Download 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 _____________________________
__________________________________________________________________
10. A sarcomere is __________________________________________________
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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 connected to __________________________________
2. A motor neuron passes out 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 Theory
1. The functional unit of skeletal muscles is ______________________________
2. According to the sliding filament theory, when sarcomeres shorten, _________
__________________________________________________________________
3. As contraction occurs, ________________ and ______________ get narrower
and _____________________________________________ move closer together.
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E. Cross-bridge Cycling
1. The force that shortens the sarcomeres comes from ______________________
__________________________________________________________________
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 broken 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 _________________________________________________________
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6. ATP is necessary for both muscle ____________________________________
and _______________________________________________________________
7. The trigger for contraction is ________________________________________
G. Energy Sources for Contraction
1. Creatine phosphate is ______________________________________________
2. Creatine phosphate contains ________________________________________
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 _____________
_________________________________________________ as a source of energy
for synthesizing _____________________________________________________
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 ______________________________________________
__________________________________________________________________
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J. Muscle Fatigue
1. Fatigue is _______________________________________________________
2. Fatigue may result from ____________________________________________
__________________________________________________________________
3. A cramp is ______________________________________________________
4. Physically fit people make less lactic acid because _______________________
__________________________________________________________________
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 ____________________________________________
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8. An all-or-none response is __________________________________________
__________________________________________________________________
9. The length to which a muscle is stretched before stimulation affects _________
__________________________________________________________________
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, ________________ tend to be 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 ______________________________
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G. Types of Contractions
1. An isotonic contraction is __________________________________________
2. A concentric contraction is _________________________________________
3. An eccentric contraction is__________________________________________
4. An isometric contraction is _________________________________________
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. A muscles contain ____________________________________ 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 _____________________________________________________
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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 _____________________
__________________________________________________________________
3. Hormones affect smooth muscle by___________________________________
__________________________________________________________________
4. Stretching of smooth muscle can trigger _______________________________
5. Smooth muscle is _________________ to contract and ___________________
to relax 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. 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 __________________________________________________
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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.
C. Interaction of Skeletal Muscles
1. A prime mover is _________________________________________________
2. A synergist is ____________________________________________________
3. An antagonist is __________________________________________________
VII. Major Skeletal Muscles
A. Introduction
1. The name of a muscle may reflect ____________________________________
__________________________________________________________________
2. An example of a muscle named for it size is ____________________________
3. An example of a muscle named for its shape is __________________________
4. An example of a muscle named for its function is________________________
5. An example of a muscle named for its number of origins is ________________
6. An example of a muscle named for its attachments site is _________________
__________________________________________________________________
7. An example of a muscle named of the direction of its muscle fibers is _______
__________________________________________________________________
B. Muscles of Facial Expression
1. As a group, muscles of facial expression connect ________________________
__________________________________________________________________
2. For the following muscles, list their origins, insertions, and actions.
Epicranius
Orbicularis oculi
Orbicularis oris
Buccinator
Zygomaticus
Platysma
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C. Muscles of Mastication
1. Muscles of mastication produce____________________________ movements.
2. For the following muscles, list their origins, insertions, and actions
Masseter
Temporalis
Medial pterygoid
Lateral pterygoid
D. Muscles That Move the Head and Vertebral Column
1. For the following muscles, list their origins, insertions, and actions
Sternocleidomastoid
Splenius capitis
Semispinalis capitis
Erector spinae
E. Muscles That Move the Pectoral Girdle
1. For the following muscles, list their origins, insertions, and actions
Trapezius
Rhomboideus major
Levator spinae
Serratus anterior
Pectoralis major
F. Muscles That Move the Arm
1. For the following muscles, list their origins, insertions, and actions
Coracobrachialis
Pectoralis major
Teres major
Latissimus dorsi
Supraspinatus
Deltoid
Subscapularis
Infraspinatus
Teres minor
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G. Muscles That Move the Forearm
1. For the following muscles, list their origins, insertions, and actions
Biceps brachii
Brachialis
Brachioradialis
Triceps brachii
Supinator
Pronator teres
Pronator quadratus
H. Muscles That Move the Hand
1. For the following muscles, list their origins, insertions, and actions
Flexor carpi radialis longus
Flexor carpi ulnaris
Palmaris longus
Flexor digitorum profundus
Flexor digitorum superficialis
Extensor carpi radialis
Extensor carpi radialis brevic
Extensor carpi ulnaris
Extensor digitorum
I. Muscles of the Abdominal Wall
1. The linea aspera is ________________________________________________
2. For the following muscles, list their origins, insertions, and actions
External oblique
Internal oblique
Transversus abdominis
Rectus abdominis
J. Muscles of the Pelvic Outlet
1. The pelvic diaphragm forms ________________________________________
2. The urogenital diaphragm fills _______________________________________
3. For the following muscles, list their origins, insertions, and actions
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Levator ani
Coccygeus
Superficial transversus perinea
Bulbospongiosus
Ischiocavernosus
Sphincter urethra
K. Muscles That Move the Thigh
1. For the following muscles, list their origins, insertions, and actions
Psoas major
Iliacus
Gluteus maximus
Gluteus medius
Gluteus minimus
Pectineus
Adductor longus
Adductor magnus
Gracilis
L. Muscles That Move the Leg
1. For the following muscles, list their origins, insertions, and actions
Biceps femoris
Semitendinosus
Semimembranosus
Sartorius
Quadriceps femoris group
M. Muscle That Move the Foot
1. For the following muscles, list their origins, insertions, and actions
Tibialis anterior
Fibularis tertius
Extensor digitorum longus
Gastrocnemius
Soleus
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Flexor digitorum longus
Tibialis posterior
Fibularis longus
VIII. Life-Span Changes
A. Signs of aging of the muscular system begin to appear _________________________
B. At a microscopic level, ___________________________________________ decline.
C. _______________________________________ being to replace some muscle tissue.
D. _________________________________ can help maintain a healthy muscular system
E. According to the National Institute on Aging, exercise should include _____________
________________________________________________________________________
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