2nd LQ - generalities of muscles (Jajurie) Flashcards
1
Q
Muscle cells, often called _____________because they are long
and narrow when relaxed, are specialized contractile cells.
A
muscle fibers
2
Q
Three types of muscle are
described based on distinct characteristics :
A
- Whether it is normally willfully controlled (voluntary vs. involuntary).
- Whether it appears striped or unstriped when viewed under a microscope (striated vs. smooth or unstriated).
- Whether it is located in the body wall (soma) and limbs or makes up the hollow organs (viscera, e.g., the heart) of the
body cavities or blood vessels (somatic vs. visceral).
3
Q
three muscle types:
A
- Skeletal striated muscle
- Cardiac striated muscle
- Smooth muscle
4
Q
is voluntary somatic muscle that makes up the gross skeletal muscles that compose the muscular system, moving or stabilizing bones and other
structures (e.g., the eyeballs)
A
Skeletal striated muscle
5
Q
is involuntary visceral muscle that forms most of the walls of the heart and adjacent parts of the great vessels, such as the aorta, and pumps blood.
A
Cardiac striated muscle
6
Q
is involuntary visceral muscle that forms part of the walls of most vessels and hollow organs (viscera), moving substances through
them by coordinated sequential contractions
A
Smooth muscle (unstriated muscle)
7
Q
coordinated sequential contractions
A
(pulsations or peristaltic contractions)
8
Q
white non-contractile portions of skeletal muscles
A
tendons
9
Q
- Large, very long,
- unbranched,
- cylindrical fibers with
- transverse striations (stripes)
- arranged in parallel bundles;
- multiple, peripherally located nuclei
A
Skeletal striated
muscle
10
Q
- Intermittent (phasic) contraction above a
baseline tonus; - acts primarily to produce
movement (isotonic contraction)
through shortening
(concentric contraction) - or controlled relaxation (eccentric
contraction), - or to maintain position against gravity or
other resisting force without movement
(isometric contraction)
A
Skeletal striated muscle
11
Q
Intermittent contraction above a
baseline tonus;
A
phasic
12
Q
acts primarily to produce
movement (isotonic contraction)
through shortening
A
concentric contraction
13
Q
controlled relaxation
A
eccentric contraction
14
Q
to maintain position against gravity or
other resisting force without movement
A
isometric contraction
15
Q
where is cardiac striated muscle found?
A
Muscle of heart
(myocardium)
adjacent portions of great vessels (aorta, vena cava)
16
Q
- Branching and anastomosing
shorter fibers with transverse striations
(stripes) - running parallel and connected
end to end by complex junctions (intercalated discs); - single, central nucleus
A
Cardiac striated muscle
17
Q
type of activity of Cardiac striated muscle
A
Strong, quick,
continuous rhythmic contraction;
acts to pump blood from heart
18
Q
- Involuntary; intrinsically (myogenically) stimulated and propagated;
- rate and strength of contraction
modified by “autonomic nervous system”
A
Cardiac striated muscle
19
Q
Voluntary (or reflexive) by “somatic nervous system”
A
Skeletal striated muscle
20
Q
Involuntary by autonomic nervous system
A
Smooth (unstriated or unstriped)
muscle
21
Q
- Walls of hollow viscera and blood vessels,
- iris, and ciliary body of eye;
- attached to hair follicles of skin (arrector
muscle of hair)
A
Smooth (unstriated or unstriped) muscle
22
Q
Single or agglomerated small,
spindle-shaped fibers without striations;
single central nucleus
A
Smooth (unstriated or unstriped) muscle
23
Q
- weak, slow, rhythmic, or sustained
tonic contraction; - acts mainly to propel substances
(peristalsis) - and to restrict flow (vasoconstriction and
sphincteric activity)
A
Smooth (unstriated or unstriped) muscle
24
Q
more proximal, less mobile attachment /stable
A
origin
25
more distal. more mobile attachment
insertion
26
fleshy part of the muscle
belly
27
The ends of a muscle are attached to supporting elements (bones, cartilage, ligaments, or other muscles) by cords of fibrous tissue called ____________
tendons
28
Some tendons form a thin, strong sheet that anchor the muscle to the skeleton
(e.g .. those belonging to the flat, wide abdominal oblique muscles)
Aponeurosis
29
an interdigitation of the tendinous ends of fibers of flat muscles
raphe
30
mesoderm developed into:
epimere
mesomere
hypomere
31
epimere develop into:
dermatome
sclerotome
myotome
32
dermatome:
dermis of skin
33
sclerotome:
skeletal system
34
myotome:
voluntary muscles
35
mesomere:
reproductive system
36
hypomere:
branchial/branchiomeric muscles
37
All of the branchiomeric muscles that come from the 1st branchial arch are innervated by the _____________________
trigeminal nerve
38
branchiomeric muscles that come from the 1st branchial arch:
M, aD, My, Tt, Tv
all the muscles of mastication,
the anterior belly of the digastric,
the mylohyoid,
tensor tympani and
tensor veli palatini.
