Chapter 1: Structure and Function of Body Systems Flashcards
(242 cards)
1
Q
Fill in the blanks: ( ) contains the hint.
The skeletal muscles are under the control of the a)________ (what part of the brain?), which activates the skeletal muscle cells or fibers through the b)_________ _________ (nerve cells) of the peripheral nervous system.
A
a) cerebral cortex
b) motor neurons
2
Q
Fill in the blanks:
Support for neuromuscular activity involves continuous delivery of a)__________ and __________ to working tissues and removal of b)_________ and metabolic __________ from working tissues through activities of the c)___________ and ___________ systems.
A
a) oxygen; nutrients
b) carbon dioxide; waste by-products
c) cardiovascular; respiratory
3
Q
Fill in the blanks:
The musculoskeletal system consists of a)__________, b)__________, c)__________ and d)__________.
A
a) bones
b) joints
c) muscles
d) tendons
4
Q
True or False:
The muscles of the body ACT DIRECTLY to exert force on the ground or other objects.
A
FALSE.
The muscles of the body function by pulling against bones that rotate about joints which TRANSMITS FORCE TO THE ENVIRONMENT.
5
Q
True or False:
Muscles can only push, not pull.
A
FALSE.
Muscles can only pull. But through the system of bony levers muscle pulling forces can be manifested as either pulling or pushing forces against external objects.
6
Q
Approximately how many bones are in the human body?
A
206
7
Q
Fill in the blanks:
Bones provide a)____________, b)____________ and c)____________.
A
a) leverage
b) support
c) protection
8
Q
Fill in the blanks:
The axial skeleton consists of a)___________, b)___________, c)___________ and d)___________.
A
a) skull (cranium)
b) vertebral column (vertebra C1 through the coccyx)
c) ribs
d) sternum
9
Q
Fill in the blanks:
The appendicular skeleton includes the a)___________, b)___________, c)___________ and d)___________.
A
a) shoulder (or pectoral) girdle (left and right scapula and clavicle)
b) bones of the arms, wrists and hands (left and right humerus, radius, ulna, carpals, metacarpals and phalanges)
c) the pelvic girdle (left and right coxal or innominate bones)
d) bones of the legs, ankles and feet (left and right femur, patella, tibia, fibula, tarsals, metatarsals, and phalanges)
10
Q
Fill in the blank:
Junctions of bones are called _________.
A
Joints.
11
Q
Fill in the blanks:
The 3 types of joints are a)_________, b)_________ and c)_________.
A
a) fibrous
b) cartilaginous
c) synovial
12
Q
Name an example of a fibrous joint and how much movement it allows.
A
Sutures of the skull; allows virtually no movement.
13
Q
Name an example of a cartilaginous joint and how much movement that joint allows.
A
Intervertebral discs; allows limited movement.
14
Q
Name an example of a synovial joint and how much movement that joint allows.
A
Elbow and knee; allows considerable movement.
15
Q
Sport and exercise movements occur mainly about which type of joints?
A
Synovial joints.
16
Q
What are the two most important features of synovial joints.
A
- low friction
2. large range of motion
17
Q
Fill in the blank:
Articulating bone ends in synovial joints are covered with smooth _________.
A
Hyaline cartilage
18
Q
Fill in the blank:
The entire synovial joint is enclosed in a capsule filled with ____________ fluid.
A
Synovial
19
Q
List the 3 categories of joints, the number of axes around which they rotate, and an example of each?
A
- uniaxial; 1 axis; elbow
- biaxial; 2 perpendicular axes; ankle/ wrist
- multiaxial; all 3 perpendicular axes that define space; shoulder and hip ball-and-socket joints.
20
Q
True or False:
The knee is a true uniaxial hinge joint.
A
False.
The knee’s axis of rotation changes throughout the range of motion.
21
Q
Fill in the blanks:
The a) _________ is made up of vertebral bones separated by flexible b) _________ that allow movement to occur.
A
a) vertebral column
b) discs
22
Q
Name the 5 regions of the vertebral column.
A
- cervical
- thoracic
- lumbar
- sacral
- coccygeal
23
Q
List the number of vertebrae in each of the 5 regions of the vertebral column.
- cervical
- thoracic
- lumbar
- sacral
- coccygeal
A
- 7 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral (fused together)
- 3 to 5 coccygeal
24
Q
True or False:
When the body is subjected to heavy loads the bone will increase in density and bone mineral content.
A
True.
25
List factors that can affect skeletal growth in an adult.
1. Frequency of loading the body (how often).
2. Intensity of loading (how heavy).
3. Type of loading (resistance training, explosive movements with impact, high intensity training, etc)
26
True or False:
There are several things that can positively affect the adult skeleton, and most are not a result of muscle use.
False.
Muscle use is one of the major things that positively affects the adult skeleton.
27
What do you call the connection point between bones?
Joint.
