Muscles Flashcards
(90 cards)
1
Q
derived from the Latin word meaning “mouse” (“mus”).
A
Muscles
2
Q
Study of muscles
A
Myology
3
Q
Muscle cells
A
Mycocytes
4
Q
Development of Muscles in the body
A
Myogenesis
5
Q
Muscle originates from the embryological tissue layer called the
A
mesoderm
6
Q
Cell membrane and external lamina
A
sarcolemma
7
Q
Cytoplasm of muscle cells
A
sarcoplasm
8
Q
Smooth Endoplasmic Reticulum of Muscle is called
A
sarcoplasmic reticulum
9
Q
The 3 types of muscles all perform the following
Major Functions:
A
- Movement of the Body
- Posture Maintenance
- Respiration
- Producing Body Heat
- Communication
- Constriction of organs
and vessels - Heartbeat
10
Q
responsible for major body movements
A
Movement of the Body
11
Q
constantly maintaining tone (sitting, standing)
A
Posture Maintenance
12
Q
contraction of muscles in the diaphragm when breathing
A
Respiration
13
Q
heat released as by-product of muscle contraction (thermoregulation)
A
Producing Body Heat
14
Q
- speaking, writing, body language
A
Communication
15
Q
helps propel food to digestive tract, excrete waste material
A
Constriction of organs and vessels
16
Q
contraction of the cardiac muscle propels blood to other organs
A
Heartbeat
17
Q
shortening forcefully
A
Contractility
18
Q
responding to electrical stimuli called Action Potentials
A
Excitability
19
Q
Action potentials in muscles are referred to as
A
muscle action potentials
20
Q
arising in the muscular tissue itself
A
Autorhythmic electrical signals
21
Q
such as neurotransmitters released by neurons, hormones, or changes in pH
A
Chemical stimuli
22
Q
- stretching beyond normal resting length but still being able to
contract
A
Extensibility
23
Q
springing back to its original resting length
A
Elasticity
24
Q
Attached to the skeleton; covers bone and cartilage
framework
A
SKELETAL MUSCLES
25
are found peripherally just under the sarcolemma
Elongated nuclei
26
Reserve Progenitor cells remains adjacent to most fibers of differentiated skeletal muscle.
satellite cells
27
dense irregular tissue surrounding
the external lamina of individual muscle fibers.
Endomysium
28
present in all types of muscle; seen well in skeletal muscle:
Layers of Connective Tissue
29
- thin connective tissue layer that
immediately surrounds each bundle of muscle
fibers termed a fascicle
Perimysium
30
external sheath of dense irregular
connective tissue, surrounds the entire muscle
Epimysium
31
elongated, multinuclear cells composed
of several myofibrils
Muscle fiber
32
long, cylindrical filament bundles in the
sarcoplasm of myocytes.
Myofibril
33
stimulates skeletal muscle to contract.
Somatic Motor Neuron
34
Blood Vessels
Arteries
Veins
Capillaries
35
supply Oxygen to muscle fibers
Capillaries
36
- membranous smooth ER in skeletal muscle fibers
Sarcoplasmic Reticulum
37
long fingerlike invaginations of the cell membrane
encircling each myofibril near the aligned
A- and I-band boundaries of sarcomeres
Transverse or T-tubules
38
expanded structures adjacent to each T-Tubule
Terminal cisternae
39
small protein structures within the myofibrils
Myofilaments or filaments
40
16 nm in diameter and 1–2 m long and composed mostly of the
protein myosin.
Thick filaments
41
- 8 nm in diameter and 1–2 m long and composed mostly of the
protein actin
Thin filaments
42
Filaments inside a myofibril are arranged in compartments called
sarcomeres
43
are the basic functional units of a myofibril
Sarcomeres
44
narrow, plate-shaped regions of dense
protein material separate one sarcomere from
the next
Z discs
45
the darker middle part of the
sarcomere which extends the entire length of the
thick filaments.
A band
46
Is a lighter, less dense area that
contains the rest of the thin filaments but no
thick filaments and a Z disc passes through the
center of each
I band
47
located in the center of each A band
contains thick but not thin filaments.
H zone
48
so named because it is at the middle of
the sarcomere; at the center of the H zone
M line
49
main component of thick
filaments and functions as a motor protein
in all three types of muscle tissue
Myosin
50
points toward the M line in the center
of the sarcomere. forming the shaft of the thick
filament.