39
All of the branchiomeric muscles of the 2nd branchial arch are innervated by the ____________________.
facial nerve
40
branchiomeric muscles of the 2nd branchial arch:
F, pD, Sm, Sm me
muscles of facial expression,
the posterior belly of the digastric,
stylohyoid muscle and the
stapedius muscle of the middle ear
41
There is only one muscle of 3rd branchial arch, the _______________.
stylopharyngeus
42
The stylopharyngeus is innervated by the _________________ nerve.
glossopharyngeal
43
All the brachial muscles of the 4th and 6th arches are innervated by the ___________________.
vagus nerve
44
brachial muscles of the fourth and sixth arches:
P, Ph, L
the muscles of the palate (exception of the tensor veli palatini )
all the muscles of the pharynx (except stylopharyngeus)
and all the muscles of the larynx
45
tensor veli palatini is innervated by the ______________
trigeminal nerve
46
stylopharyngeus is innervated by the ___________
glossopharyngeal nerve
47
muscles developing from somite myotome:
1. Epaxial muscle
2. Hypaxial muscle
48
skeletal muscle which lie DORSAL to the vertebral column
epaxial muscle
49
epaxial muscle in humans, is only a small group form by ____________, ____________, & ______________ muscles
transversospinalis,
longissimus, and
iliocotalis muscles
50
epaxial muscle at the ribcage level: ____________ muscle involved in rib elevation during respiration
levatores costarum
51
skeletal muscles lying VENTRAL to the vertebral column
these muscles contribute both body (trunk) and limb skeletal muscle
Hypaxial muscle
52
Hypaxial muscle include _________, _______, ___________, & ________
vertebral muscles
diaphragm
abdominal muscles
all limb muscles
53
functions of muscles:
1. Movement (locomotion)
2. Heat Generation
3. Shape and Contour
4. Stabilizes joint
5. Maintaining Posture
54
Movement: Skeletal muscles contract and pull on bones to generate ___________________at joints.
movement
55
Muscle contraction requires energy and produces ______________ as a byproduct of metabolism.
heat
56
Contours on the Lateral thorax of a woman
- pertoralis major
- teres major
- latissimus dorsi
- serratus anterior
- rectus abdominis
57
Muscles may be described or classified according to their shape, for which a muscle may also be named:
1. Flat muscles
2. Pennate muscles
3. Fusiform muscles
4. Convergent muscles
5. Quadrate muscles
6. Circular or sphincteral muscles
7. Multiheaded or multibellied muscles
58
have parallel fibers often with an aponeurosis—for example, the external oblique
Flat muscles
59
example of flat muscle:
sartorius - a narrow flat muscle with
parallel fibers.
