Download VI. Skeletal Muscle Actions

Shier, Butler, and Lewis: Hole’s Human Anatomy and Physiology, 11th ed.
Chapter 9: Muscular System
Chapter 9: Muscular System
I. Structure of a Skeletal Muscle
A. Introduction
1. A__________________________________ is an organ of the skeletal system.
2. A skeletal muscle is composed of ____________________________________
B. Connective Tissue Coverings
1. Fascia is ________________________________________________________
2. A tendon is ______________________________________________________
3. Tendons connect a muscle to ________________________________________
4. An aponeurosis is _________________________________________________
5. Epimysium is ____________________________________________________
6. Perimysium is____________________________________________________
7. A fascicle is _____________________________________________________
8. Endomysium is___________________________________________________
9. Deep fascia is ____________________________________________________
10. Subcutaneous fascia is ____________________________________________
11. Subserous fascia is _______________________________________________
C. Skeletal Muscle Fibers
1. A skeletal muscle fiber is a single ____________________________________
2. The sarcolemma is ________________________________________________
3. The sarcoplasm is _________________________________________________
4. The sarcoplasm contains ___________________________________________
5. Myofibrils are _________________ and are located in the ________________
6. Myofibrils play a fundamental role in _________________________________
7. Thick myofilaments are composed of _________________________________
8. Thin myofilaments are composed of __________________________________
9. The organization of myofilaments produce _____________________________
__________________________________________________________________
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10. A sarcomere is __________________________________________________
11. Myofibrils may be thought of as _____________________ joined end to end.
12. I bands are composed of __________________________________________
13. Z lines are ______________________________________________________
14. A bands are composed of __________________________________________
15. The H zone is ___________________________________________________
16. The M line is ___________________________________________________
17. Titin connects ___________________________________________________
18. A sarcomere extends from one _____________________________________
19. Each myosin molecule consists of ___________________________________
__________________________________________________________________
20. Thin filaments consist of double ____________________________________
21. Actin has a binding site to which ___________________________ can attach.
22. Troponin and tropomyosin associate with _____________________________
23. Sarcoplasmic reticulum is _________________________________________
24. Transverse tubules are ____________________________________________
25. Cisternae are____________________________________________________
26. A triad is formed by ______________________________________________
II. Skeletal Muscle Contraction
A. Neuromuscular Junction
1. Each skeletal muscle is functionally connected to ________________________
2. A motor neuron passes outward from _________________________________
3. Normally, a skeletal muscle fiber contracts only upon ____________________
__________________________________________________________________
4. A neuromuscular junction is ________________________________________
5. A motor end plate is _______________________________________________
6. A motor unit is ___________________________________________________
7. A synaptic cleft separates___________________________________________
8. Synaptic vesicles store _____________________________________________
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B. Stimulus for Contraction
1. __________________________ is the neurotrasnmitter that motor neurons use
to control skeletal muscle.
2. ACh is synthesized in the cytoplasm of ________________________________
and is stored in _____________________________________________________
3. When a nerve impulse ________________________ , acetylcholine is released
into the synaptic cleft.
4. ACh combines with ____________________________ on the motor end plate,
and stimulates ______________________________________________________
5. A muscle impulse is _______________________________________________
6. A muscle impulse changes __________________________________________
7. Ultimately the muscle impulse reaches ________________________________
C. Excitation Contraction Coupling
1. The sarcoplasmic reticulum has a high concentration of ___________________
2. In response to a muscle impulse, the membranes ________________________
___________________________, and the calcium ________________________
__________________________________________________________________
3. When a muscle fiber is at rest, ________________________ block the binding
sites on the actin molecules.
4. Calcium ions bind to ____________________, changing its _______________
and altering ________________________________________________________
5. The movement of the tropomyosin molecule exposes _____________________
__________________________, allowing________________________________
D. The Sliding Filament Model of Muscle Contraction
1. The functional unit of skeletal muscles is ______________________________
2. According to the sliding filament model, when sarcomeres shorten, _________
__________________________________________________________________
3. As contraction occurs, ________________ and ______________ get narrower
and _____________________________________________ move closer together.
