Muscle Histology Flashcards
1
Q
function of muscle
A
- motion and stability
- internal organ function
- maintains body temperature
2
Q
motion and stability muscle function
A
- moves skeleton
- maintains posture
3
Q
internal organ muscle function
A
- digestive (peristalsis)
- cardiac (heartbeat)
4
Q
maintaining body temperature function
A
-muscle contraction (normal body temperature)
5
Q
characteristics of muscle
A
- irritability
- contractility
- extensibility
- elasticity
6
Q
irritability muscle characteristic
A
-receive and respond to stimulus from a neuron
7
Q
contractility muscle characteristic
A
-respond by contracting (shortening)
8
Q
extensibility muscle characteristic
A
-following contraction
9
Q
define contraction
A
-a muscle will extend to its original length
10
Q
elasticity muscle characteristic
A
-muscle will assume its desired shape after stretching
11
Q
structure of muscle tissue
A
- composed of fibers
- fibers contain “contractile proteins”
12
Q
muscle tissue fiber composition
A
-long, thing cells of muscle tissue
13
Q
muscle tissue contractile proteins
A
- actin and myosin
- cells can shorten and produce movement
14
Q
classifications of muscle
A
- skeletal
- smooth
- cardiac
15
Q
skeletal muscle classification
A
- long multinucleated and striated
- attached to skeleton
- voluntary (under conscious control)
16
Q
smooth muscle classification
A
- composed of long cells containing one nucleus
- found in GI tract and blood vessel walls
- involuntary (not under conscious control)
17
Q
cardiac muscle classification
A
- composed of uni-nucleated branching cells; end-to-end
- found only in heart
- involuntary
18
Q
skeletal muscle components
A
- associated connective tissue
- microscopic structure
- muscle contraction
19
Q
skeletal muscle associated CT components
A
- attachments
- coverings
20
Q
skeletal muscle attachments components
A
- tendons
- aponeurosis
21
Q
skeletal muscle tendon attachments
A
- dense regular connective tissue
- muscle to bone
22
Q
skeletal muscle aponeurosis
A
- dense regular connective tissue
- thin, tendinous sheet
23
Q
skeletal muscle coverings components
A
- endomysium
- perimysium
- epimysium
- fascia
24
Q
skeletal muscle covering composition
A
- organization of muscle
- tubes within tubes within tubes
25
define fascicle
-made of muscle cells (fibers)
26
skeletal muscle endomysium covering
-loose CT covering individual muscle fibers (muscle cells)
27
skeletal muscle perimysium covering
-surrounds bundles of muscle fibers (fascicles)
28
skeletal muscle epimysium covering
-covers entire muscle belly
29
skeletal muscle fascia covering
-CT which binds several muscle groups together
30
define a muscle fiber
-a single skeletal muscle cell
31
skeletal muscle microscopic characteristics
- multinucleated
| - contain numerous specialized cellular organelles
32
skeletal muscle microscopic structure components
- sarcoplasm
- sarcolemma
- t-tubule
- sarcoplasmic reticulum
- mitochondria
- myofibril
- myofilament
- myoglobin
- sarcomere
33
skeletal muscle sarcoplasm
-cytoplasm within muscle cells
34
skeletal muscle sarcolemma
- plasmalemma (cell membrane)
| - just deep to endomysium
35
skeletal muscle t-tubule
- tube-like extension of sarcolemma
| - transmits nerve impulse to sarcoplasmic reticulum
36
skeletal muscle sarcoplasmic reticulum
- basically smooth ER of muscle
- stores a large amounts of calcium
- when releases calcium triggers contraction
37
skeletal muscle mitochondria
- provide energy (ATP) via aerobic respiration
| - ATP provides the energy to allow myosin to form crossbridges with the actin
38
skeletal muscle myofibril
-"contractile organelles"
39
skeletal muscle myofilament
- in myofibrils
| - contain contractile proteins
40
skeletal muscle myoglobin
-red protein: contains iron, stores oxygen
41
skeletal muscle sarcomere
- many sarcomeres within myofibrils
- smallest contractile unit
- extends from Z band to Z band
42
define contractile organelles
-cylindrical units run entire length of muscle
43
components of myofilaments
- actin filaments
| - myosin filaments
44
skeletal muscle actin filaments
- thin filaments
