Physiology Cardiovascular Questions (Ch. 14)

In the condition known as complete heart block, what happens?

B) Electrical signals from the SA node never reach the ventricles, so the contraction of the atria is not coordinated with the contraction of the ventricles.

When the heart is in fibrillation,

C) effective pumping of the ventricles ceases because the myocardial cells fail to work as a team, and the brain cannot get adequate oxygen.

Electrical shock to the heart is usually used to treat

ventricular fibrillation.

ECGs

C) show the summed electrical potentials generated by all cells of the heart.

The P wave of an ECG corresponds to

A) the depolarization of the atria.

The QRS complex of an ECG corresponds to

B) the progressive wave of ventricular depolarization.

A heart rate of 125 beats per minute could be correctly termed

B) tachycardia.

Ventricular contraction

C) begins just after the Q wave.

Atrial contraction

D) begins during the latter part of the P wave.

In electrocardiography, a lead is a(n)

B) pair of electrodes.

Which event happens at the start of a cardiac cycle?

B) The SA node fires.

In order for blood to enter the heart,

D) the atria must not only be at rest but the atrial pressure must be lower than the veins.

Which of the following events result in the first heart sound?

B) The AV valves close.

During the isovolumic phase of ventricular systole,

B) the atrioventricular valves and semilunar valves are closed.

During the cardiac cycle,

B) the QRS complex of the ECG precedes the increase in ventricular pressure.

During ventricular systole,

C) the AV valves are closed.

During ventricular ejection,

A) the ventricles are in systole.

The term used to describe the amount of blood in the ventricle available to be pumped out of the heart during the next contraction is

C) end-diastolic volume (EDV).

The volume of blood ejected from each ventricle during a contraction is called the

C) stroke volume.

The cardiac output is equal to

B) the product of heart rate and stroke volume.

The term that describes the volume of blood circulated by the heart in one minute is

A) cardiac output (CO).

Epinephrine and norepinephrine increase ion flow through ________ channels.

E) If and Ca2+

According to Starling's law of the heart, the cardiac output is directly related to the

C) venous return.

Which of these will increase the heart rate?

D) both sympathetic stimulation and application of epinephrine to the SA node

Stimulation of the beta receptors on heart muscle results in

A) the formation of cAMP.

Drugs known as beta blockers will

B) decrease heart rate.

an AV valve that has three flaps

A. tricuspid valve

a semilunar valve that has the right ventricle on one side

D. pulmonary valve

also called the mitral valve

B. bicuspid valve

has three cuplike leaflets and has the aorta on one side

C. aortic valve

immediately followed by ventricular contraction

QRS complex

atrial contraction

PR segment

ventricular repolarization

T wave

ventricular depolarization

QRS complex

atrial depolarization

P wave

the amount of blood pumped out of the heart during one contraction

stroke volume (SV)

the amount of blood in the ventricle available to be pumped out of the heart during one contraction

end-diastolic volume (EDV)

the volume of blood circulated by the heart in one minute

cardiac output (CO)

the amount of blood left in the ventricle after it contracts

end-systolic volume (ESV)

The chambers of the heart that pump blood into the arteries are the ________.

ventricles

The chambers of the heart that receive blood from the veins are the ________.

atria

The primary function of the cardiovascular system is ________.

to transport material to and from all parts of the body

79) ________ are blood vessels that carry blood away from the heart.

Arteries

80) ________ are blood vessels that carry blood toward the heart.

Veins

The cardiovascular system is made up of ________, ________, and ________.

the heart, blood vessels, blood

The most proximal arteries to branch from the aorta are the ________.

coronary arteries

Name the three portal systems in the body.

1. hepatic portal system

2. renal portal system

3. hypothalamic-hypophyseal portal system

The ________ circuit carries blood to and from the alveoli of the lungs.

pulmonary

The ________ circuit carries blood to and from all parts of the body except the alveoli of the lungs.

systemic

The pressure created in the ventricles is called the ________ pressure because ________.

driving, it is the force that drives blood through the blood vessels

The term for reduced blood flow to the cardiac muscle is ________.

coronary ischemia

The ________ directs blood from the ________ of the heart to the lungs. Backflow of blood to the heart is prevented by ________. Blood from the lungs returns to the heart via ________.

pulmonary trunk, right ventricle, pulmonary valves, pulmonary veins

The heart is enclosed in the ________.

pericardial membrane

The superior portion of the heart where the major blood vessels enter and exit is the

________.

base

The inferior point of the heart is called the ________.

apex

The ________ is a wall that separates the two sides of the heart.

septum

The muscle layer of the heart wall is the ________.

myocardium

The heart is encased in a tough membranous sac called the ________. The heart is composed mostly of ________ muscle tissue, called the ________.