28
# Fill in the blanks:
Each skeletal muscle is an organ that contains a)_________ tissue, b)_________ tissue, c)________ and d)_________.
a. muscle tissue
b. connective tissue
c. nerves
d. blood vessels
29
True or False:
Each skeletal muscle is an organ.
True.
30
What is the specialized connective tissue covering all bones?
Periosteum.
key to remembering: osteum means relating to bone.
31
What is the outermost layer of fibrous connective tissue covering the body's more than 430 skeletal muscles?
Epimysium
key to remembering: epi- means upon or above
I remember epi- by thinking "Epi is epic. It's big. It's the outermost layer."
32
True or False:
The epimysium is not contiguous with the tendons at the ends of the muscle.
False.
33
True or False:
Any contraction of a muscle (with a tendon) pulls on the tendon and in turn pulls on the bone.
True.
34
Limb muscles have 2 attachment sites to bone. The names given to these attachment sites describes the relative location of the attachments relative to the trunk. List the 2 names given to this relative location and describe where they are located.
1. proximal attachments: located closer to the trunk
| 2. distal attachments: located farther from the trunk
35
Trunk muscles have 2 attachment sites to bone. The names given to these attachment sites describes the relative location of the attachments relative to the head and feet. List the 2 names given to this relative location and describe where they are located.
1. superior: closer to the head
| 2. inferior: closer to the feet
36
Another name for muscle cells.
Muscle fibers
37
True or False:
A muscle fiber can have a diameter up to about the diameter of a human hair.
True
38
# Fill in the blank:
The epimysium covers groups of bundled muscle fibers called ______________ that may consist of up to 150 fibers.
Fascicles
39
What is the name of the connective tissue that surrounds a fascicle?
Perimysium
key to remembering: peri- means about or around
I remember peri- by thinking "The peri- is around or about the middle."
40
What is the name of the connective tissue that surrounds a muscle fiber?
Endomysium
key to remembering: endo- means 'within'
I remember endo- by thinking "Endo is inside." The deepest layer.
41
What is the membrane of a muscle fiber?
Sarcolemma
key to remembering: sarco- means flesh
-lemma means "to peel"
42
True or False:
All the connective tissue - epimysium, perimysium, and endomysium - is contiguous with the tendon, so tension developed in a muscle cell is transmitted to the tendon and the bone to which it is attached.
True
43
What is a motor neuron?
A motor neuron is a nerve cell.
44
# Fill in the blank:
The junction between a motor neuron and the muscle fibers it innervates is called the ___________.
Neuromuscular junction.
45
True or False:
Each muscle cell can have multiple neuromuscular junctions.
False.
Each muscle cell has only one neuromuscular junction.
46
What is a motor unit?
A motor neuron and the muscle fibers it innervates.
47
True or False:
A single motor neuron innervates many muscle fibers, sometimes hundreds or even thousands.
True.
48
# Fill in the blank:
A motor neuron and the muscle fibers it innervates are called a _________.
motor unit
49
What is the term for the cytoplasm of a muscle fiber that contains contractile components consisting of protein filaments, other proteins, stored glycogen and fat particles, enzymes, and specialized organelles such as mitochondria and the sarcoplasmic reticulum.
sarcoplasm
50
# Fill in the blanks:
Hundreds of a)__________ dominate the sarcoplasm. b)___________ contain the apparatus that contracts the muscle cell, which consists primarily of two types of myofilament: c) _________ and d)________.
a) myofibrils
b) myofibrils
c) myosin
d) actin
51
Name the thick myofilament that contains a globular head, a hinge point, and a fibrous tail.
myosin
52
Name the thin myofilament that consists of two strands arranged in a double helix.
actin
53
# Fill in the blank:
The arrangement of myosin (thick) and actin (thin) filaments gives skeletal muscle its ________ appearance.
striated
54
# Fill in the blank:
The globular heads of the myosin filament protrude away from the filament at regular intervals, and a pair of myosin filaments forms a ___________, which interacts with actin.
cross-bridge
55
Name the smallest contractile unit of skeletal muscle.
sarcomere
56
Define sarcomere.
The smallest contractile unit of skeletal muscle.
57
True or False:
Myosin and actin filaments are organized latitudinally in the sarcomere.
False.
Myosin and actin are organized longitudinally.
58
# Fill in the blank:
Adjacent myosin filaments anchor to each other at the ____________ in the center of the sarcomere (the center of the H zone).
M-Bridge
Key to remember. M is for myosin.
59
What is the M-Bridge?
The center of the sarcomere where adjacent myosin filaments anchor to each other.
60
# Fill in the blank:
Actin filaments are aligned at both ends of the sarcomere and are anchored at the ___________.
Z-line
Key to remember. "Actin' zany!"
61
What is the Z-line?
Where actin filaments anchor at both ends of the sarcomere.
62
Put the correct number in the blank:
______ actin filaments surround each myosin filament, and each actin filament is surrounded by _______ myosin filaments.
6;3
63
True or False:
It is the arrangement of the myosin and actin filaments and the Z-lines of the sarcomeres that gives skeletal muscle its alternating dark and light pattern, which appears striated under magnification.
