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Chapter 11: The Cardiovascular System
Worksheet Answers
Exercise 1.
True-False. Indicate whether each of the following statements is true or false by circling
+ if true and O if false. If the statement is false correct it in the space provided.
+
O
1. Cells in each area of the myocardial conduction system have their own rate;
the inherent rhythm of the AV node determines a healthy individual’s
resting heart rate.
The inherent rhythm of the SA node determines a healthy individual’s
resting heart rate.
+
O
2. The events diagrammed in the electrocardiogram (ECG) precede contraction
of the respective atrial and ventricular myocardial cells.
+
O
3. Stroke volume increases during exercise because of an increase in enddiastolic ventricular volume and an increase in end-systolic ventricular
volume.
Stroke volume increases because of an increase in end-diastolic
ventricular volume and/or a decrease in end-systolic volume.
+
O
4. During exercise the Frank-Starling mechanism (increased preload ) and
increased contractility due to sympathetic nervous stimulation ) function
together to enhance stroke volume.
+
O
5. Myocardial oxygen consumption can be estimated by the rate-pressure
product, which is the product of HR x DBP.
Plowman & Smith: Exercise Physiology for Health, Fitness, and Performance, 4th ed. ©Lippincott
Williams & Wilkins, 2014
Page 1
The rate–pressure product is the product of SBP × HR.
+
O
6. The opening and closing of the AV valves and semilunar valves are
controlled by smooth muscle contraction.
Pressure differences control the opening and closing of the AV and
semilunar valves.
+
O
7. The major hormones involved in maintaining blood volume are antidiuretic
hormone (ADH) and aldosterone.
+
O
8. The velocity of blood flow is greatest (fastest) in the capillaries because the
capillaries have the greatest total cross-sectional area.
Velocity is the least (slowest) in the capillaries because they have the
highest total cross-sectional area.
+
O
9. Sympathetic stimulation increases the rate and force of heart contraction.
+
O 10. Under resting conditions, the heart ejects approximately 70-80% of the blood
contained in the ventricles.
Under resting conditions, the heart ejects ~50–60% of the
blood contained in the ventricles.
+
O 11. Under resting conditions, 40-50% of the available oxygen is extracted as
blood flows through the coronary circulation.
Under resting conditions, 60–70% of the available oxygen is extracted
as blood flows through the coronary circulation.
+
O
12. Increased myocardial oxygen consumption is supported by increased blood
flow to the myocardium, which, in turn, is achieved by increased
myocardial contraction and arteriole vasodilation due to increased cellular
Plowman & Smith: Exercise Physiology for Health, Fitness, and Performance, 4th ed. ©Lippincott
Williams & Wilkins, 2014
Page 2
by-products.
+
O 13. Mean arterial blood pressure at rest is not simply calculated as the average
of SBP and DBP because diastole lasts longer than systole and must be
weighted more heavily.
+
O
14. Strenuous activity should be avoided for approximately 24 hr after donating
one pint of blood, and training intensity should not be increased for
approximately 6 weeks.
+
O
15. Air flow and blood flow occur when the pressure gradient is less than the
resistance opposing the flow.
Air flow and blood flow occur when the pressure gradient is greater
than the resistance opposing the flow.
+
O
16. Most ventricular filling occurs passively when both the atria and ventricles
are in diastole and the AV valves are open with some assistance from
gravity in an upright individual. Atrial contraction pushes only a small
additional amount of blood into the ventricles.
+
O
17. Stroke volume increases as afterload increases.
Stroke volume decreases as afterload increases.
+
O
18. At rest, the entire volume of blood is circulated through the body each
minute.
+
O
19. The Fifth Korotkoff Sound (DBP2 = disappearance) is considered the most
accurate measurement of diastolic blood pressure in normal adults at rest.
However, the Fourth Korotkoff Sound (DBP1 = muffling) is
recommended for children, adults during exercise, and adults if DBP2
Plowman & Smith: Exercise Physiology for Health, Fitness, and Performance, 4th ed. ©Lippincott
Williams & Wilkins, 2014
Page 3
is less than 40 mmHg.
