4 Muscular System Flashcards
(90 cards)
1
Q
Muscle Function
A
- Produce Movement
- Maintain Posture and Body Position
- Stabilize joints
- Generate heat
- additional functions
2
Q
Skeletal muscle fibers are packaged into organs called _ that attach to the skeleton
A
skeletal muscles
3
Q
Skeletal Muscle cover our _ , they help form the smooth contours of the body.
A
bone and cartilage framework
4
Q
physical structure of
Skeletal muscle fibers
A
- large
- cigarshaped
- multinucleate cells
5
Q
Skeletal muscle is also known as _ and as
voluntary muscle
A
striated muscle
6
Q
Connective Tissues wrapping
wraps entire muscle
A
epimysium
7
Q
Connective Tissues wrapping the Muscle Fibers
wrapped in endomysium
A
muscle fiber
8
Q
Connective Tissues wrapping the Muscle Fibers
wrapped in perimysium
A
fascicle
9
Q
no striations and is
involuntary
A
smooth muscle
10
Q
found mainly in the walls of
hollow (tubelike) organs
A
smooth muscle
11
Q
- are spindle-shaped, uninucleate, and surrounded by scant endomysium and are arranged in two layers (circular and longitudinal)
- single, fusiform, no striations
A
smooth muscle
12
Q
- is striated, uninucleated and under involuntary control
- branching chains of cells
A
Cardiac Muscle
13
Q
are cushioned by small amounts of endomysium and are arranged in spiral or figure 8–shaped bundles
A
cardiac cell
14
Q
Cardiac muscle fibers are branching cells joined by special gap junctions called _
A
intercalated discs
15
Q
connective tissue components of skeletal muscle
A
- epimysium
- perimysium
- endomysium
16
Q
connective tissue components of cardiac muscle
A
endomysium attached to the fibrous skeleton of the heart
17
Q
connective tissue components of smooth muscle
A
endomysium
18
Q
regulation of contraction of skeletal muscle
A
voluntary via nervous system controls
19
Q
regulation of contraction of cardiac muscle
A
- involuntary
- internal heart pacemaker
- nervous system controls
- hormones
20
Q
regulation of contraction of smooth muscle
A
- involuntary
- nervous system controls
- hormones
- chemicals
- stretch
21
Q
speed of contraction of skeletal muscle
A
slow to fast
22
Q
speed of contraction of cardiac muscle
A
slow
23
Q
speed of contraction of smooth muscle
A
very slow
24
Q
rhythmic contraction of skeletal muscle
A
no
25
rhythmic contraction of cardiac muscle
yes
26
rhythmic contraction of smooth muscle
yes, in some
27
Microscopic Anatomy of Muscle
1. sarcomeres
2. myofilaments
3. sarcoplasmic reticulum
28
# Microscopic Anatomy of Muscle
structural and functional units of skeletal muscle
sarcomeres
29
# Microscopic Anatomy of Muscle
are the precise arrangements of even smaller structures within sarcomeres - thin and thick myofibrils
myofilaments
30
# Microscopic Anatomy of Muscle
interconnecting tubules and sacs that is used to store calcium and to release it on demand when the muscle fiber is stimulated to contract
sarcoplasmic reticulum
31
Special functional properties of muscle fibers
1. irritability
2. contractility
3. extensibility
32
# Skeletal Muscle Fiber Activity
* aka responsiveness
* ability to receive and respond to stimulus
irritability
33
# Skeletal Muscle Fiber Activity
the ability to forcibly shorten when adequately stimulated
contractility
34
# Skeletal Muscle Fiber Activity
the ability of muscle fibers to stretch, whereas elasticity is their ability to recoil and resume their resting length after being stretched
extensibility
35
# Muscle Contraction
Skeletal muscle fibers must be stimulated by _
nerve impulses
36
# Muscle Contraction
* _ may stimulate a few muscle fibers or hundreds of them, depending on the particular muscle and the work it does
* A _ consists of one neuron and all the skeletal
muscle fibers it stimulates
* One motor neuron (nerve cell)
* motor unit
37
# Muscle Contraction
**Neuromuscular junction**s, contain synaptic vesicles filled with **neurotransmitter** which stimulates skeletal muscle fibers is _.