True
64
# Fill in the blank:
When looking at a detailed view of the myosin and actin filaments in muscle, the dark ________ corresponds with the alignment of the myosin filaments and contains both myosin and actin.
A-band
65
What is the A-band in a muscle?
The dark band that corresponds with the alignment of the myosin filaments in a muscle. The A-band contains both myosin and actin.
66
# Fill in the blank:
When looking at a detailed view of the myosin and actin filaments in muscle, the light ________ corresponds with the areas in two adjacent sarcomeres that contain only actin filaments.
I-band (only actin)
Key to remembering: "I stand alone." And associate actin as the outsider waiting to be pulled in by the myosin protein.
67
# Fill in the blank:
The _______ is the area in the center of the sarcomere where only myosin filaments are present.
H-zone (only myosin)
68
True or False:
During muscle contraction, the H-zone decreases as the actin slides over the myosin towards the center of the sarcomere.
True.
69
# Fill in the blank:
Parallel to and surrounding each myofibril is an intricate system of tubules, called _______________, which terminates as vesicles in the vicinity of Z-lines. Calcium ions are stored in the vesicles.
sarcoplasmic reticulum
70
True or False:
The regulation of calcium controls muscular contraction.
True
71
What controls muscular contraction?
The regulation of calcium.
72
What is an action potential?
An electrical nerve impulse.
73
What is the term for an electrical nerve impulse?
Action potential
74
# Fill in the blank:
The discharge of an ____________ from a motor nerve signals the release of calcium from the sarcoplasmic reticulum into the myofibril causing tension development in muscle.
Action potential
75
# Fill in the blanks:
The sliding-filament theory states that the a) _________ filaments at each end of the sarcomere slide inward on b)________ filaments, pulling the c)__________ toward the center of the sarcomere and thus shortening the muscle fiber.
a) acitn
b) myosin
c) Z-lines
76
True or False:
As acting filaments slide over myosin filaments, the H-zone shrinks while the I-band lengthens.
False
Both the H-zone and I-band shrink.
77
# Fill in the blanks:
The action of a)___________ crossbridges pulling on the b)________ filaments is responsible for the movement of the c) _________ filament.
a) myosin
b) actin
c) actin
78
In what phase of the sliding-filament theory of muscular contraction is there very little calcium present in the myofibril where most of the calcium is stored in the sarcoplasmic reticulum so very few of the myosin crossbridges are bound to actin?
Resting phase
79
True or False:
The actin binding site is exposed after release of the stored calcium.
True
80
When the sarcoplasmic reticulum is stimulated to release calcium ions, the calcium binds to what protein that is situated at regular intervals along the actin filament and has a high affinity for calcium ions?
Troponin
81
When calcium ions bind to troponin, this causes a shift to what other protein which runs along the length of the actin filament in the groove of the double helix?
Tropomyosin
82
True or False:
The number of crossbridges that are formed between actin and myosin at any instant in time dictates the force production of a muscle.
True
83
# Fill in the blanks:
Once the sarcoplasmic reticulum is stimulated to release calcium ions that bind to troponin which in turn causes a shift to the protein tropomyosin the a)_____________ now attaches much more rapidly to the b) ____________ filament which allows force to be produced as the
c) ________ filaments are pulled toward the center of the d) ________.
a) myosin crossbridge
b) actin
c) actin
d) sarcomere
84
EXTRA CREDIT: List 4 steps of the Excitation-Contraction Coupling Phase.
1. sarcoplasmic reticulum is stimulated to release calcium ions
2. calcium ions binds with the protein troponin that is situated at regular intervals along the actin filament.
3. tropomyosin, which runs the length of the actin filament in the groove of the double helix, shifts
4. the myosin crossbridge now attaches rapidly to the actin filament
85
Define 'power stroke.'
Power stroke is the energy for pulling action of the myosin crossbridge on the actin filament.
86
What must occur in the contraction phase according to the sliding-filament theory of muscle contraction. What happens chemically?
The energy for the power stroke comes from: the hydrolysis (breakdown) of ATP to ADP and phosphate, a reaction catalyzed by the enzyme myosin adenosine triphosphatase (ATPase).
ATP must be broken down to ADP to begin the contraction.
87
What must occur in order for the muscle fiber to go back to it's resting length?
Another molecule of ATP must replace the ADP on the myosin crossbridge globular head in order for the head to detach from the active actin site.
ATP must be present in order to relax the muscle.
88
# Fill in the blanks:
a)_________ and b)___________ are necessary for crossbridge cycling with c)_________ and d)________ filaments.
a) Calcium
b) ATP
c) actin
d) myosin
89
List the 5 steps (on a molecular level) of muscle contraction.