E. Cross-bridge Cycling
1. The force that shortens the sarcomeres comes from ______________________
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__________________________________________________________________
2. A myosin cross-bridge attaches to actin in order to _______________________
__________________________________________________________________
3. The cross-bridge can release, straighten, and combine with ________________
__________________________________________________________________
4. Myosin cross-bridges contain the enzyme ______________________________
5. ATPase catalyzes _________________________________________________
6. The force for muscle contraction is provided by _________________________
__________________________________________________________________
7. Breaking down of ATP puts the myosin cross-bridge in a __________position.
8. When a muscle is stimulated to contract, a ____________________ attaches to
___________________________ and pulls ______________________________ ,
shortening the ______________________________________________________
9. When another ATP binds, the ______________________________ is released,
then breaks down the ____________________to return to ___________________
10. The cross-bridge cycle may repeat over and over as long as _______________
__________________________________________________________________
F. Relaxation
1. In order for a muscle fiber to relax, acetylcholine must be decomposed by an
enzyme called ______________________________________________________
2. The action of acetycholinesterase prevents _____________________________
__________________________________________________________________
3. When acetylcholine is breaks down, __________________________________
____________________________________________________________ ceases.
4. The calcium pump moves calcium ___________________________________
__________________________________________________________________
5. When calcium is removed from the cytoplasm, the _______________________
break and _____________________________________ rolls back into its groove,
preventing _________________________________________________________
6. ATP is necessary for both muscle ____________________________________
and _______________________________________________________________
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7. The trigger for contraction is ________________________________________
G. Energy Sources for Contraction
1. Creatine phosphate is ______________________________________________
2. Creatine phosphate includes ________________________________________
3. As ATP is decomposed to ADP, the energy from ________________________
is transferred back to ________________________________________________
4. After creatine phosphate is used, a muscle cell must depend on _____________
____________________________to synthesize ___________________________
5. Typically a muscle stores glucose in the form of ________________________
H. Oxygen Supply and Cellular Respiration
1. Glycolysis occurs _______________________ and is ____________________
2. Glycolysis releases a few ___________________________________________
3. The complete break down of glucose occurs in __________________________
and requires ________________________________________________________
4. The citric acid cycle and electron transport chain produce _________________
__________________________________________________________________
5. Oxygen is carried in the blood stream bound to _________________________
6. Myoglobin is _____________________________________________ in color.
7. Myoglobin stores ___________________________________ in muscle tissue.
I. Oxygen Debt
1. Lactic acid threshold is ____________________________________________
2. Under anaerobic conditions, glycolysis breaks down glucose into ___________
and converts it to ____________________________________________________
3. Lactic acid is carried by the blood to the _______________________________
4. Liver cells can convert lactic acid to __________________________________
5. Oxygen debt reflects ______________________________________________
__________________________________________________________________
J. Muscle Fatigue
1. Fatigue is _______________________________________________________
2. Fatigue may result from ____________________________________________
__________________________________________________________________
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3. A cramp is ______________________________________________________
4. The strenuous exercise of aerobic training _____________________________
__________________________________________________________________
K. Heat Production
1. Heat is a by-product of_____________________________________________
2. Blood transports heat _____________________________________________ ,
which helps ________________________________________________________
III. Muscle Responses
A. Introduction
1. One way to observe muscle contraction is to____________________________
__________________________________________________________________
2. An________________________ is usually used to produce muscle contraction.
B. Threshold Stimulus
1. Threshold stimulus is ______________________________________________
2. An impulse in _______________________________ normally releases enough
______________________ to bring the muscle fibers in its __________________
to ________________________________________________________________
C. Recording a Muscle Contraction
1. A twitch is ______________________________________________________
2. A myogram is ____________________________________________________
3. Three periods of a muscle fiber contraction are__________________________
__________________________________________________________________
4. During the period of contraction, a muscle fiber is _______________________
__________________________________________________________________
5. The latent period is________________________________________________
6. The period of relaxation is __________________________________________
7. The refractory period is ____________________________________________
8. An all-or-none response is __________________________________________
__________________________________________________________________
9. The length to which a muscle is stretched before stimulation affects _________
__________________________________________________________________
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10. If a muscle is stretched well beyond its normal resting length, the force will
__________________________________________________________________
11. At very short muscle lengths, the sarcomere becomes ___________________
and ___________________________________________________ is not possible.
12. In the whole muscle, the degree of tension reflects ______________________
__________________________________________________________________
D. Summation
1. Twitches in a muscle can combine to become ___________________________
2. Summation is ____________________________________________________
3. Tetanic contractions are ____________________________________________
E. Recruitment of Motor Units
1. The _______________ in the motor units, the more ______________________
the movements can be produced in a particular muscle.
2. All muscle fibers in a motor unit are stimulated at __________________ time.
3. Multiple motor unit summation is ____________________________________
4. Recruitment is ___________________________________________________
5. As the intensity of stimulation increases, ______________________________
continues until all possible motor units are activated in a muscle.