60
are feather-like (L. pennatus, feather) in the arrangement of their fascicles, and may be uni, bi, or multi
Pennate muscles
61
example of unipennate
extensor digitorum longus
62
example of bipennate:
rectus femoris
63
example of multipennate:
deltoid
64
are spindle shaped with a round, thick belly (or bellies) and tapered ends
Fusiform muscles
65
example of Fusiform muscles
biceps brachii
66
arise from a broad area and converge
to form a single tendon
Convergent muscles
67
example of Convergent muscles
pectoralis major
68
have four equal sides (L. quadratus, square)
Quadrate muscles
69
example of Quadrate muscles
rectus abdominis, between its tendinous intersections
70
surround a body opening or orifice, constricting it when contracted
Circular or sphincteral muscles
71
example of Circular or sphincteral muscles
orbicularis oculi (closes the eyelids
72
have more than one head of attachment or more than one contractile belly, respectively
Multiheaded or multibellied muscles
73
74
Biceps muscles have two heads of attachment
example:
biceps brachii
75
triceps muscles have three heads
example:
e.g., triceps brachii
76
multibellied muscles having 2 bellies:
digastric and gastrocnemius
77
certain aspects of skeletal muscles
activity are automatic (reflexive) and therefore not voluntarily controlled
Reflexive Contraction
78
example of Reflexive Contraction:
- respiratory movements of the diaphragm
- myotatic reflex
79
Even when “relaxed,” the muscles of a conscious individual are almost always slightly contracted
gives the muscle a certain firmness, assisting
the stability of joints and the maintenance of posture, while keeping the muscle ready to respond to appropriate stimuli
Tonic Contraction
80
slight contraction, does not produce movement or active resistance
muscle tone (tonus)
81
is usually absent only when unconscious (as during deep sleep or under general anesthesia) or after a nerve lesion resulting in paralysis
Muscle tone
82
There are two main types of phasic (active) muscle contractions:
(1) isotonic contraction
(2) isometric contraction
83
the muscle changes length in relationship to
the production of movement
isotonic contraction
84
muscle length remains the same —no movement occurs, but the force (muscle tension) is increased above tonic levels to resist gravity or other antagonistic force
isometric contraction
85
two types of isotonic contractions:
1. concentric contraction
2. eccentric contraction
86
movement occurs as a result of the muscle shortening—for example, when lifting a cup, pushing a door, or striking a blow
ex. exceptional force applied by an athlete is what distinguishes it from an amateur
concentric contraction
87
contracting muscle lengthens—that is, it undergoes a controlled and gradual relaxation while continually exerting a (diminishing) force, like playing out a rope
eccentric contraction
88
when the prime mover is undergoing a concentric contraction,
its _________ is undergoing a coordinated eccentric contraction
antagonist
89
In walking, we contract _________________to pull our center of gravity forward and then, as it passes ahead of the limb,
we contract _____________to prevent a lurching during the transfer of weight to the other limb
concentrically
eccentrically
90
the structural unit of a muscle is a ______________
skeletal striated muscle fiber
91
the functional unit of a muscle is a _______________, consisting of a motor neuron and the muscle fibers it controls
motor unit
92
Large motor units, in which one neuron supplies several hundred muscle fibers, are in the ___________ and __________
large trunk
thigh muscles
93
the motor units include only a few muscle fibers are found in:
smaller eye
hand muscles
94
Chief muscle / main muscle (or member of chief group) responsible for producing a specific movement of the body
prime mover (agonist)
95
It contracts CONCENTRICALLY to produce the desired movement, doing most of the work (expending most of the energy) required
prime mover (agonist)
96
example of prime mover (triceps and biceps):
- Triceps in extension of the forearm
- Biceps brachii in flexion of the elbow
97
steadies the PROXIMAL parts of a limb through ISOMETRIC contraction while movements are occurring in distal parts.
fixator
98
This is a muscle that contracts isometrically (increases muscle tone but produces no movement) to stabilize the origin of the prime mover so that it can act efficiently.
Fixator
99
complements the action of a prime mover
synergist
100
synergist providing a weaker or less mechanically advantaged component of the same movement
directly assisting prime mover
101
synergist serving as a fixator of an intervening joint when a prime mover passes over more than one joint, for example.
indirectly assisting prime mover
102
is a muscle that opposes the action of another muscle
antagonist
103
A primary antagonist directly opposes
the prime mover,
but __________ may also be opposed by secondary antagonists.
synergists
104
As the active movers CONCENTRICALLY contract to produce a movement,
_________ ECCENTRICALLY contract, relaxing progressively in coordination to produce a smooth movement.
antagonists
105
acts to maintain contact between the articular surfaces of the joint it crosses (i.e., it resists dislocating forces);
shunt muscle
106
nerves supplying skeletal muscle
motor nerves
107
Partial state of contraction of muscles while resting
Muscle Tone
108
is the amount of tension (or resistance to movement) in muscles. Our muscle tone helps us to
hold our bodies upright when we are sitting and standing. Changes in muscle tone are what enable
us to move.
MUSCLE TONE
109
Consists of a motor neuron in the anterior gray horn or column of the spinal cord and all the muscle fibers it supplies
Motor Unit
110
The nerve enters the muscle at about the midpoint on its deep surface, often near the margin.