1. initiation of ATP splitting (by myosin ATPase) causes myosin head to be in an energized state
2. release of phosphate from the ATP splitting process causes the myosin head to change shape and shift
3. the actin filament is pulled toward the center of the sarcomere. ADP is released.
4. Once ADP released the myosin head detaches from the actin but only after another ATP binds to the myosin head to facilitate detachment
5. myosin head is read to bind to another actin
90
The cycle of muscle contraction continues so long as a)________ and b)_______ are present and c)__________ is bound to the d)________.
a) ATP
b) ATPase
c) calcium
d) troponin
91
What are the names of the 5 phases of muscle contraction?
1. resting phase
2. excitation-contraction coupling phase
3. contraction phase
4. recharge phase
5. relaxation phase
92
True or False:
The relaxation phase of muscle contraction is brought about by the return of the actin and myosin filaments to their unbound state once calcium is pumped back into the sarcoplasmic reticulum which prevents the link between the actin and myosin filaments.
True.
93
# Fill in the blanks:
Muscle fibers are innervated by a) ________________ that transmit impulses in the form of b)_____________ signals from the spinal cord to muscle.
a) motor neurons
| b) electrochemical
94
True or False:
A motor neuron generally has one terminal branch at the end of its axon and innervates only one muscle fiber.
False:
A motor neuron has numerous terminal branches at the end of its axon and innervates many different muscle fibers.
95
True or False:
The extent of control of a muscle depends on the number of muscle fibers within each motor unit.
True
96
# Fill in the blank:
When a motor neuron fires an impulse or _____________, all of that fibers that it serves are simultaneously activated and develop force.
action potential
97
# Fill in the blank: Less or More
The extent of control of a muscle depends on the number of fibers with each motor unit.
Muscles that function with great precision, such as eye muscles have _________ muscle fibers per motor neuron than muscles that function with less precision such as the quadriceps muscle group.
Less
98
True or False:
Muscles that function with great precision, such as the eye, may have motor units with as few as one muscle fiber per motor neuron.
True.
99
Another way of referring to 'action potential.'
electric current
100
True or False:
The action potential (electric current) that flows along a motor neuron is capable of directly exciting muscle fibers.
False:
The action potential is not capable of directly exciting muscle fibers. The motor neuron excites the muscle fibers it innervates by chemical transmission of a neurotransmitter, acetylcholine.
101
# Fill in the blanks:
The neurotransmitter, a)_____________ diffuses across the b)______________ causing the excitation of the sarcolemma (the membrane of the muscle fiber).
a) acetylcholine
| b) neuromuscular junction
102
Define the all-or-none principle.
All of the muscle fibers in the motor unit contract and develop force at the same time. A stronger action potential (nerve impulse) cannot produce a stronger contraction.
103
# Fill in the blank:
The action potential traveling down a motor neuron results in a short period of activation of the muscle fibers within a motor unit. The brief contraction is called a __________.
twitch
104
True or False:
If a second twitch is elicited from the motor nerve before the fibers completely relax, force from the two twitches summates, and the resulting force is less than that produced by a single twitch.
False.
The resulting force is greater. Decreasing the time interval between twitches results in greater summation of crossbridge binding and force.
105
# Fill in the blank:
When the frequency of muscle fiber twitches is so high, the twitches begin to merge and eventually completely fuse, a condition called __________. This is the maximal amount of force the motor unit can develop.
tetanus
106
True or False:
A motor unit can be composed of muscle fibers of different types (Type I, Type IIa, etc).
False.
A motor unit is only composed of muscle fibers of the same type.
107
# Fill in the blanks:
A fast-twitch motor unit is one that develops force and also relaxes rapidly and thus has a a)_________ twitch time.
Slow-twitch motor units develop force and relax slowly and have a b)________ twitch time.
a) short
| b) long
108
Muscle fiber types can be classified by determining the amount of myosin a)__________ activity or the amount of b)__________ protein.
a) ATPase
| b) Myosin Heavy Chain (MHC)
109
The mechanical characteristics of Type I muscle fibers include:
I. More efficient
II. fatigue resistant
III. have a high capacity for aerobic energy supply
IV. have rapid force development
a. I, II & IV
b. I, II & III
c. I, III & IV
d. all of the above
b.
Type I muscle fibers do not have rapid force development. They are slower than Type II.
110
True or False:
Type I muscle fibers contain low myosin ATPase activity and high anaerobic power.
False:
Type I muscle fibers contain both low myosin ATPase (enzyme) activity and low anaerobic (without oxygen) power.
111
```
The mechanical characteristics of Type II muscle fibers include:
I. inefficient
II. fatigue resistant
III. low aerobic power
IV. have rapid force development
```
a. I, II & IV
b. I, II & III
c. I, III & IV
d. all of the above
c.
Type II muscle fibers fatigue quickly. They produce a lot of power quickly so they run out of gas sooner.
112
True or False:
Type IIx fibers have greater capacity for aerobic metabolism and more capillaries surrounding them Type IIa and also show greater resistance to fatigue.