F. Sustained Contractions
1. During sustained contractions, ______________________ are recruited earlier.
2. The larger motor units respond ______________________________________
and more __________________________________________________________
3. Muscle movements are smooth because _______________________________
__________________________________________________________________
4. Muscle tone is ___________________________________________________
5. Muscle tone is important for maintaining ______________________________
G. Types of Contractions
1. An isotonic contraction is __________________________________________
2. A concentric contraction is _________________________________________
3. An eccentric contraction is__________________________________________
4. An isometric contraction is _________________________________________
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5. An example of an isometric contraction is _____________________________
6. An example of an isotonic contraction is _______________________________
H. Fast and Slow Twitch Muscle Fibers
1. Type I fibers are __________________________________________________
2. Examples of type I fibers are ________________________________________
3. Type I fibers are _________________ in color because ___________________
__________________________________________________________________
4. Type I fibers are resistant to_________________________________________
5. Type IIa fibers are ________________________________________________
6. Type IIa fibers are ________________ in color because __________________
__________________________________________________________________
7. Type IIb fibers are ________________________________________________
8. All muscles include ___________________________________ of fiber types.
IV. Smooth Muscles
A. Smooth Muscle Fibers
1. Compared to skeletal muscle fibers, smooth muscle fibers _________________
__________________________________________________________________
2. Two major types of smooth muscle are ________________________________
__________________________________________________________________
3. Multiunit smooth muscle is located ___________________________________
__________________________________________________________________
4. Visceral smooth muscle is located ____________________________________
__________________________________________________________________
5. Fibers of visceral smooth muscle are connected by_______________________
6. Rhythmicity is ___________________________________________________
7. Peristalsis is _____________________________________________________
8. Peristalsis helps force ______________________________________________
B. Smooth Muscle Contraction
1. Compared to skeletal muscle fibers, smooth muscle fibers lack _____________
and use _______________________________________ to bind calcium instead.
2. Two neurotransmitters that affect smooth muscle are _____________________
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__________________________________________________________________
3. Hormones affect smooth muscle by___________________________________
__________________________________________________________________
4. Stretching of smooth muscle can trigger _______________________________
5. Smooth muscle is slower to_________________ and ____________________
than skeletal muscle.
6. Unlike skeletal muscle, smooth muscle fibers can change length without
changing __________________________________________________________
V. Cardiac Muscle
A. Cardiac muscle appears only in ___________________________________________
B. Cardiac muscle is composed of _______________________________________ cells,
forming fibers that are ______________________________________________________
C. Cardiac muscle fibers can contract ___________________ then skeletal muscle fibers.
D. Intercalated discs are ____________________________________________________
E. Intercalated discs allow muscle impulses to __________________________________
F. A syncytium is _________________________________________________________
VI. Skeletal Muscle Actions
A. Introduction
1. Skeletal muscles generate __________________________________________
2. The action of each muscle mostly depends upon_________________________
__________________________________________________________________
B. Body Movement
1. Bones and muscles interact as _______________________________________
2. The four basic components of a lever system are ________________________
__________________________________________________________________
3. In scissors, the _____________________________________ form a rigid bar.
4. The fulcrum of scissors is __________________________________________
5. The resistance of scissors is _________________________________________
6. The force of scissors is supplied by ___________________________________
7. In a first class lever system, the parts are arranged _______________________
__________________________________________________________________
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8. Besides scissors, other examples of first class lever systems are ____________
__________________________________________________________________
9. In a second class lever system, the parts are arranged _____________________
__________________________________________________________________
10. An example of a second class lever system is __________________________
11. In a third class lever system, the parts are arranged _____________________
__________________________________________________________________
12. An example of a third class lever system is ____________________________
13. In the action of bending the upper limb at the elbow, the rigid bar is _______ ,
the fulcrum is ____________________, the resistance is ___________________ ,
and the force is applied by ____________________________________________
14. Bending the arm at the elbow is an example of a _______________________
class lever system.
15. When the upper limb straightens at the elbow, the rigid bar is ____________ ,
the pivot is _____________________, the resistance is ____________________ ,
and the force is applied by ____________________________________________
16. Straightening the arm at the elbow is a first class lever system because ______
__________________________________________________________________
17. An example of a second class lever system in the body is ________________
__________________________________________________________________
C. Origin and Insertion
1. The origin of a muscle is ___________________________________________
2. The insertion of a muscle is _________________________________________
3. When a muscle contracts, its ________________________________________
is pulled toward its __________________________________________________
4. The head of a muscle is ____________________________________________
5. The origins of the biceps brachii are __________________________________
6. The insertion of the bicep brachii is ___________________________________
7. When the biceps brachii contracts, the __________________________ bends.
D. Interaction of Skeletal Muscles
1. A prime mover is _________________________________________________
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2. A synergist is ____________________________________________________
3. An antagonist is __________________________________________________
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