The point of entrance is known as the __________
motor point
111
The individual motor neurons within a muscle nerve supply a variable number of muscle fibers that are arranged in a variable spatial distribution.
A single motor neuron plus all the muscle fibers innervated by that neuron
Motor Unit
112
size of motor unit that are features of precision movement muscles such as the "extraocular muscles" and the "small muscles in the hand"
Small motor units (as few as 5 to 10 muscle fibers per neuron)
113
Disuse atrophy of the thoracic and abdominal muscles can result in
poor ____________
respiratory movements
114
The ______________ is the first part of the quadriceps muscle to atrophy in knee joint disease and the last to recover.
vastus medialis
115
In old age, the _______________ atrophy, resulting in a loss of height and a gradual return of the vertebral column to a continuous anterior concavity
intervertebral discs
116
The atrophy after menopause is caused by the absence of ovarian ______________ & ________________
estrogens and progesterone
117
_______________ or muscle wasting, is the loss of muscle mass and strength that occurs when muscles are not actively used or subjected to mechanical loading over an extended period of time.
Disuse atrophy, also known as muscle atrophy
118
This can happen for various reasons, including immobilization due to injury, illness, or prolonged bed rest.
Disuse atrophy, also known as muscle atrophy
119
CRANIAL NERVE MNEMONICS
OOOTTAFVGVAH
120
What is the longest Cranial Nerve?
VAGUS Nerve
121
What is the smallest muscle?
Some say that the STAPEDIUS muscle is the smallest located in your ear.
But the SMALLEST muscle is The
ARRECTOR PILI muscle which is responsible for giving you goosebumps
122
also called sensory
neurons, are the nerve fibers responsible for bringing sensory information from the outside world into the brain.
Afferent neurons
123
also called motor neurons, are the nerve fibers responsible for
carrying signals from the brain to the
peripheral nervous system in order to initiate an action.
Efferent neurons
124
basic system present throughout spinal cord:
1. Dorsal roots carry afferent fibers
2. Ventral roots carry efferent fibers.
3. Similarly, the ventral horn contains efferent cell bodies, and the dorsal root ganglion contains afferent cell bodies
125
MNEMONIC- SAD DAVE:
Sensory = Afferent = Dorsal
Dorsal = Afferent | Efferent = Ventra
126
The nerve trunk is a mixed nerve
_________ which also contains
sympathetic fibers
60 % motor and 40 % sensory
127
are found entirely within the body part upon which it acts,
Intrinsic muscles
128
originate outside of the part where it is found or upon which it acts, attached to different body segments, with at least one (1) point of attachment inside the body or part upon which it acts and at
least one (1) attachment outside.
Extrinsic muscles
129
Extrinsic Muscles of the Eye:
● Levator palpebrae superioris
● Superior oblique muscle
● Superior rectus muscle
● Medial rectus muscle
● Lateral rectus muscle
● Inferior oblique muscle
● Inferior rectus muscle
(4 recti muscles, 2 oblique muscles + 1 levator palpebrae
superioris)
130
________ muscles of the eye are situated outside the eyeball (Extraocular muscles), voluntary.
Extrinsic
131
__________ of the eye are situated inside the
eyeball (Intraocular muscles), involuntary.
Intrinsic muscles
132
_____of the eye are situated inside the
eyeball (Intraocular muscles), involuntary
Intrinsic muscles
133
-is a movement disorder that causes sudden, unintended, and uncontrollable jerky movements of the arms, legs, and facial muscles.
is seen in many diseases
and conditions and is caused by an
overactivity of the chemical dopamine in the areas of the brain that control movement.
“Para kang nagbre-break dance” (Jajurie, 2023).
Chorea
134
-is a hyperkinetic involuntary movement disorder characterized
by intermittent, sudden, violent, involuntary, flinging, or ballistic high amplitude movements involving
the ipsilateral arm and leg caused by
dysfunction in the central nervous system of the contralateral side
Hemiballismus
135
____________ refers to inflammation of the spinal cord. It can damage the insulating material, called myelin, that covers nerve cell fibers.
_____________refers to the pattern of changes in sensation—there is often a band-like sensation across the trunk of the body, with sensory changes below that area
Myelitis
Transverse
136