False:
Type IIa fibers have greater capacity for aerobic metabolism and show greater resistance to fatigue.
key to remembering: think of the 'a' in IIa as meaning aerobic.
113
# Fill in the blanks:
The force output of a muscle can be varied through change in the a)________________ or change in the b)__________.
a) frequency of activation of individual motor units
| b) number of activated motor units
114
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
100m sprint
Type I -- Low
| Type II -- High
115
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
800m run
Type I -- High
| Type II -- High
116
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Marathon
Type I -- High
| Type II -- Low
117
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Olympic Weightlifting
Type I -- Low
| Type II -- High
118
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Soccer, lacrosse, hockey
Type I -- High
| Type II -- High
119
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
American Football Wide Receiver
Type I -- Low
| Type II -- High
120
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
American Football Lineman
Type I -- Low
| Type II -- High
121
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Basketball, team handball
Type I -- Low
| Type II -- High
122
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Volleyball
Type I -- Low
| Type II -- High
123
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Baseball or softball pitcher
Type I -- Low
| Type II -- High
124
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Boxing
Type I -- High
| Type II -- High
125
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Wrestling
Type I -- High
| Type II -- High
126
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
50m swim
Type I -- Low
| Type II -- High
127
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Field Events
Type I -- Low
| Type II -- High
128
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Cross-country skiing, biathlon
Type I -- High
| Type II -- Low
129
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Tennis
Type I -- High
| Type II -- High
130
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Downhill or slalom skiing
Type I -- High
| Type II -- High
131
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Speed skating
Type I -- High
| Type II -- High
132
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Track cycling
Type I -- Low
| Type II -- High
133
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Distance cycling
Type I -- High
| Type II -- Low
134
Relative Involvement of Type I & Type II Muscle Fiber Types in Sport Events (list which muscle fibers are high and which are low)
Rowing
Type I -- High
| Type II -- High
135
# Fill in the blank:
____________ are specialized sensory receptors that provide the central nervous system with information needed to maintain muscle tone and perform complex coordinated movements.
Proprioceptors
136
True or False:
Proprioceptors are not sensitive to pressure and tension.
False.
137
True or False:
Proprioceptors relay information concerning muscle dynamics to the conscious and subconscious parts of the CNS wherein the brain is provided with information concerning kinesthetic sense of the position of body parts with respect to gravity.
Very true!
138
What kind of proprioceptors are modified muscle fibers the provide information concerning muscle length and rate of change in length which through deformation results in greater activation of muscle?
Muscle spindles
139
In what kind of muscle fibers does one find muscle spindles?
Intrafusal
140
The knee jerk reflex is an example of what kind of muscle activity?
Muscle spindle
141
Briefly describe how a muscle spindle works.
When a muscle is stretched...
a) deformation of the muscle spindle activates the sensory neuron via the intrafusal fiber
b) which sends the impulse to the spinal cord where
c) it synapses with a motor neuron
d) causing the muscle to contract
142
How can an athlete improve force production. List 3 ways.
1. Increase heavier loads in order to optimize neural recruitment
2. increase the cross-sectional area of muscles involved in the desired activity
3. perform multimuscle, multijoint exercises that can be done with more explosive actions to optimize fast-twitch muscle recruitment.
143
What type of proprioceptors are located in tendons near the myotendinous junction and are in series (attached end to end) with extrafusal muscle fibers?
Golgi Tendon Organs (GTOs)
144
True or False:
GTOs facilitate activation of the muscle.
False:
GTOs inhibit muscle activation (relaxes the muscle)
145
Briefly describe how a Golgi tendon organ works.
When an extremely heavy load is placed on the muscle...
a) discharge of the GTO occurs (from the tendon)
b) the sensor neuron of the GTO activates an inhibitory interneuron in the spinal cord
c) which in turn synapses with and inhibits a motor neuron serving the same muscle
146
True or False:
The effect of GTOs is minimal at low forces; but when an extremely heavy load is placed on the muscle, reflexive inhibition mediated by the GTOs causes the muscle to relax.
True
147
What type of training can cause a fundamental adaptation of the motor cortex to be able to override the inhibition caused by GTOs?
Heavy resistance training.
It takes a heavy load to kick in the GTOs response.
148
List 3 primary roles of the cardiovascular system.
1. transport nutrients
2. remove waste and by-products
3. assist with maintaining the environment for all the body's functions
149
True or False:
The cardiovascular system does not play a key role in the regulation of the body's acid-base system, fluids, and temperature.
False
It most certainly does.
150
# Fill in the blanks: Right or Left
The _________ side of the heart pumps blood through the lungs and the ________ side pumps blood through the rest of the body.
right; left
Key to remember: blood pumps RIGHT to the lungs and what's LEFT over goes to the rest of the body.
151
True or False:
The heart is a muscular organ composed of one pump.
False
The heart is composed of two interconnected but separate pumps: the right and the left.
