1B - Joints, Cartilage, Muscles Flashcards
(136 cards)
1
Q
joints
A
areas where two or more bones join together
2
Q
fibrous joints
A
articulating bones connected by fibrous tissue in which there is almost no movement ex. sutures in skull
3
Q
cartilaginous joints
A
allow only slight movement and consist of bones connected entirely by cartilage (hyaline or fibrocartilage)
4
Q
synovial joints
A
created where two bones articulate to permit a variety of motions, have synovial fluid
5
Q
synchondroses
A
primary cartilaginous joint - early life bone development
ex. epiphyseal plates
6
Q
symphyses
A
secondary cartilaginous joint - strong, slightly moveable joints, united by fibrocartilage
ex. pubic symphysis
7
Q
saddle joint
A
synovial joint, found at the base of thumb; allows grasping and rotation
8
Q
ball and socket joint
A
synovial joint - hip and shoulder joints
- multi axial
- high mobility, low stability
- have labrum to improve joint contact
9
Q
condyloid joint
A
synovial joint, does everything except rotating (flexion, extension, adduction, abduction)
ex. wrist
10
Q
pivot joint
A
synovial joint, allows for rotation around the length of a bone, only allows rotation
ex. radial head next to ulna
11
Q
hinge joint
A
synovial joint between bones that permits motion in only one plane
ex. humerus and ulna at elbow
- uniaxial
- more stability, lower ROM
12
Q
plane joint
A
synovial joint that allows only gliding movement
ex. between carpals and tarsals
13
Q
what 5 structures make up synovial joints
A
bones, ligaments + capsules, tendons/muscles, intra-articular structures, bursae
14
Q
ligaments
A
connective tissue structures that bind bones together, non contractile
15
Q
simple joint
A
a joint with only two skeletal components
ex. elbow
16
Q
stability in joints
A
comes at expense of range of motion
17
Q
what are the 3 factors that affect stability + ROM
A
- shape and arrangement of articulating surfaces
- ligaments that cross the joint - more + tighter ligaments = more stability
- tone of surrounding muscles
18
Q
range of motion
A
the range through which a joint can be moved, comes at expense of stability
19
Q
complex joint
A
two surfaces with articular disc or fibrocartilage
ex. knee
20
Q
tendons
A
connect muscle to bone
21
Q
sprain
A
injury to a ligament
22
Q
strain
A
injury to muscle tendon
23
Q
non-contractile tissue
A
tissue that cannot actively shorten
ex. skin, ligament, cartilage
24
Q
grade 1 sprain
A
stretching or slight ligament tearing, mild tenderness, swelling, and stiffness
25
grade 2 sprain
incomplete tear with moderate pain, swelling, and bruising
26
grade 3 sprain
complete tear of ligaments with severe swelling, bruising, and instability
27
treatment of sprains
PRICE, Protection, Rest, Ice, Compression, Elevation
28
intra-articular structures
contribute to synovial joint function
29
extracapsular ligaments
reinforce capsule, stabilizing ligaments located outside joint capsule
30
intracapsular ligaments
within a joint but excluded from synovial cavity, stabilizing ligaments located inside joint capsule
31
articular discs
pads composed of fibrocartilage, minimize wear and tear on the bone surfaces. absorb shock and distribute weight
32
labrum
fibrocartilaginous lip extending from the edge of a joint to deepen the socket and improve bony contacts. common in ball and socket joints
33
bursa
fluid-filled sac that reduces friction between moving parts (bones and tendons, bones and ligaments, etc.)
- protect structures from each other
- fibrous capsules lined with synovial fluid
34
tendon sheaths
elongated bursa wrapped completely around tendon subjected to friction
35
bursitis
chronic inflammation of a bursa caused by irritation from repeated excessive exertion of a joint, trauma, acute chronic infection, or rheumatoid arthritis
36
suture
interlocking line of union between bones
37
gomphosis
fibrous joint, attachment of a tooth to its socket
38
syndesmosis
a fibrous joint at which two. bones are bound by long collagen fibres
ex. tib-fib
39
fibrocartilage
cartilage that contains fibrous bundles of collagen, very durable and strongest type of cartilage
ex. menisci, intervertebral disc, pubic symphysis
40
what is the function of fibrocartilage?
shock absorber, support and join structures
41
elastic cartilage
specialized tissue with abundant elastic fibres, more flexible than hyaline cartilage
ex. epiglottis, outer ear, eustachian tubes
42
what is. the function of elastic cartilage?
provides strength and elasticity to maintain shape of structures
43
hyaline/articular cartilage
has a smooth surface that provides flexibility and support at joints
found on the ends of long bones, ribs, and nose
- dense viscoelastic connective tissue
- covers the articulating ends of bones within synovial joints
44
most common and weakest cartilage
hyaline cartilage
45
what does hyaline/articular cartilage not have?
no blood supply, no lymph channels, no neurological supply
- important because makes injury hard to detect and can't repair on its own
46
what is the function of hyaline cartilage?
