Unit 3 Flashcards
(104 cards)
1
Q
What are joints
A
articulations, sites where bones meet
2
Q
what are the functional classes of joints?
A
synarthroses: immovable (ex: skull sutures)
amphiarthrosis: partially movable (ex: pubic symphysis)
diarthroses: freely movable (ex: elbow)
3
Q
strutural classes of joints
A
fibrous joints: collagenous
cartilaginous joints: bones united by cartilage, no joint cavity, not highly movable
synovial joints: only structural classification of joints with a joint cavity
4
Q
describe the different types of fibrous joints
A
sutures: short collagen fibers connect the two bones, calcify w age
syndesmoses: long fibers (ex: between tibia/fibula and ulna/radius)
gomphoses: periodontal ligaments anchor tooth to joint
5
Q
describe the different types of cartilaginous joints
A
synchondrosis: hyaline cartilage, generally immovable (ex: rib 1 to manubrium and epiphyseal plate)
symphysis: fibrocartilage (ex: pubic symphysis and intervertebral disc)
6
Q
describe the different parts of synovial joints
A
1) Articular Capsule
-fibrous capsule of dense irregular connective tissue on external
-synovial membrane: secretes joint fluid, loose CT
2) Articular Cartilage: hyaline cartilage on ends of long bones for protection
-ligaments, tendons, bursae
3) Joint cavity: small fluid filled potential spaces
4) Synovial fluid: viscous lubricant
5) Reinforcing ligaments
6) nerves and blood vessels
7) Other important features: fatty pads, articular discs, menisci, burase, and tendon sheaths
-
7
Q
what are the types of synovial joints?
A
hinge: ulna to humerus, uniaxial
pivot: proximal radial-ulna joint, uniaxial
condylar: metacarpophalangeal, biaxial
ball and socket: shoulder, multiaxial
8
Q
joint origin
A
immovable part of joint
9
Q
joint insertion
A
movable part of joint
10
Q
flexion
A
decreases joint angle
11
Q
extension
A
increases joint angle
12
Q
hypertension
A
movement beyond anatomical position
13
Q
circumduction
A
making a cone with a limb
14
Q
abduction
A
away from midline
15
Q
adduction
A
toward midline
16
Q
rotation
A
turning bone around long axis, medial and lateral, ex: first 2 cervical vertabrae, hip, and shoulder
17
Q
gliding movements
A
short bone gliding past each other, ankles and wrist
18
Q
opposition of thumbs
A
to tips of other fingers
19
Q
pronation
A
radius crosses ulna, palm down
20
Q
supination
A
forearm bones become parallel
21
Q
dorsiflexion
A
lift foot up at ankle
22
Q
plantar flexion
A
point foot down
23
Q
elevation
A
lifting up superiorly, shrugging shoulders and scapula
24
Q
depression
A
lowering body part
25
inversion
sole of foot pointed medially
26
eversion
bottom of foot pointed laterally
27
retraction
pull back, ex: mandible/scapula
28
protraction
jut forward
29
Describe the shoulder joint
Diarthrotic(large ROM), synovial, ball in socket
30
what is the shoulder stabilized by
-glenoid labrum:fibrocartilage
-capsular ligaments: coracohumeral ligament, coracoacromial ligament, and acromial humeral ligament
-biceps brachii tendon and rotator cuff tendons: supraspinatus, infraspinatus, subscapularis, and teres minor
31
describe the hip joint
diarthrotic, synovial, ball in socket, femoral head goes into acetabulum of coxal bone
32
what is the hip stabilized by
acetabular labrum: fibrocartilage
ligaments: iliofemoral, pubofemoral, ischiofemoral, ligamentum teres
33
describe the knee joint
diarthrotic, synovial, hinge
34
What is within the knee joint
femoral condyles join with tibial condyles, menisci(pads of fibrocart on top of tibia), patellar facets(join w femur's patellar surface), ACL, PCL, LCL, MCL, and patellar ligament
35
describe skeletal muscle
striate, multiple nuclei per cell, voluntary
36
describe cardiac muscle
striate, one nucleus per cell, involunatry
37
describe smooth muscle
not striate, one nucleus per cell, involuntary
38
what are the functional characteristics of muscle tissue?