| - closer to each end of sarcomere (near each Z line)
45
skeletal muscle myosin filaments
- thick filaments
- center of the sarcomere
- pulls actin inward (Z lines contracts)
46
skeletal muscle muscle contraction I band
- light band
- contains actin
- Z band located in the middle of the I band
47
skeletal muscle contraction A band
- dark band
| - contains both actin and myosin
48
skeletal muscle sliding filament mechanism
- initiated by the release of the neurotransmitter acetylcholine from a nerve fiber**
- results in the release of calcium within the muscle fiber which binds to the thin actin filaments
49
innervations of skeletal muscle
- neuromuscular junction
| - motor unit
50
skeletal muscle neuromuscular junction
-point of contact between muscle fiber and axon of neuron which stimulates it
51
skeletal muscle motor unit "all or nothing" principle
-when a nerve impulse travels through a motor unit all of the fibers served by it contracts simultaneously to their maximum
52
first step in muscle excitation
-motor neuron releases neurotransmitter acetylcholine (ACh)
53
second step in muscle excitation
-ACh triggers action potential in sarcolemma (muscle cell membrane
54
third step in muscle excitation
-change in sarcolemma--> release of calcium ions from sarcoplasmic reticulum
55
fourth step in muscle excitation
-sarcomeres shorten--> myofibrils shorten--> muscle fibers shorten--> muscle contract
56
types of muscle fibers
- red slow twitch fibers
- white fast twitch fibers
- intermediate fast twitch fibers
57
myoglobin muscle fibers red slow twitch fibers
-high
58
myoglobin muscle fibers white fast twitch fibers
-little
59
myoglobin muscle fibers intermediate fast twitch fibers
-high
60
mitochondria muscle fibers red slow twitch fibers
-many
61
mitochondria muscle fibers white fast twitch fibers
-few
62
mitochondria muscle fibers intermediate fast twitch fibers
-many
63
capillaries muscle fibers red slow twitch fibers
-many
64
capillaries muscle fibers white fast twitch fibers
-few
65
capillaries muscle fibers intermediate fast twitch fibers
-nany
66
what is the function of capillaries?
-deliver blood and oxygen
67
energy production muscle fibers red slow twitch fibers
-aerobic metabolism for ATP production
68
energy production muscle fibers white fast twitch fibers
- anaerobic pathways for ATP production
| - ->lactic acid is by-product
69
energy production muscle fibers intermediate fast twitch fibers
-aerobic
70
glycogen reserves muscle fibers red slow twitch fibers
-none
71
glycogen reserves muscle fibers white fast twitch fibers
-ranges
72
glycogen reserves muscle fibers intermediate fast twitch fibers
-N/A
73
power muscle fibers red slow twitch fibers
- high power
| - sustained over a long period of time
74
power muscle fibers white fast twitch fibers
-generates powerful contraction
75
power muscle fibers intermediate fast twitch fibers
-powerful (less than white fast twitch)
76
fatigue muscle fibers red slow twitch fibers
-fatigue resistant
77
fatigue muscle fibers white fast twitch fibers
-quickly
78
fatigue muscle fibers intermediate fast twitch fibers
-fatigue resistant (between red and white)
79
contraction time muscle fibers red slow twitch fibers
-contrast slowly for long periods of time
80
contraction time muscle fibers white fast twitch fibers
-fast contraction time
81
contraction time muscle fibers intermediate fast twitch fibers
-between red and white
82
examples of red slow twitch fibers
-posture (steady, prolonged contraction)
83
examples of white fast twitch fibers
- eye movement
- lifting
- throwing
84
examples of intermediate fast twitch fibers
-muscles of lower limbs (support and movement)
85
synergistic
-two or more muscles working together
86
antagonistic
-two or more muscles working against one another
87
concentric contraction
- causes tension on your muscle
| - as it shortens, it generates enough force to move an object
88
concentric contraction example
- bicep curl
| - lifting a weight
89
eccentric contraction
-motion of an active muscle while it is lengthening under load
90
eccentric contraction example
-lowering a weight