- distributes mechanical load over a wider area to decrease stress/pressure on joint surfaces
- reduce friction to minimize wear and allow relatively free movement of the opposing joint surfaces
47
composition of hyaline cartilage
cells (chondrocytes, less than 10%) and extracellular matrix
48
chondrocytes
mature cartilage cells
manufacture, secrete, organize and maintain ECM
49
extracellular matrix
the chemical substances located between connective tissue cells
- interstitial fluid (water, lipids, dissolved electrolytes)
- collagen
- proteoglycans
50
cartilage loading
compression forces interstitial fluid out of the cartilage into the joint capsule. when the load is removed, fluid flows back into the cartilage with new nutrients
51
what is the purpose of cartilage loading?
nutrient exchange and replenishment
52
cartilage is _________
avascular
53
osteoarthritis
unilateral "wear and tear" injury where joint cartilage is gradually lost, causing pain. Most common type of arthritis and cause of hip and knee replacements
54
rheumatoid arthritis
Bilateral, chronic autoimmune disorder in which the joints and some organs of other body systems are attacked. Inflammation of joint linings (synovial membrane) and cartilage. As cartilage degrades fibrous tissue joins exposed bone ends making them immovable
55
what are the 3 types of muscle
skeletal, cardiac, smooth
56
skeletal muscle
a muscle that is attached to the bones of the skeleton and provides the force that moves the bones, multi-nucleated, striated
57
skeletal muscles are under ___________ control
voluntary
58
cardiac muscle
involuntary muscle tissue found only in the heart, striated, single nucleus
59
smooth muscle
involuntary muscle found inside many internal organs of the body, viscera and blood vessels and skin
- not striated
- single nucleus
60
4 functions of muscle tissue
1. produce body movements
2. stabilizing body positions
3. producing heat (thermogenesis)
4. storing + moving substances in the body
61
4 properties of muscle tissue
1. electrical excitability - able to respond to stimuli
2. contractility - attached to bone via tendons
3. elasticity - returns to original length after contraction and extension
4. extensibility - can stretch without being damaged
62
myosin
the contractile protein that makes up the thick filaments of muscle fibers
63
actin
the contractile protein that makes up the thin filaments of muscle fibers
64
autorhythmicity
hearts ability to control its own contractions
65
electrical signals
audtorhythmicity in the heart
66
chemical signals
action potential signals received at neuromuscular cleft
67
periosteum
a dense fibrous membrane covering the surface of bones (except at their extremities) and serving as an attachment for tendons and muscles
68
fascicle
bundle of myofibres
69
myofibre
individual muscle cell
70
epimysium
covers the entire skeletal muscle
71
perimysium
the connective tissue that surrounds fascicles
72
endomysium
connective tissue surrounding a myofiber
73
myofibril
tightly packed filament bundles found within skeletal myofibres
74
sarcomere
a structural unit of a myofibril in striated muscle, consisting of a dark band and the nearer half of each adjacent pale band
75
Z line
the line formed by the attachment of actin filaments between two sarcomeres of a muscle fibre in striated muscle cells
- two sets of actin fibres are going to join together
76
M line
supporting proteins that hold the thick filaments together in the H zone
- where two sets of myosin fibres are going to join together
77
I band
region within myofibril where only actin is present
78
H band
region within myofibril where only myosin is present
79
A band
full length of where myosin is (can overlap with actin). always the same width
80
myosin heads
bind to specific sites on actin molecules to from cross bridges
- 2 heads
- actin binding head and ATP binding head
81
one myosin head binds to _____ and the other binds to ___
actin and ATP
82
tropomysin
form a long chain that cover "active sites" on a thin filament (actin); preventing actin-myosin interaction
83
upper motor neuron
originates in cerebral cortex or brainstem and terminates on a lower motor neuron. Brain to spinal cord
84
lower motor neuron
motor neuron in the peripheral nervous system with its nerve fibre extending out to the muscle and only its cell body in the central nervous system. Spinal cord to periphery
85
motor neurons
neurone that carry outgoing information from the brain and spinal cord to the muscles and glands
86
contralateral
defines how innervation is on the opposite side of the body
87
principle of orderly recruitment
the theory that motor units generally are activated on the basis of a fixed order of recruitment, in which the motor units within a given muscle appear to be ranked according to the size of the motor neuron
88
Henneman size principle