152
# Fill in the blanks:
Each pump of the heart as an a)___________ and a b)__________. The right and left c)_________ deliver blood into the right and left d)________. The right and left e)__________ supply the main force for moving blood through pulmonary and peripheral circulations, respectively.
a) atrium
b) ventricle
c) atria
d) ventricles
e) ventricles
153
Which ventricle delivers blood to the lungs?
the right ventricle
154
Which ventricle delivers blood to the rest of the body (but not the lungs)?
the left ventricle
155
What is the term for ventricular contraction?
systole
156
What is the term for ventricular relaxation?
diastole
157
# Fill in the blank:
The tricuspid valve and mitral valves of the heart are collectively called ___________.
atrioventricular valves (AV)
158
# Fill in the blanks:
The AV valves prevent the flow of blood from the a)__________ back into the b)_________ during ventricular contraction.
a) ventricles
| b) atria
159
What are the two semilunar valves of the heart?
aortic valve; pulmonary valve
160
What do the semilunar valves of the heart do?
Prevent backflow from the aorta and pulmonary arteries into the ventricles during ventricular relaxation.
161
True or False:
The valves of the heart opens and closes actively (ie through muscular contraction).
False
The valves of the heart (the AV and semilunar valves) open and close passively. Each closes when backward pressure gradient pushes blood back against it and opens when a forward pressure gradient forces the blood in the forward direction.
162
List the 6 components of the electrical conduction system of the heart
1. sinoatrial (SA) node -- the intrinsic pacemaker where electrical impulses are initiated
2. the internodal pathways that conduct the impulse from the SA node to the AV node
3. atrioventricular (AV) node where the impulse is delayed slightly before passing into the ventricles
4. atrioventricular (AV) bundle which conducts the impulse to the ventricles
5. the left bundle branch and right bundle branch which futher divide into
6. the Purkinje fibers that conduct impulses to all parts of the ventricles
163
Briefly describe the conduction system of the heart by listing the pathways of the electric current.
The electric impulses are initated by the pacemaker or the SA (sinoatrial) node.
The internodal pathways conduct the impulse from the SA node to the AV (atrioventricular) node
The AV node is where the impulse is delayed slightly before passing into the ventricles
The AV bundle conducts the impulse to the ventricles
Where the left bundle branch and right bundle branch further divide into
the Purkinje fibers that conduct impulses to all parts of the ventricles.
164
What is the intrinsic pacemaker of the heart?
sinoatrial (SA) node
165
In what part of the heart is the electrical impulse briefly delayed before passing into the ventricles?
atrioventricular (AV) node
166
Which part of the heart's conduction system conducts the impulse to the ventricles?
atrioventricular (AV) bundle
167
Which fibers conduct impulses to all parts of the ventricles once the impulse travel through the left and right bundle branches of the AV bundle?
Purkinje fibers
168
What is the term for 'heart muscle?'
myocardium
myo- means muscle
cardium means heart
169
# Fill in the blank: sympathetic or parasympathetic?
The atria of the heart are supplied with a large number of both sympathetic and parasympathetic neurons, whereas the ventricles receive _____________ fibers almost exclusively.
sympathetic
key to remembering: parasympathetic is 'rest and digest' mode where as sympathetic is 'get up and go, fight or flight.' Most people want their ventricles to keep on pumping, to keep on getting up and going.
170
# Fill in the blank: bradycardia or tachycardia
The resting heart rate normally ranges from 60 to 80 beats/min; fewer than 60 beats/ min is called a)__________ and more than 100 beats/min is called b)__________.
a) bradycardia
| b) tachycardia
171
What is the term for a graphic representation of the activity of the heart that is recorded at the surface of the body?
electrocardiogram ECG
172
# Fill in the blank:
The P-wave in an ECG is a recording of ____________ contraction.
atrial
173
# Fill in the blank:
The QRS complex in an ECG is a recording of ____________ contraction.
ventricular
174
# Fill in the blank:
The T-wave in an ECG is a recording of ____________ relaxation.
ventricular
key to remember how to read ECG: the waves occur in alphabetical order beginning with P and ending at T. Blood enters first to the atrium, the atrium contracts (P-wave) and pushes the blood into the ventricles which in turn contract (QRS complex) and pump the blood out to the lungs and the rest of the body. After the blood is pumped out of the ventricles there is a period of ventricular relaxation during which the ventricles fill up with blood again (T-wave).
175
Electrocardiogram: Define depolarization
The reversal of the membrane electrical potential whereby the normally negative potential inside the membrane becomes slightly positive and the outside becomes slightly negative resulting on a contraction.
Depolarization leads to contraction.
176
Electrocardiogram: Define repolarization
Recovering from the state of depolarization .
Repolarization leads to a temporary relaxation.
177
The part of the closed-circuit circulatory system that carries blood away from the heart.
arterial system
178
The part of the closed-circuit circulatory system that returns blood toward from the heart.
venous system
179
What is the function of arteries?
To rapidly transport blood pumped from the heart.