Acetylcholine or Ach
38
# Contraction of Muscle as Whole
Muscle law states that:
a “muscle fiber will contract
to its fullest extent when it is stimulated adequately;
it _"
never partially contracts
## Footnote
However, the whole muscle reacts to stimuli with **graded responses**, or different degrees of shortening, which generate different amounts of force
39
Graded Muscle Contraction is generated by:
1. by changing the **frequency** of muscle **stimulation**
2. by changing the **number** of muscle fibers **being stimulated** at one time.
40
What Fueled Muscle Contraction?
1. direct phosphorylation (creatine phosphate CP and ADP)
2. aerobic pathway (glucose)
3. anaerobic pathway (glycolysis and lactic acid formation)
41
Types of Muscle
Contraction
1. isotonic contractions
2. isometric contractions
42
# types of muscle contraction
the myofilaments are successful in their sliding movements, the muscle shortens, and movement
occurs.
isotonic contractions
43
# types of muscle contraction
examples of isotonic contractions.
* Bending the knee
* lifting weights
* smiling
44
# types of muscle contraction
the myosin filaments are “spinning their wheels,” and the tension in the muscle keeps increasing. They are trying to slide, but the muscle is pitted against some more or less immovable object.
isometric contractions
45
# types of muscle contractions
example of isometric contractions
* when you push the palms of your hands together in front of you, your arms and chest muscles are contracting isometrically.
46
the maintenance of partial
contraction of a muscle, important for generating
reflexes, maintaining posture and balance, and controlling proper function of other organ systems.
Muscle tone
47
controlled by the sensory muscle spindle,
which **measures muscle stretch**
Tone
## Footnote
applicable to skeletal, cardiac, smooth muscles
48
The continuous and passive partial contraction of the muscles, which helps maintain _
posture
49
# Effects of Exercise
results in stronger,
more flexible muscles with greater resistance to fatigue
Aerobic exercise, or endurance exercise
## Footnote
* because the blood supply to the muscles increases, and the individual muscle fibers form more mitochondria and store more oxygen.\
* Aerobic exercise helps us reach a steady rate of ATP production and improves the efficiency of aerobic respiration
50
# Effects of Exercise
require very little time and little or no
special equipment
Resistance exercises
## Footnote
* The increased muscle size and strength that result are due mainly to enlargement of individual muscle fibers (they make more contractile myofilaments) rather than to an
increase in their number.
* The amount of connective tissue that reinforces the muscle also increases
51
# Direction of the muscle fibers.
oblique in a muscle’s name tells you that the muscle fibers run obliquely (_ ) to the imaginary line
at a slant
52
# Direction of the muscle fibers.
the _ is the
straight muscle of the thigh.
rectus femoris
53
# Direction of the muscle fibers.
When a muscle’s name includes the term _ , its fibers or whole structure run parallel to that imaginary line.
rectus (straight)
54
# Direction of the muscle fibers.
Some muscles are named in reference to some _ , usually the midline of the body or the long axis of a limb bone.
imaginary line
55
largest muscle of the
gluteus muscle group
gluteus maximus
56
# name of muscle
1. largest
2. smallest
3. long
1. maximus
2. minimus
3. longus
57
# based on the bone
muscle on:
1. temporal bones
2. frontal bones
1. temporalis
2. frontalis
58
# muscle name
based on number of origins
1. biceps = 2
2. triceps = 3
3. quadriceps = 4
59
# muscle name after their attachment sites
* on sternum and clavicle, and inserts on the mastoid process of the temporal bone
sternocleidomastoid
## Footnote
sternum - sterno
clavicle - cleido
60
# named based on shape of muscle
triangular muscle on shoulder
deltoid
Greek letter delta (Δ)
61
# named based on action of muscle
1. adduction of thigh
2. extends muscles of the wrist
1. adductor
2. extensor
62
# Muscles
4 Arrangement of the
Fascicles
1. Circular pattern
2. Convergent Muscle
3. Parallel Arrangement
4. Pennate Pattern
63
# Arrangement of the Fascicles
* Fascicles are arranged in concentric rings
* typically found surrounding external body openings which they close by contracting, creating a valve (sphincters = squeezers)
* ex: orbicularis muscles around eyes and mouth
circular pattern
64
# Arrangement of the Fascicles
1. the fascicles converge toward a single insertion tendon
2. is triangular or fan-shaped,
3. ex: the pectoralis major muscle of the anterior thorax
convergent muscle
65
# Arrangement of the Fascicles
* the length of the fascicles run parallel to the long axis of the muscle, as in the sartorius of the anterior thigh.