the recruitment of motor units within a muscle proceeds from small motor units to large motor units
89
low force contractions
small motor units recruited
90
high force contractions
large motor units recruited
91
force production
motor unit size + firing frequency
92
slow oxidative fibre
a type of muscle fibre that is the smallest in diameter, the least powerful, dark red in colour due to large amounts of myoglobin and many blood capillaries; it is a fatigue-resistant fibre adapted to maintain posture and for aerobic, endurance activities like running a marathon
93
fast glycolytic fibre
a type of muscle fibre that is the largest in diameter, the most powerful, and is pale in colour due to the low myoglobin content and few blood capillaries; adapted for intense anaerobic movements of short duration such as weight lifting
94
fast oxidative-glycolytic fibre
a type of muscle fibre that is intermediate in diameter and dark red in colour due to large amounts of myoglobin and many blood capillaries; used in walking and sprinting
95
Type 1
slow oxidative, slow fatigue rate, low force
96
type 2a
fast oxidative glycolytic, medium fatigue rate, medium force
97
type 2x
fast glycolytic, fast fatigue rate, high force
98
sliding filament theory
theory that actin filaments slide toward each other during muscle contraction, while the myosin filaments are still
- actin filaments slide over myosin, creating a shortening effect (Z disks move closer together)
99
cross-bridge formation
high-energy myosin head attaches to thin filament, which is a repetitive cycle producing muscle contraction
100
bound state
myosin has bound to actin and is stuck there
101
power stroke
release inorganic phosphate from myosin, causing a transformation
102
rigor state
inorganic compound has been removed, myosin has contracted, and is stuck
103
relaxed state
when ATP binds
104
binding state
cycle can be repeated
105
what element, when it binds to the troponin complex, makes tropomyosin roll away
calcium
106
troponin complex
the regulatory proteins that control the position of tropomyosin on the thin filament
107
what is the first step in excitation-contraction coupling
calcium release
108
force-length relationship
sliding filament sarcomere structure has implications for muscle force production. when a muscle is maximally activated, the isometric force that is produced is dependent upon muscle length
109
isometric force
the generation of force without muscle movement
110
ascending limb
sarcomeres shortened, mechanism for reduced force unknown. shorter limb = less force
111
plateau
optimal overlap of actin/myosin = maximal cross bridges = maximal force
112
descending limb
as length increases, fewer actin sites overlap myosin
113
passive muscle stretch
activates spindle stretch receptors and causes increased rate of action potentials in the afferent neuron
114
degree of muscle activation
number of active sarcomeres. Determines force produced
115
parallel elastic component
passive elasticity derived from muscle membranes
116
force-velocity relationship
as speed of contraction increases, the force it is able to exert decreases
117
isometric
high force, velocity = 0
- no movement
118
concentric
low force, high velocity, cross bridges can only go so fast
- shortening
119
eccentric
poorly understood
- lengthening
120
torque
force x moment arm. muscles can only produce so much force, but we can change the angle at which it acts and therefore change the moment arm
121
moment arm
perpendicular distance from an axis to the line of action of a force. changes depending on angle of insertion
122
sliding filament theory states (5)
1. bound state
2. power stroke
3. rigor state
4. relaxed state
5. binding state
123
pennation angle
angle at which muscle fibres all connect together in the tendon
124
unipennate muscle
all the muscle fibres are on the same side of the tendon
125
bipennate muscle
muscle fibres on both sides of the tendon; rectus femoris
126
multipennate muscle
has branches of the tendon within the muscle
127
grade 1 strain
overstretching leading to localized pain, minimal swelling, and tenderness
128
grade 2 strain
partial tearing of muscle or tendon
129
grade 3 strain
a palpable defect of the muscle, severe pain, an d poor motor function
130
symptoms of strains
swelling, bruising or redness, pain at rest, inability to use muscle or muscle weakness
131
first aid for strains
Protections
Rest
Ice
Compression
Elevation
132
fibrous connective tissue
dense tissue, large number of collagen fibres organized into parallel bundles
- includes ligaments and tendons
133
adipose
fat tissue
134
what age and onwards has progressive muscle loss with aging?
30
135
increased bone density
increased mineral density and calcium absorption increase bone strength as a result of weight-bearing activities, prevents osteoporosis
136
firing rate
the rate at which a neuron produces action potentials; usually expressed in terms of spikes per second