180
What is the term for the small branches of arteries that act as control vessels through which blood enters the capillaries?
arterioles
181
True or False
Arteries have relatively weak walls.
False
Arteries have strong muscular walls due to the blood being pumped from the heart at high pressure.
182
True or False
Arterioles have strong, muscular walls that are capable of closing the arteriole completely or allowing it to be dilated many times their size, thus vastly altering blood flow to the capillaries in response to the needs of the tissues.
True
183
What is the function of capillaries?
To facilitate exchange of oxygen, fluid, nutrients, electrolytes, hormones and other substances between the blood and the interstitial fluid in the various tissues of the body.
184
True or False
The capillary walls are very strong and impermeable.
False
Capillary walls are very thin and permeable.
185
# Fill in the blank:
__________ collect blood from the capillaries and gradually converge into veins.
Venules
186
True or False:
Pressure in the venous system is very high.
False.
Pressure is very low which makes the vein walls thin although muscular.
187
True or False:
Pressure in the venous system is very low but the venous walls are thin and muscular which allows them to constrict or dilate to a great degree and act as a reservoir for blood.
True
188
True or False:
Veins in the legs contain one-way valves that help maintain venous return by preventing retrograde blood flow.
True
189
# Fill in the blanks:
The cardiovascular system transports a)_________ and removes b)______________ while helping to maintain the environment for all the body's functions.
a) nutrients
| b) waste products
190
# Fill in the blanks:
The a)__________ transports b)__________ from the lungs to the tissues for use in cellular c)_______________; and it transports d)_______________ from the tissues to the e)_________ where it is removed from the body.
a) blood
b) oxygen
c) metabolism
d) carbon dioxide
e) lungs
191
The two paramount functions of blood are:
1. the transport of oxygen from the lungs to the tissues for use in cellular metabolism
2. the removal of carbon dioxide (the most abdundant by-product of metabolism) from the tissues to the lungs.
192
What is hemoglobin and what does it do?
hemoglobin is the iron-protein molecule carried by red blood cells that transports oxygen and also is an acid-base buffer which regulates hydrogen ion concentration which is crucial to the rates of chemical reactions in cells.
193
Name the iron-protein molecule carried by the red blood cells with the following functions:
a. transports oxygen
b. acid-base buffer
c. regulates hydrogen ion concentration
hemoglobin
194
What is the major component of blood?
Red blood cells
195
Name a key function of red blood cells.
Red blood cells catalyze the reaction between carbon dioxide and water to facilitate carbon dioxide removal.
196
# Fill in the blank:
The _________________ is the assistance that contracting muscles provide to the circulatory system that works with the venous system by compressing the veins helping to send blood back to the heart.
skeletal muscle pump
197
Name the mechanism that is one of the reasons that people are told to keep moving around after exercise to avoid blood pooling in the lower extremities as well as the reason why it is recommended to periodically squeeze muscles during prolonged sitting to facilitate blood return to the heart.
skeletal muscle pump
198
What is the primary function of the respiratory system?
The basic exchange of oxygen and carbon dioxide.
199
What 3 functions do the nasal cavities perform as air passes through the nose?
1. warming the air
2. humidifying the air
3. purifying the air
200
Air is distributed to the lungs by way of what 3 passages?
1. trachea
2. bronchi
3. bronchioles
201
What is the name of the first-generation respiratory passage?
trachea
202
What is the name of the second-generation respiratory passage?
the right and left bronchi
203
Where in the lungs does the air finally reach where gases are exchanged in respiration?
alveoli
204
About how many generations of respiratory passages are there before air finally makes it to the alveoli?
23
205
# Fill in the blanks:
The amount and movement of air and expired gases in and out of the lungs are controlled by a)__________ and b)____________ of the lungs.
a) expansion
| b) recoil
206
True or False
The lungs actively expand and recoil themselves.
False.
The lungs do not. They are acted upon to do so in 2 ways:
1. the downward and upward movement of the diaphragm to lengthen and shorten the chest cavity
2. the elevation and depression of the ribs to increase and decrease the back-to-front diameter of the chest cavity
207
Name the 2 actions that allow for the expansion and recoil of the lungs during respiration.
1. the downward and upward movement of the diaphragm to lengthen and shorten the chest cavity
2. the elevation and depression of the ribs to increase and decrease the back-to-front diameter of the chest cavity
208
# Fill in the blank:
Normal, quiet breathing is accomplished almost entirely by movement of the __________.
diaphragm
209
# Fill in the blanks:
During inspiration, contraction of the a)__________ creates a b)______________ pressure or a c)_________ in the chest cavity, and air is drawn into the d)_______.
a) diaphragm
b) negative
c) vacuum
d) lungs
210
True or False:
Normal, quiet breathing is accomplished almost entirely by non-movement of the diaphragm.
False.
