CH 10 Flashcards
Muscle
1
Q
Types of muscle tissue
A
- Skeletal
- Cardiac
- Smooth
2
Q
Skeletal muscle AKA striated muscle
A
Attached to bones of the skeleton and some skin
3
Q
Muscle cells are AKA
A
Muscle fibers
4
Q
Skeletal muscle fiber characteristics
A
- Striated
- Voluntary
- Cylindrical
- Long
- Parallel
- Multinucleated
5
Q
Voluntary
A
Can control movement, however involuntary movements still occurs
6
Q
Only voluntary muscle
A
Skeletal muscle
7
Q
Smooth muscle
A
Found in wall of hollow organs, blood vessels, eye, arrector pili muscle
8
Q
Smooth muscle movement of blood vessels and eyes
A
Can control contraction/dilation
As a result, can control BP
9
Q
Hollow organs
A
Organs with a cavity
Stomach, intestine, uterus, urinary bladder
10
Q
Smooth muscle fiber characteristics
A
- Nonstriated
- Short
- Fusiform/spindle-shaped
- Mononucleated
- Involuntary
Shape of each muscle cell undefined since each one up against each other
11
Q
Smooth muscle looks similar to what tissue?
A
Dense regular CT
12
Q
Cardiac muscle
A
Only in myocardium
13
Q
Myocardium
A
Wall of heart
14
Q
Muscle fibers of cardiac muscle
A
- Striated
- Involuntary
- Mononucleated
- Short
- Branched
15
Q
Cardiac muscle fibers are attached end to end by strong desmosomes and gap junctions called __________
A
Intercalculated discs
16
Q
Intercalculated discs allow for what?
A
Rapid passage of electric current
17
Q
Characteristics of muscle tissues
A
- Excitability
- Contractibility
- Extensibility
- Elasticity
18
Q
Excitability
A
Ability to conduct electric currents (ions) along cell membrane
19
Q
Electric current
A
Action potential
20
Q
Contractibility
A
Ability for muscle cells to contract (shorten) to cause movement
21
Q
Elasticity
A
Ability for muscle cells to return back to “resting length” after stretching
22
Q
Extensibility
A
Ability for muscle cells to stretch without damage
23
Q
Muscular system
A
Only refers to skeletal muscle
24
Q
Function of muscular system
A
- Body movement
- Maintenance of posture
- Temperature regulation
- Storage and movement of materials
- Joint support
25
Body movement
Skeletal muscle is responsible for voluntary movement
26
Temperature regulation
Muscle contraction generates heat
27
Storage and movement of materials
Sphincter muscle expels waste
28
Joint support
Muscle crosses over joint
29
Layers of connective tissue associated with skeletal muscle
- Deep fascia
- Epimysium
- Perimysium
- Endomysium
30
Deep fascia
Dense irregular CT that surrounds the entire muscle
31
Mysium
Muscle
32
Epimysium
Thinner layer of dense irregular CT that surrounds the entire muscle
33
Perimysium
Dense irregular CT that surrounds the fasicles
34
Fasicle
Bundle of muscle fibers/cells
35
Endomysium
Areolar/loose CT that surrounds each muscle fiber
36
Muscle attachments
- Tendons
- Aponeuroses
37
Tendon
Cylindrical dense regular CT that connects muscle to bone
38
Aponeuroses
Flat, broad sheets of dense regular CT that connect muscle to bone or muscle to muscle
39
Muscle attachments
- Origin
- Insertion
40
Origin
Heavier attachment that is located closer to the trunk/torso
41
Insertion
Lighter attachment that is located further from the trunk/torso
42
Describe the movement of muscle attachments during contraction
Origin remains stationary during contraction
Insertion is pulled toward origin during contraction
43
Myo-
refers to muscle tissue
44
sarco-
refers to flesh
45
Plasma membrane
Sarcolemma
46
Cytoplasm
Sarcoplasm
47
Smooth ER
Sarcoplasmic reticulum (SR)
48
Organization of Skeletal muscle
- Muscle
- Fasicles
- Muscle fiber/cell
- Myofibrils
- Myofilaments
- Actin and myosin
49
Myofibril
Bundle of myofilaments
50
Myofilaments AKA filaments
Slide to cause contraction
51
Sarcoplasmic reticulum
Stores calcium ions -- necessary for contraction
52
Terminal cisterns
Tiny sacs in SR that stores calcium ions
53
Transverse (T) tubules
Carry action potential deep inside muscle cells like a wire
54
Triad
2 terminal cisterns/ terminal cisternae
1 transverse (T) tubule
55
Types of myofilaments
- Thick
- Thin
56
Thick myofilaments are composed of __________
myosin
57
Thin myofilaments are composed of what?
