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