Myosin Tail
51
project outward from the shaft in a
spiraling fashion, each extending toward the six thin
filaments.
Myosin Heads
52
Individual actin molecules join to
form an actin filament that is twisted into a
helix.
Actin
53
where a myosin head
can attach.
Myosin binding Site
54
Proteins that make up the Actin Myofilament:
G-actin
F- actin
55
globular subunit of actin
G-actin
56
fibrillary; chain of 200 G-actin
subunits
F- actin
57
covers active sites of G actin
Tropomyosin
58
has 3 Subunits
Troponin
59
Troponin 3 Subunits
Trop I (TnI) > regulates actin-myosin interaction
Trop C (TnC) > binds to Calcium
Trop T (TnT) > anchors troponin to actin
60
Structural protein connecting Z Disc to M Line; stabilizes thick filament position
Titin
61
Structural protein of Z Disc; attaches actin to titin
α-actinin
62
Structural protein of M line of Sarcomere; connects adjacent thick filaments
Myomysein
63
wraps around the entire length of thin filament; anchors Z Disc to thin filaments
Nebulin
64
links thin filaments of sarcomere to integral membrane proteins in sarcolemma
Dystrophin
65
- The point of contact of motor neuron axon branches with the muscle fiber.
- Also called Synapse
NEUROMUSCULAR JUNCTION
66
electrical signals carried by neurons that stimulate muscle fiber action
Action Potentials
67
Axon terminal
Presynaptic Terminal –
68
Space between presynaptic terminal and the muscle fiber
Synaptic Cleft
69
muscle plasma membrane
Motor End Plate
70
Spherical Sacs that contain the
neurotransmitter Acetylcholine
Synaptic Vesicle
71
– molecule that is released
allowing neuron to communicate with its target
Neurotransmitter
72
occurs as the overlapping thin and thick filaments of each sarcomere slide past one another.
Contraction
73
There are 3 pathways that working muscles use to regenerate ATP:
1. Direct phosphorylation of ADP by creatine phosphate
2. Aerobic pathway
3. Anaerobic glycolysis and lactic acid formation
74
are unique to cardiac muscle fibers. These are microscopic structures that are irregular transverse thickenings of the sarcolemma that connect the ends of cardiac muscle fibers to one another.
Intercalated discs
75
(single-unit) smooth muscle tissue
(more common type).
Visceral
76
is present in smooth muscle,
serving to enhance actin–myosin interactions
Tropomyosin
77
molecules may exist in equal number
as actin, and has been proposed to be a loadbearing protein.
Calponin
78
has been suggested to be involved in
tethering actin, myosin and tropomyosin, and
thereby enhance the ability of smooth muscle to
maintain tension.
Caldesmon
79
muscle that has the major
responsibility for causing a particular movement
Prime Mover
80
Muscles that oppose or reverse a
Movement
Antagonists
81
help prime movers by producing
the same movement or by reducing undesirable
movements
Synergists
82
specialized synergists. They hold
a bone still or stabilize the origin of a prime mover
so all the tension can be used to move the insertion
bone.
Fixators
83
Criteria of Naming Muscles:
1. Direction of Muscle Fibers
2. Relative Size of Muscle
3. Location of Muscle
4. Number of Origin
5. Location of Muscle’s Origin and
Insertion
6. Shape of the Muscle
7. Action of the Muscle
84
- Fascicles arranged in concentric rings
- Generalized as “Sphincters”
Circular
85
- Fascicles converge to toward a single tendon
insertion
Convergent
86
- Length of fascicles run parallel to the long axis
Parallel
87
- “Feather” pattern; fascicles attach obliquely to a
central tendon
Pennate
88
- Age-related reduction in muscle mass and
regulation of muscle function
- Loss of muscle fibers begins as early as 25
years of age and, by age 80, the muscle mass
has been reduced by approximately 50%,due
primarily to the loss of muscle fibers
Sarcopenia or Muscle Atrophy
89
- Rare autoimmune disease that can affect
muscles during adulthood
- Characterized by drooping upper eyelids,
difficulty in swallowing and talking, and
generalized muscle weakness and fatigability.
- Shortage of acetylcholine receptors at
neuromuscular junctions caused by antibodies
specific for acetylcholine receptors
Myasthenia Gravis
90
2 types of dystrophy
Duchenne type
Becker type