- Mainly actin
- Tropomyosin
- Troponin
58
Actin
Binds to myosin heads AKA crossbridge during contraction
59
Tropomyosin
Covers actin's binding site (active site) during relaxation
60
Troponin
Binds to calcium ions during contraction, moves tropomyosin off to prepare for contraction
61
Sarcomere
Functional unit of skeletal muscle
Repeating unit at which filaments organize themselves in to the entire length of the myofibril
Shortens during contraction
62
Describe the length of a sarcomere
Extends from one Z disc to another
63
Z disc
Attachment site for thin filaments
64
A band
Dark band in the middle of the sarcomere; composed of thick filament with overlapping thin filaments on the lateral ends
65
M line
Attachment site for thick filaments
66
H-zone
Lighter region in the middle of the A band; contains only thick filaments
67
I band
Light band containing only thin filaments and titin protein
68
Which parts of the sarcomere disappear during contraction?
i.e. Which parts of the sarcomere shorten or narrow during contraction?
H-zone and I band
69
What changes occur to the sarcomere during contraction?
- H zone disappears
- Width of A band stays constant
- I band narrows or shortens in length
- Z discs in one sarcomere come closer together
- Sarcomere narrows or shortens in length
70
Parts of a sarcomere
- A band
- H zone
- M line
- I zone
- Z disc
71
How do muscle fibers shorten?
By the interaction between thin and thick filaments within each sarcomere
72
Sliding filament theory
Mechanism for contraction
73
Why is skeletal muscle striated?
Dark bands are the A band
Light bands are the I band
74
Steps of Sliding Filament Theory
1) Action potential travels along the sarcolemma down the T-tubules
2) Calcium is released from the terminal cisterns of the sarcoplasmic reticulum (SR) and binds to troponin
3) Calcium-troponin complex moves tropomyosin off actin's binding sites
4) Myosin heads bind to actin. Filaments slide
5) Z discs come close together
75
Types of neurons
- Sensory
- Motor
76
Sensory neurons
Carries action potential to CNS
Responds to environment
77
Motor neurons
Carries action potential away from CNS to muscles or glands
78
Parts of a neuron
- Cell body
- Axon
- Dendrites
79
Neuron
Nerve cell that are specialized to detect stimuli, process information quickly, and rapidly transmit impulses from one region of the body to another
80
Cell body AKA soma
Houses the nucleus of neurons and most organelles; Controls the rest of the cell and proteins for the cell
81
Dendrite
Short, branched processes which receive incoming signals from other cells and transmit the information to the cell body
82
Axon
Long neuron process which carries the outgoing signals to other cells
In the context of the motor neuron, the axon carries action potential to muscle fibers
83
Synaptic knob/cleft
Expanded tip of an axon that contains synaptic vesicles
84
Synaptic vesicles
Tiny sacs filled with neurotransmitter ACh
85
Acetylcholine (ACh)
Neurotransmitter for skeletal muscle
86
Motor-end-plate
Specialized folded region of the sarcolemma (on muscle cell) that contains ACh receptors
87
Synaptic cleft
Narrow space between the motor-end-plate and synaptic knob
88
Synapse
Junction between a neuron and another neuron, muscle fiber, or gland
89
Neuromuscular/ myoneural junction
Synapse between a muscle fiber and motor neuron
90
Components of the neuromuscular junction
- Synaptic knob
- Motor-end-plate
- Synapatic cleft
91
Steps of Contraction
1) Action potential (AP) travels from cell body down to the axon of the motor neuron
2) ACh is released from synaptic vesicles
3) ACh binds to receptors on the motor-end-plate
4) AP is transmitted to muscle fiber along the sarcolemma and T tubule membranes
5) Calcium is released from SR into sarcolemma and binds to troponin on thin filaments
6) Calcium-troponin complex moves tropomyosin, exposing binding sites on actin
7) Myosin heads bind to actin, forming a crossbridge
8) Filaments slide, sarcomere shortens
92
Motor unit
Motor neuron and muscle fiber it synapses on
- Motor neuron
- Muscle fibers innervated by a single motor neuron
- Neuromuscular junctions
93
Innervate
Give supply to
94
How does muscle relaxation occur?
