Ch 6: Cardiovascular System
What is the MAP if the Systolic BP is 120 and Diastolic is 80?
93 mm Hg
An individual has an exercise blood pressure of 150/70 mmHg, a heart rate of 140 b min−1, O2 consumption of 33 mL kg−1 min−1 and a stroke volume of 95 mL beat−1. What is his mean arterial blood pressure?
96.4 mmHg
Autorhythmicity is the ability for the heart to initiate its own
impulse for contraction
The sinoatrial (SA) node is located
in the right atria
If end-diastolic volume increase and end-systolic volume remains constant, stroke volume will _______________.
increase
An increase in venous return will results in a(n)
increase in EDV
During exercise, an increase in Q, vasodilation within active tissue, and vasoconstriction within inactive tissue results in a(n)
increase of blood flow and oxygen delivery to inactive muscle
The increase in stroke volume (SV) as the result of endurance training is not due to which of the following?
increased HRmax
Which of the following is not a component of the cardiovascular system?
Lungs
Oxygen and carbon dioxide exchange occur in the pulmonary circuit only.
false
The heart extracts oxygen and nutrients from the peripheral circulation.
false
The major arteries and veins of the heart are located on the inner surface of the heart.
false
The aortic semilunar valve allows blood to flow
from the left ventricle into the aorta
All of the following are factors that can change the resistance to flow except
heart rate
Stimulation of parasympathetic nerve fibers cause a decrease in
heart rate
The ratio of blood cells to total blood volume, expressed as a percentage, is the
hematocrit
Electrical activity in the heart originates in the ____________ (also known as the "pacemaker").
Sinoatrial (SA) node
The Frank-Starling mechanism is explained by the relationship of what two features of the ventricular muscle?
length; tension
The relationship between heart rate and peak oxygen consumption can be described as
linear
Peripheral venous blood and pulmonary arterial blood is _____ in oxygen and _____ in carbon dioxide content.
low; high
Typical Cardiac output (Q)
men: 5 L min−1 women: 4.5 L min−1
To increase heart rate, the sympathetic fibers release
norepinephrine
Parasympathetic nerve fibers at the SA and AV nodes release the neurotransmitter __________________, which results in decreased heart rate, whereas the sympathetic nerve fibers release _________________, which results in an increased heart rate.
norepinephrine, acetylcholine
During dynamic aerobic exercise, blood is
shunted from the gastrointestinal (GI) tract
If the resting cardiac output is 5 L*min/1 and the resting heart rate decrease, _________ must increase if cardiac output is to remain the same.
stroke volume
The amount of blood ejected from the ventricles with each beat of the heart is the
stroke volume
The greatest differences between sedentary and trained individuals are seen in which variable?
stroke volume (SV)
Individual cells of the myocardium function collectively; the functionally collective unit is called
syncytial contraction
The contraction phase of the cardiac cycle is known as
systole
The blood vessels next smaller in size than veins are known as
venules
The majority of plasma is made up of
water
The exchange vessels are:
Capillaries
Stimulation of the cardiac accelerator nerves would result in which of the following responses?
"Increased heart rate" & "Increased cardiac contractility" only
Stimulation of the accelerator nerves to the heart results in
"an increased force of contraction" & "an increased rate of contraction" are correct
Blood flow returns through the venous system during exercise by
"skeletal muscle and respiratory muscle 'pumps'," "one-way valves," & "sympathetic venoconstriction"
Oxygen delivery to the tissue depends on
"the amount of oxygen tissue taken out of a given amount of blood" & "the amount of blood flowing through the tissue"
Stroke volume is determined by
"the volume of blood returned to the heart (preload)," "the force of contraction (contractility)," & "the resistance presented to the ventricles (afterload)"
Which of the following is (are) true of myocardial fibers?
(all are true) - Contain a high number of mitochondria - have an extensive capillary network - capable of using aerobic energy efficiently for contraction - they normally do not use anaerobic metabolism
Which of the following is a measure of systolic function?