-excitability (voltage gated channels causing an AP)
-contractility (myosin pulling actin, can generate force and shorten muscle)
-extensibility(can be stretched without ripping)
-elasticity(springs back to preferred rest length after stretching)
39
Muscle functions
-move body segments and material through hollow organs
-posture
-generate heat
-stabilize joints
40
endomysium
wrapping for one cell/fiber
41
perimysium
around on fascile
42
epimysium
around one muscle fiber
43
fascia
around muscles
44
origin
proximal, part of muscle that attaches to muscle more proximally
45
insertions
part of muscle that attaches more distally, generally moves more when muscle contracts
46
tendons
ropes of collagen
47
aponeuroses
sheets of collagen
48
direct, fleshy attachments
epimysium fuses to periosteum
49
fascicle
bundle of fibers
50
sarcolemma
muscle cells cell membrane
51
T-tubules
tunnels from membrane surface that go into middle of cell and to it's organelles, conducts impulses/action potentials to middle of cell, rapid communication system that ensures each muscle fiber contracts at same time
52
sarcoplasmic reticulum
smooth ER, houses calcium, uses ATP to save Ca++ ions and contains Ca++ pumps
53
myofibrils
big organelles, make up most of cells cytoplasm, contain contractile filament proteins:actin and myosin, and bundles of myofilaments
54
thick filaments
~200 myosin molecules each, each myosin has 2 heads and a tail
55
thin filaments
-2 strands of actin, sites to for myosin to attach
-2 ribbons of tropomyosin, block binding cites in relaxed fiber, troponin acts as lock and hinge, Ca++ is key to starting contractions by binding to troponin which then pulls tropomyosin
56
list the parts of muscle from largest to smallest
muscle, fascicle, muscle fiber, myofibrils, myofilament, sarcomere
57
A-band
dArk, middle of sarcomere, think filament blocks light, M line in middle of H zone when muscle is relazed
58
H zone
light part in middle of dark band,
59
I-band
only thin filament, lIght part, z-disc in middle
60
z-disc
hold end of sarcomere, boarder between sarcomeres, dark sectio in middle of I band
61
sliding filament model
when muscle contracts all of it's sarcomeres shorten, as thin filaments slide toward center of sarcomere
62
neuromuscular junction (NMJ)
synapse: motor neuron contacts muscle cell
neurons axon terminal meets fiber's end plate
terminal has lots of stores of ACH packed in synaptic vesicles while end plate has ACH receptors
63
nerve impulse causes
1) voltage-gated Ca++ channels, Ca++ difuses into terminal of neuron
2) exocytosis of ACH
3) ACH diffuses across cleft
64
End-plate potential (EPP)
1) ACH binds to receptor it causes opening of receptors channel (Na+)
2) Na+ enters=depolarization= EPP
Later: ACH Esterase splits ACH to clear junction to allow for relaxation
65
action potential
-long distance messaging down sarcolemma and T-tubules
-involves voltage gated channels for Na+ and K+
-lasts only ~2 sec and spreads quickly
66
excitation-contraction coupling
action potential causes calcium to release from sarcoplasmic reticulum which leads to sliding filament model
(action potential to contraction)
67
crucial role of Ca++
Action potential travelled down T-tubule causing opening of Ca++ channels on SR, Ca++ can be released (within cell) to cytoplasm of muscle cell
some Ca++ binds to troponin
troponin pulls off of actin (removing tropomyosin blockade)
Later: Ca++ pump of SR pulls Ca++ back into vault
68
what are the steps of the cross-bridge cycle
1) attachment: myosin reaches across and attaches to actin
2) powerstroke: myosin pulls actin
3) detachment: ATP attaches to myosin, myosin relases actin
4) cocking of myosin: ATP is split to ADP and P, myosin head moves to high energy position
69
main steps of muscle contraction
1) motor neuron fires AP
2) motor neuron's axon terminal releases ACh into synaptic cleft, stimulated muscle fiber, causing depolarization
3) EPP triggers Ap that travel across sarcolemma
4) AP in sarcolemma travels to T-tubules and causes release of Ca++
5) Ca++ binds to troponin, releasing tropomyosin cover
6) myosin heads bind to actin and contraction occurs
70
motor unit
motor neuron and the muscle fibers it controls (150-500 fibers)
71
motor size unit dependent on
size of muscle, ex: smaller amount of fibers=finer control (eye and fingers)
larger amount of fibers=lesser control (quad)
72