* These muscles are straplike
* its fusiform modification results in a spindle- shaped muscle with an expanded belly (midsection) and tapered ends
* ex: biceps brachii muscle of the arm
parallel arrangement
66
# Arrangement of the Fascicles
short fascicles attach obliquely to a central tendon. In the extensor digitorum muscle of the leg
pennate pattern
67
# Arrangement of the Fascicles
If the fascicles insert from several different sides, the muscle is _
multipennate
68
# Arrangement of the Fascicles
If the fascicles insert into opposite sides of the tendon, the muscle is _
bipennate
69
# Arrangement of the Fascicles
the fascicles insert into only one side of the tendon, and the
muscle is _
unipennate
70
Types of Muscle
Movement
1. flexion
2. extension
3. rotation
4. abduction
5. adduction
6. circumduction
71
Special Movements
1. dorsiflexion and plantar flexion
2. inversion and eversion
3. supination and pronation
4. opposition
72
# Types of Muscle Movement
* generally in the sagittal plane
* decreases the angle of the joint
* brings two bones closer together
* typical of hinge joints (bending the knee or elbow),
* also common at ball-and-socket joints (for example, bending forward at the hip)
flexion
73
# Types of Muscle Movement
* movement that increases the angle, or distance, between two bones or parts of the body (straightening the knee or elbow).
* greater than 180° (as when you move your arm posteriorly beyond its normal anatomical position, or tip your head
extension
74
# Types of Muscle Movement
* movement of a bone around its longitudinal axis
* common
movement of ball-andsocket joints and describes the movement of the atlas around the dens of the axis
rotation
75
# Types of Muscle Movement
* moving a limb away (generally in the frontal plane) from the midline, or median plane
* fanning movement of your fingers or toes when they are
spread apart
abduction
76
# Types of Muscle Movement
* it is the movement of a limb toward the body midline
* as
“adding” a body part by bringing it closer to the trunk
adduction
77
# Types of Muscle Movement
* is a combination of flexion,
extension, abduction, and adduction commonly seen in ball-and-socket joints, such as the shoulder.
* proximal end of the limb is stationary, and its distal end moves in a circle
circumduction
78
# Special Movement
1. Up-and-down movements of the foot at the ankle are given special names
* Lifting the foot so that its superior surface approaches the shin (pointing your toe toward your head)
* pointing the toes away from your head is
1. Dorsiflexion and plantar flexion
* Dorsiflexion
* plantar flexion
79
# Special Movement
* Dorsiflexion of the foot corresponds to _ and _ of the hand at the wrist,
* whereas plantar flexion of the foot corresponds to _ of the hand.
extension and hyperextension
flexion
80
# Special Movement
* are also special movements of the foot
* To _ the foot, turn the
sole medially, as if you were looking at the bottom of your foot.
* To _ the foot, turn the sole
laterally.
invert/ inversion
evert/ eversion
81
# Special Movement
movement of the radius around ulna:
* turning backward
* turning forward
* supination (forearms rotates laterally, palm faces anteriorly)
* pronation (forearm rotates medially, palm faces posteriorly)
82
# Special Movement
* In the palm of the hand, the saddle joint between metacarpal 1 and the carpals allows _ of the thumb
* thumb touches other fingers of the same hands
* makes human hand a fine tool for grasping and manipulating objects
opposition
83
# Interactions of Skeletal Muscles in the Body
In general, groups of muscles that produce opposite
movements lie on _ of a joint.
opposite sides
84
# Interactions of Skeletal Muscles in the Body
Muscles are arranged so that whatever one muscle (or
group of muscles) can do, other muscles can _
reverse
85
# Interactions of Skeletal Muscles in the Body
Muscles can’t _ —they can only _ as they contract— so
most often body movements result from two or more
muscles acting together or against each other.
push
pull
86
Interactions of Skeletal Muscles in the Body
1. prime mover
2. antagonist muscle
3. synergist
4. fixators
87
# Interactions of Skeletal Muscles in the Body
* are 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
88
# Interactions of Skeletal Muscles in the Body
help prime movers by producing the same movement or by reducing undesirable movements.
Synergist
89
# Interactions of Skeletal Muscles in the Body
Muscles that oppose or reverse a movement
Antagonist Muscle
90
# Interactions of Skeletal Muscles in the Body
muscle that has the major responsibility for causing a particular movement
Prime Mover
