the joints stay sterile
98
What are bursae?
reduce friction where ligaments, muscles, skin, tendons, or bones rub together
99
What are tendon sheaths?
elongated bursae wrapped completely around tendons to reduce friction (can get inflammation called tendonitis)
100
What connects muscle to bone?
tendons
101
What connects bone to bone?
ligaments
102
What is extracapsular?
outside the capsule
103
What is intracapsular?
- deep to capsule
- covered by synovial membrane
104
What is capsular?
thickened part of fibrous layer
105
Function of ligaments?
stabilize the joint & help prevent hyperextension/hyperflexion
106
Nerves function...
- detect pain
- monitor joint position & stretch
107
Capillary beds function...
supply filtrate for synovial fluid
108
What are fatty pads?
cushioning b/t fibrous layer of capsule & synovial membrane or bone
109
What is an articular disc (menisci)?
Fibrocartilage separates articular surfaces to improve “fit” of bone ends, stabilize joint, & reduce wear and tear
110
Define origin
attachment to immovable bone
111
All muscles attach to bone or CT at no fewer than___
2 points
112
Define insertion
attachment to moveable bone
113
Muscle contraction causes ___ to move toward ___
- insertion
- origin
114
6 different types of synovial joints
- Plane
- Hinge
- Pivot
- Condylar
- Saddle
- Ball-and-socket
115
Movements occur along what planes?
transverse, frontal, or sagittal
116
Plane joint
Movement type:
Examples:
- nonaxial movement (gliding)
- intercarpal & intertarsal joints
- joints b/t vertebral articular surfaces
117
Hinge joint
Movement type:
Examples:
- Uniaxial movement (flexion & extension)
- elbow & interphalangeal joints
118
Condylar joint
Movement type:
Examples:
- biaxial movement (flex/ext & ab/ad duction)
- metacarpophalangeal (knuckle) & wrist joints
119
Pivot joint
Movement type:
Examples:
- uniaxial movement (rotation)
- proximal radioulnar & atlantoaxial joints
120
Saddle joint
Movement type:
Examples:
- biaxial movement (ab/ad duction & flex/ext)
- carpometacarpal joints of thumb
121
Ball-and-socket joint
Movement type:
Examples:
- multiaxial movement (flex/ext, ab/ad duction, rotation)
- shoulder & hip joints