a muscle twitch is
response of a whole muscle to a shock or stimulus
73
components of muscle twitch
1) latent phase: no force movement, AP and Ca++ movement
2) contraction phase: cross bridge cycling occurs
3) relaxation phase: tropomyosin blockade resumes, muscle returns to resting state, takes time and is more gradual
74
wave summation/rate of firing
-when multiple stimuli occur in rapid succession
-one twitch then builds on the last under high frequency rate (Hz)
-when force is sustained contraction=tetanus
75
multiple motor unit summation/recruitment of units
-activate several units @same time to generate large forces
-happens in size order: for low force, small units recruited, for high force small, medium, and large units recruited
76
isotonic contractions
muscle is changing length, constant force through movement, includes concentric (muscle shortening), and eccentric (muscle lengthening)
77
isometric
no movement of limb, load, weight, increase in force without length change
78
Creatine phosphate ATP replenishing
CP + ADP yields ATP + Creatine (with creatine kinase as catalyst)
10-15s worth of E
anaerobic
79
glycolysis
1 glucose yields 2 pyruvates, creating 2 ATP, lactic acid cycle to follow
30-60s of E
anaerobic, in cytosol
80
aerobic respiration
requires oxygen, pyruvate reacts w O2 in mitochondria to yield 32-36 ATP
81
fatigue is
decreased output due to recent activity
82
command fatigue
CNS origin of fatigue
83
muscle fatigue
high K+ in T-tubules that blocks it from communicating AP
84
Oxygen debt
extra O2 thats needs to be replenished
E stores back in body after exercise
85
force of muscle contraction is dependent on
1) number of muscle fibers stimulated:recruitment
2) size of muscle fibers: fatter cells have more filaments
3) rate of stimulation: frequency
4) length-tension relationship: more actin/myosin connections at rest length
86
Describe a red muscle fiber
Slow, oxidative, lots of capillaries, little glycogen stores, for long distance jogging
87
describe pink muscle fibers
fast, oxidative, moderate amount of capillaries, moderate glycogen stores, for tennis/vball
88
describe white muscle fibers
fast, glycolysis, little capillaries, lots of glycogen stores, for sprinting/lifting
89
what does aerobic/endurance exercise promote?
red fibers! Increased capillaries, myoglobin, and mitochondria
90
what does resistance exercise promote?
white fibers! Increased size of fibers by adding myofibrils and increased glycogen stores
91
smooth muscle size and shape
compared to skeletal muscle is small and has spindle shape
92
smooth muscle arrangment
two layers
-outer, longitudinal layer
-inner, circular layer
93
smooth muscle neural wiring
diffuse junction inputs from autonomic nervous system fibers that have varicosities where they release neurotransmitter
94
organelles and proteins within smooth muscle
-small SR
-no T-tubules
-no troponin (use calmodulin)
-dense bodies allow for attachment of contractile filaments to cell membrane
95
smooth muscle contraction is synchronous
neighboring cells fire and contract together, activity spreads from one to the next, connected via gap junctions
96
smooth muscle vs skeletal muscle contraction similarities
myosin pulls on actin, ATP required, Ca++ start process
97
smooth muscle vs skeletal muscle contraction differences
In smooth muscle contraction: mast of Ca++ comes into cell from extracellular fluid and binds to calmodulin to activate. Once calmodulin is activated, it activates a kinase which phosphorlyates myosin. Myosin pulls actin. Contraction tends to be much slower, likes to hold on longer so it burns less ATP, myosin grabs actin in opposing directions to shrink muscle
98
Regulation of contraction
-autonomic nerve endings can excite or inhibit smooth muscle
-hormones/local factors (adernaline, pH, O2, CO2)
99
Types of smooth muscle
-single unit SM(most common, have gap junction to stick together)
-multiunit SM ( only in select places, allows for finer control within more autonomic neurons ex: iris light rxn)
100
agonist
prime mover
101
antagonist
provides braking force
102
synergist
cooperates in supporting role
103
what are the components of a muscles name?
location, shape, size, fascicle/fiber arrangements, number of heads, location of attachments, and action
104
how can fascicles be arranged
parallel, convergent, pennate (uni/bi -pennate), circular, fusiform)