pericardium, cardiac, myocardium

95) The opening between each atrium and its ventricle is guarded by the ________, which connects the ventricular side to collagenous tendons, called ________. ________ muscles provide stability for these tendons.

atrioventricular valve, chordae tendineae, Papillary

Cell junctions in contractile cells are called ________, which consist of two components: ________ and ________.

intercalated disks, desmosomes, gap junctions

The ________ are calcium channels in cardiac contractile cells. Opening them causes ________.

ryanodine receptors, calcium-induced calcium release

The AV node delays the transmission of action potentials slightly to allow ________.

the atria to complete their contraction before ventricular contraction begins

99) The cells responsible for establishing the rate of a cardiac contraction are the ________.

nodal cells

A heart with cells contracting rapidly in a disorganized manner, with no effective pumping action, is said to be in ________.

fibrillation

A tracing of the electrical activity of the heart, monitored by electrodes placed on the skin, is called a(n) ________.

electrocardiogram

The period of time from the beginning of one heartbeat to the beginning of the next is termed the ________.

cardiac cycle

Abnormal patterns of cardiac activity are known as ________.

arrhythmias

A resting heart rate of less than 60 beats per minute is identified as ________.

bradycardia

A resting heart rate above 100 beats per minute is identified as ________.

tachycardia

An increase in blood vessel diameter is known as ________.

vasodilation

The contraction phase of the cardiac cycle is termed ________.

systole

The period when blood is pushed into the arteries is called ________.

ventricular ejection

Listening to the heart through the chest wall is called ________.

auscultation

Narrowing of the opening of a heart valve is referred to as ________.

stenosis

The ________ is the amount of blood in a ventricle at the beginning of systole.

end-diastolic volume

The ________ is the amount of blood in a ventricle after it has contracted and before it begins to refill.

end-systolic volume

The rule that states "Within limits, the heart pumps all of the blood that returns to it" is known as the ________.

Frank-Starling Law of the Heart

The amount of blood returning to the heart is the ________.

venous return

Place these structures in the order that blood returning to the heart from the body would pass through them.

C) 3, 1, 4, 6, 2, 5

right side atrium, right ventricle, pulm art, pulm vein, left atrium, left ventricle

If blood pressure doubled at the same time that the peripheral resistance doubled, the blood

flow through a vessel would be

E) unchanged.

Which of the following conditions would have the greatest effect on peripheral resistance?

doubling the diameter of a vessel

Which statement is NOT true regarding cardiac muscle?

Cardiac muscle cells must obey the all-or- none law of contraction.

If the membranes of the cardiac muscle cells in the SA node become more permeable to potassium ions,

B) the heart rate will decrease.

As a result of the long refractory period, cardiac muscle cannot exhibit

C) tetany.

Ivabrandine selectively blocks If channels in the heart. Which statement would be true concerning a patient who is taking this drug?

A) The drug would slow down this individual's heart rate.

Put these autorhythmic cells into the correct order for conveying electrical signals through a normal heart.

B) 5, 2, 4, 1, 6, 3

SA, internode pathway, bundle of His, Bundle branches, purkinje fibers

The ECG of a person suffering from complete heart block would show

E) more P waves than QRS complexes per minute.

If the connection between the AV node and bundle of His becomes blocked,

B) the ventricles will beat more slowly.

If a myocardial infarction results in the formation of scar tissue along the pathway of the left bundle branch,

A) cardiac arrhythmias may occur.

Abnormally slow conduction through the ventricles would change the ________ in an ECG tracing.

C) QRS complex

If there is a blockage between the AV node and the AV bundle, how will this affect the

appearance of the electrocardiogram?

C) There will be more P waves than QRS complexes.

Put these phases of the cardiac cycle in the correct order.

C) 3, 5, 6, 4, 2, 1, 8, 7

atrial systole, completion of ventricular filling, beginning of ventricular systole, closure of the AV valves, opening of semilunar valves, ventricular ejection, ventricular relaxation

Left ventricular pressure is higher than pressure in the aorta during

ventricular diastole only.

In which of the following situations would the end-systolic volume (ESV) be the greatest?

when parasympathetic stimulation of the heart is increased

A certain drug decreases heart rate by producing hyperpolarization in the pacemaker cells of the heart. This drug probably binds to

B) muscarinic receptors.

Under which set of circumstances would the diameter of peripheral blood vessels be the greatest?

B) decreased sympathetic stimulation

Acetylcholine slows the heart rate by

E) increasing the permeability to K+ and decreasing the permeability to Ca2+.

Sympathetic stimulation increases the heart rate by

A) just increasing ion influx, thus increasing the rate of depolarization.

In which situation would the stroke volume be the greatest?

A) when venous return is increased

Manganese ions block the calcium channels in the cardiac muscle membrane. How would the presence of manganese in the extracellular fluid affect the contraction of the heart muscle?

C) The heart would beat less forcefully.