(all of these) - average rate of blood flow out of a cardiac chamber - peak rate of flow out of a cardiac chamber - muscle fiber shortening velocity
All of the following are functions of the cardiovascular system except
(all of these) - temperature regulation - buffering of acidity - transportation of oxygen and carbon dioxide
Each cell within all tissues must be within a distance of _____ mm of the nearest capillary.
0.1
After filling, the atria contract approximately _____/10 of a second prior to the contraction of the ventricles.
1
The total amount of plasma can decrease _____% during intense physical activity.
10
The typical resting arterial blood pressure is _____/80 mmHg.
120
At rest, _____% to 20% of cardiac output goes to skeletal muscle.
15%
Reducing the radius of a blood vessel by one-half increases the resistance to flow _____-fold.
16
Blood volume in untrained women is _____L to 5 L.
4
In moderately trained or untrained individuals, stroke volume (SV) increases along with exercise intensity up to _____% to 50% of peak oxygen consumption.
40
The formed elements of the blood normally make up about _____% to 45% of blood.
40%
At rest, an untrained male has a cardiac output of approximately ____ L min−1.
5
Blood volume in untrained men is ____L to 6 L.
5
Plasma normally constitutes about _____% to 60% of the total blood volume.
55%
At rest, EF is equal to _____%.
60
At rest, venous vessels contain _____% of the body's total blood volume.
65%
A typical stroke volume at rest for a normal-sized untrained male is _____ mL.
70
During maximal exercise, skeletal muscle receives up to _____% to 85% of cardiac output.
80%
The first heart sound that you hear (S1) is the
AV valves closing
____ refers to slower-than-normal resting heart rate (less than 60 beats x min-1)
Bradycardia
________ is a sinus rhythm with a heart rate of less than 60 beats per minute.
Bradycardia
Which of the following is not an adaptation contributing to the decreased stroke volume seen at rest and submaximal exercise in endurance-trained athletes?
Decreased left ventricular muscle mass
Blood flows from an area of low pressure to areas of higher pressure.
False
By branching into a greater number of vessels in the transition from arteries to arterioles and then from arterioles to capillaries, less total vessel cross-sectional area is created for blood.
False
Cardiac output is the amount of blood ejected from the atria per unit of time.
False
During endurance exercise, there is an increase in diastolic blood pressure.
False
During exercise, a-vO2 diff decreases as oxygen consumption increases.
False
During maximal exercise, skin blood flow increases.
False
In strength training, the increase in left ventricular mass is due primarily to an increase in end-diastolic volume (EDV).
False
RBCs can reproduce and repair themselves, resulting in a normal life span of a year or two.
False
Resistance is opposition to blood pressure.
False
The amount of blood ejected from the left ventricle during one contraction is called heart rate.
False
The heart contains five hollow chambers surrounded by the myocardium and septum.
False
The majority of the formed elements of the blood is made up of WBCs and platelets.
False
The right ventricle has a greater wall thickness than the left ventricle.
False
Venous blood is blood that is leaving the heart and traveling toward other bodily tissues.
False
When a heart chamber is contracting, it is being filled with blood.
False
With a slower heart rate, the systolic phase of the cardiac cycle is longer.
False
With resistance training, ventricular end-diastolic volume (EDV) can increase both at rest and during physical activity.
False
An equation used to calculate cardiac output from oxygen consumption and arteriovenous oxygen difference (a-vO2 diff) is known as the
Fick equation
The left ventricle:
Is increased in size with strength training
During physical activity:
More oxygen is taken from the blood by muscle
These cells have the property of contractility:
Myocardial cells & working cells
Which ECG wave represents atrial contraction?
P wave
Which of the following does not help the ventricles to fill with blood?
Purkinje fibers
These cells have property of automaticity:
SA node, AV node, & Purkinje fibers
Ischemia can be demonstrated by an ECG when which segment is depressed?