211
# Fill in the blanks:
During normal expiration, the a)_____________ simply b)____________; the elastic recoil of the lungs, chest wall and abdominal structures compresses the lungs and air is c)_________.
a) diaphragm
b) relaxes
c) expelled
212
True or False:
During heavy breathing, the elastic force of the lungs, chest wall and abdominal structures are not powerful enough to provide the necessary respiratory response.
True
213
# Fill in the blanks:
During heavy breathing, the extra required force needed for expiration is achieved mainly by contraction of the a)___________ which push the b)__________ upward against the bottom of the c)____________.
a) abdominal muscles
b) abdomen
c) diaphragm
214
# Fill in the blank:
The muscles that elevate the rib cage are called muscles of ___________.
inspiration
215
The external intercostals, the sternocleidomastoids, the anterior serrati, and the scaleni are examples of muscles of ___________.
inspiration
216
Name 4 muscles of inspiration.
1. external intercostals
2. sternocleidomastoids (SCM)
3. anterior serrati
4. scaleni
217
Describe what happens to the ribs, chest and sternum during inspiration.
The rib cage elevates and allows the ribs to project almost directly forward so the sternum can move forward away from the spine. Upward and outward movement of the ribs.
218
# Fill in the blank:
The muscles that depress the chest are muscles of __________.
expiration
219
Name 5 muscles of expiration. Hint 4 are part of the abdominal group.
1. rectus abdominis
2. external obliques
3. internal obliques
4. transversus abdominis
5. internal intercostals
220
Define pleura.
The membranes enveloping the lungs and lining the chest walls.
221
# Fill in the blank:
_____________ are the membranes enveloping the lungs and lining the chest walls.
Pleura
222
Define pleural pressure.
The pressure in the narrow space between the lung pleura and the chest wall pleura.
223
# Fill in the blank:
The pressure in the narrow space between the lung pleura and the chest wall pleura is called ___________.
Pleural pressure.
224
# Fill in the blank: positive or negative
Pleural pressure is normally slightly _________.
negative
225
True or False:
Because the lung is elastic, during normal inspiration the expansion of the chest cage is able to pull on the surface of the lungs and creates a more negative pressure, thus enhancing inspiration.
True
226
What kind of pressure is the pressure inside the alveoli when the glottis is open and no air is flowing into or out of the lungs?
Alveolar
227
# Fill in the blank:
To cause inward flow of air during inspiration, the pressure in the alveoli must fall to a value slight below _________________.
atmospheric pressure
228
# Fill in the blank:
During expiration, alveolar pressure must rise ___________ atmospheric pressure.
above
229
The total energy expended by the body required for pulmonary ventilation.
3% - 5%
230
During heavy exercise, the amount of energy required for pulmonary ventilation.
8% - 15%
231
Define diffusion.
With ventilation, the process by which oxygen diffuses from the alveoli into the pulmonary blood, and carbon dioxide diffuses from the blood into the alveoli.
232
# Fill in the blank:
Oxygen diffuses from the a)_________ into the b)__________.
a) alveoli
| b) pulmonary blood
233
# Fill in the blank:
Carbon dioxide diffuses from the a)_________ into the b)__________.
a) blood
| b) alveoli
234
True or False:
Regular exercise in general is beneficial for maintaining respiratory muscle function.
True
235
True or False:
It is generally not necessary to specifically train the muscles of respiration except following surgery or during prolonged bed rest when the normal breathing patterns are compromise.
True
236
True or False:
Endurance exercise taxes the diaphragm and abdominal muscles especially because of their use for stabilization and for increasing intra-abdominal pressure during exertion.
False
Resistance exercise taxes the diaphragm and abdominal muscles.
237
True or False
Resistance exercise typically involves repetitive contraction of breathing muscles more so than the taxing of the diaphragm and abdominal muscles.
False.
Endurance exercise typically involves more repetitive contraction of the breathing muscles than the taxing of diaphragm and abdominal muscles.
238
Which of the following substances regulates muscle actions?
a. potassium
b. calcium
c. troponin
d. tropomyosin
b. calcium
239
Which of the following substances acts at the neuromuscular junction to excite the muscle fibers of a motor unit?
a. acetylcholine
b. ATP
c. creatine phosphate
d. serotonin
a. acetylcholine
240
When throwing a baseball, an athlete's arm is rapidly stretched just before throwing the ball. Which of the following structures detects and responds to that stretch by reflexively increasing muscle activity?
a. Golgi tendon organ
b. muscle spindle
c. extrafusal muscle
d. Pacinian corpuscle
b. muscle spindle
241
From which of the following is the heart's electrical impulse normally initiated?
a. AV node
b. SA node
c. the brain
d. the sympathetic nervous system
b. SA node
242
```
Which of the following occurs during the QRS complex of a typical ECG?
I. depolarization of the atrium
II. repolarization of the atrium
III. repolarization of the ventricle
IV. depolarization of the ventricle
a. I and III only
b. II and IV only
c. I, II and III only
d. II, III and IV only
```
b. II and IV only