+
O 20. The primary difference between cardiac and skeletal muscle cells is that
adjacent cardiac cells (but not adjacent skeletal muscle cells) are structurally
linked by intercalated discs containing gap junctions allowing electrical
activity in one cell to pass to the next.
+
O 21. It is possible to improve one’s cardiovascular function whenever heart rate is
elevated whether by heat, emotion, or exercise.
It is possible to improve one’s cardiovascular function only when heart
rate is elevated by exercise because then the elevated HR reflects an
increased energy expenditure.
+
O 22. Central cardiovascular responses are those occurring in blood vessels
(vasodilation, vasoconstriction, venous return, etc) whereas peripheral
cardiovascular responses are directly related to the heart (heart rate, stroke
volume, cardiac output, etc.).
Peripheral cardiovascular responses are those occurring in blood vessels
(vasodilation, vasoconstriction, venous return, etc.) whereas central
cardiovascular responses are directly related to the heart (heart rate,
stroke volume, cardiac output, etc.).
Plowman & Smith: Exercise Physiology for Health, Fitness, and Performance, 4th ed. ©Lippincott
Williams & Wilkins, 2014
Page 4
Exercise 2.
Calculations. Given the information provided, perform the following calculations for
the individual (Caitlin) described. Be sure to provide units for each variable.
1. SV = EDV − ESV
SV = 160 mL − 50 mL = 110 mL
2. EF = (SV/EDV) × 100
EF = (110 mL ÷ 160 mL) × 100 = 68.75%
3. Q = SV × HR
Q = 110 mL × 120 b min−1 = 13,200 mL min−1 = 13.2 L min−1
4. MAP = PP ÷ 2 + DBP1 (PP = SBP − DBP1)
MAP = [ (130 mmHg − 70 mmHg) ÷ 2 ] + 70 mmHg = 100 mmHg
5. RPP = (HR × SBP) / 100
RPP = (120 b min−1 × 130 mmHg) ÷100 = 156 units
6. TPR = MAP/Q
TPR = 100 mm HG ÷ 13.2 L min−1 = 7.58 (TPR units)
Plowman & Smith: Exercise Physiology for Health, Fitness, and Performance, 4th ed. ©Lippincott
Williams & Wilkins, 2014
Page 5
Exercise 3.
Matching. A) Match the myocardial electrical event with the electrocardial wave or
complex.
__A__ Atrial depolarization
__C__ Atrial repolarization
__B__ Ventricular depolarization
__D__ Ventricular repolarization
A. P wave
B. QRS complex
C. Ta wave
D. T wave
B) Match the equation/formula in Column I with the variable being calculated in Column
II and the unit of measurement in Column III. Some of the variables and units may be
used more than once.
Column I: Equation/Formula
__B/ M__ (SV ÷ EDV) × 100
__G/ J__ EDV – ESV
__A/ I__ SV × HR
__F/ N__ (SBP × HR) ÷ 100
__E/ L__ (PP ÷ 3) + DBP2
__D, L__ (PP ÷ 2) + DBP1
Plowman & Smith: Exercise Physiology for Health, Fitness, and Performance, 4th ed. ©Lippincott
Williams & Wilkins, 2014
Page 6
__A/ I__ MAP ÷ TPR
.
__A/ I__ VO 2 ÷ a – v O2 diff
__C/ K__ [Qmax × (a – v O2 diff)max] ÷ BW
__H/ N__ MAP ÷ Q
Column II: Variable
A. Cardiac output
B. Ejection fraction (EF)
.
C. Maximal oxygen consumption ( VO 2 max)
D. Mean arterial pressure (exercise)
E. Mean arterial pressure (rest and recovery)
F. Rate pressure product
G. Stroke volume
H. Total peripheral resistance
Column III: Unit of Measurement
I. L∙min-1
J. mL∙b-1
K. mL∙kg.min-1
L. mmHg
M. Percentage (%)
N. Unit
Plowman & Smith: Exercise Physiology for Health, Fitness, and Performance, 4th ed. ©Lippincott
Williams & Wilkins, 2014
Page 7