ST
Which of the following question is false with regard to the tune media?
The tune media is thicker in veins
Arterial blood in the pulmonary arteries is deoxygenated.
True
Cardiac tissue receives the vast majority of its blood supply during diastole.
True
During endurance exercise, cardiac output increases.
True
EF could decrease with all other factors of cardiac function remaining the same if there is a greater afterload.
True
Epinephrine released by the adrenal gland increases heart rate.
True
Individual myocardial fibers generate little force.
True
Large veins contain one-way valves that allow blood flow only toward the heart.
True
The rate of blood flow is proportional to the pressure difference between two ends of a blood vessel.
True
There are valves located between the atria and ventricles to assist the flow in the desired direction.
True
The smallest of the veins are called
Venules
All of the following factors result in an increase in stroke volume (SV) at rest and during physical activity after endurance training except
a decrease in plasma volume
Intercommunication between two arteries that ensure blood flow to an area is known as
anastomosis
Peripheral blood pressure is highest in the
aorta
The __________ ( multiple words, do not abbreviate) is the difference between the amount of oxygen in 100 mL of arterial blood entering a tissue and the amount of oxygen in 100 mL of venous blood leaving a tissue.
arterial-venous oxygen difference
Arteries become smaller blood vessels known as
arterioles
An ECG can be used to determine all of the following except
blood pressure
During dynamic exercise
blood volume decreases
Aerobic and weight training can significantly reduce
both "resting systolic blood pressure" & "resting diastolic blood pressure"
The most numerous of all blood vessels are the
capillaries
The smallest blood vessels in which gaseous exchange takes place are known as
capillaries
One complete sequence of contraction and relaxation of the heart is called the
cardiac cycle
During exercise, heart rate has a linear relationship to peak oxygen consumption and
cardiac output
The amount of blood pumped per unit of time is the
cardiac output
Blood flow is equal to _____/_____.
change in pressure; resistance to flow
The blood vessel that supplies the heart with its own blood supply is known as the
coronary artery
In the left ventricle, if mean blood pressure in the aorta increases and contraction force of the ventricle does not change, stroke volume (SV) will
decrease
All of the following are characteristics of myocardial tissue except
divided into different types of muscle fibers
All of the following are factors that result in greater contractile force of the heart except
increased parasympathetic stimulation of the myocardium
Myocardial oxygen consumption
increases in relation to the intensity of exercise
The junction between cardiac muscle cells that forms the mechanical and electrical connection between the two cells are the
intercalated discs
The spread of electrical impulse among the muscle fibers of the heart:
is achieved through intercalated discs
Blood flow from the left side of the heart to the tissues of the body is known as the
peripheral circuit
During diastole, the right atrium is filled with venous blood from the
peripheral circulation
All nutrient exchange between tissue and blood occurs within the
peripheral cycle
The right ventricle:
pumps blood to the pulmonary circulation
Adaptations to the cardiovascular system detected at rest are different between endurance- and strength-trained athletes.
true
Endurance training results in a decrease in resting heart rate.
true
Measures of diastolic function are similar to those of systolic function except they relate to the rate at which a chamber fills with blood.
true
The right side of the heart receives blood from the peripheral circulation and pumps blood to the pulmonary circulation.
true
____________ prevent unwanted blood flow in the heart.
valves
__________ refers to a decrease in the interior radius of blood vessels.
vasoconstriction
Because of their ability to pool large volumes of blood and become reservoirs for blood, another name for this blood vessel is capacitance vessels
vein
Which of the following is NOT a factor that aids in venous return?
venodilation
The major influence on end diastolic volume (EDV) is:
venous return
The movement of air into and out of the lungs, or breathing, is properly referred to as pulmonary __________.
ventilation
The T wave reflects
ventricle repolarization
End-diastolic volume is the amount of blood in the _____ at the end of the diastolic phase.
ventricles
The QRS segment of an ECG illustrates
ventricular depolarization