- Enzyme Acetylcholinesterase (AChE) breaks down excess ACh in synaptic cleft
- Calcium pumps returns calcium to terminal cisterns of SR
95
Qualities of muscle that are incorporated into naming muscles
- Muscle action
- Body region
- Muscle attachment
- Orientation of muscle fibers
- Muscle size, shape, length
- Muscle heads/tendons of origin
96
Naming - muscle action
- Adductor
- Abductor
- Extensor
- Flexor
97
Naming - body regions
- Oris (mouth)
- Cervicis (neck)
- Brachial (arm)
- Carpi (wrist)
- Pollicis (thumb)
- Gluteal (buttocks)
- Femoris (thumb)
- Hallucis (great toe)
- Anterior (toward front of body)
- Posterior/ dorsal/dorsi (toward back of body)
- Superior
- Inferior
- Superficialis (superficial)
- Profundus (deep)
98
Naming - muscle attachments
- Sternum and clavicle (cleido)
- Between ribs (intercostal)
- Subscapular fossa (subscapularis)
- Fibula (fibularis longus)
- Zygomatic bone (zygomaticus longus)
99
Naming - Orientation of muscle fibers
- Rectus (straight)
- Oblique (angled)
- Orbicularis (circular)
100
Naming- muscle shape and size
- Deltoid (triangular)
- Quadratus (rectangular)
- Longus (long)
- Brevis (short)
- Major (larger of 2 muscles)
- Minor (smaller of 2 muscles)
- Maximus (largest)
- Medius (medium sized)
- Minimus (smallest)
101
Naming - muscle heads/ tendons of origin
- Biceps (2 heads)
- Triceps (3 heads)
- Quadriceps (4 heads)
102
Muscle actions
- Flexion/ extension
- Abduction/ adduction
- Medial/ lateral rotation
- Protonation/ supination
- Inversion/ eversion
- Plantarflexion/ dorsiflexion
- Lateral flexion
- Elevation/ depression
- Protraction/ retraction
103
Flexion
Angle between articulating bones decrease
e.g. bend finger towards palm to make a fist, bend forearm towards arm at elbow
104
Extension
Angle between articulating bones increase
e.g. straightening fingers after making a fist, straightening arm and forearm
105
Lateral flexion
Vertebral column moves/bends laterally along coronal plane
e.g. bend left or right
106
Abduction
Lateral movement of a body part away from the midline
e.g. spreading digits, pointing hands and fingers laterally away from body
107
Adduction
Medial movement of a body part towards the midline
e.g. bring raised arm or thigh back to body, bring spread digits back to midline of hand
108
Circumduction
Combination of flexion, extension, abduction, adduction in succession; distal end of limb moves in a circle
109
Pronation
Rotation of forearm where palm is turned posteriorly
Radius and ulna cross to form an X
110
Supination
Rotation of forearm where palm is turned anteriorly
Radius and ulna are parallel
111
Depression
Movement of a body part inferiorly
e.g. opening mouth, move shoulders down
112
Elevation
Movement of a body part superiorly
e.g. opening mouth, shrugging shoulders (up)
113
Dorsiflexion
Talocrural/ankle joint movement where the dorsum (superior surface) of the foot is brought closer to the anterior surface of the leg
Essentially, move ankle up
114
Plantarflexion
Talocrural/ankle joint movement where the sole of the foot is brought to the posterior surface of the leg
Essentially, move ankle down
e.g. ballerina on toes- en pointe
115
Inversion
Turning the sole of the foot medially
116
Eversion
Turning the sole of the foot laterally
117
Protraction
Anterior movement of body part
e.g. huching shoulder by cross arms, sticking out chin
118
Retraction
Posterior movement of body part
e.g. sticking chin in
