Chapter 20 Cardiovascular System

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The average end-diastolic volume of the ventricles is about ______, where as the end-systolic volume is about ________

130 mL, 50 mL

During the ejection phase of the cardiac cycle, blood exits the left ventricle through the ____

Aorta

What is the effect of norepinephrine on the heart?

B) It increases the rate and strength of contraction. Feedback: Norepinephrine is released by sympathetic postgangionic fibers.

Any factor that alters heart rate is called

B) a chronotrope

The visceral pericardium is also called the

B) epicardium.

The anterior border of the ventricles is marked by the

B. interventricular septum

Circumflex

Bend around

8. In which septum is it normal to find openings in the adult? a. interatrial septum b. interventricular septum c. atrioventricular septum d. all of the above

Sinus

Cavity

During isovolumetric contraction the atrioventricular (AV) valves are ______

Closed

Ovalis

Egg shaped

Atrium

Entry Hall

step 7 (systemic circuit)

From the left atrium blood flows through the mitral valve to the left ventricle

Why does the left ventricle have a thicker myocardial wall?

It has to pump blood to the body.

The great cardiac vein collects blood from the _____ _____ surface of the heart

Left anterior

Papilla

Nipple (bump)

_____________ is the most superficial layer enclosing the heart

Parietal pericardium

Cusp

Point

Which chamber initially receives blood from the systemic circuit? a. left atrium b. left ventricle c. right atrium d. right ventricle

Right Atrium

The pacemaker of the heart is the

SA node

What is the "pacemaker" of the heart?

SA node

The contraction phase of the cardiac cycle is called:

Systole

The long refractory period observed in cardiac muscle prevents what?

Tetanic contractions of the cardiac muscle

Which of the following is true about the heart?

The apex end points downward at about the 5th intercostal space.

The pericardial sac is lined with

step 1 (pulmonary circuit)

The right atrium receives oxygen poor blood from the body via the venue (superior vena cava and the inferior vena cava) and a coronary sinus

The pulmonary trunk and aorta are derived from which primitive heart structure? a. bulbus cordis b. primitive ventricle c. sinus venosus d. truncus arteriosus

Truncus arteriosus

Vena

Vein

The coronary sulcus is a groove on the outside of the heart that marks the division between the a. atria and ventricles b. left and right ventricles c. aorta and pulmonary trunk d. left and right atria

a. atria and ventricles

If the SA node is nonfunctional, which of the following is most likely to occur? a. the heart will be desensitized b. Tachycardia will develop c. Another portion of the heart will become the pacemaker d. the heart will go into defibrillation e. the heart will go into systole (stop)

c. Another portion of the heart will become the pacemaker

Which of the following components of an ECG is not correctly matched with the corresponding event occurring in the heart? a. P wave- atrial depolarization b. PR interval- AV node conduction c. T wave- atrial repolarization d. QRS complex- ventricular depolarization

c. T wave- atrial repolarization

The chordae tendineae are made out of

collagen fibers.

Which choice below would NOT increase cardiac output?

decrease heart rate, no change in stroke volume

Increased input from the baroreceptors to the cardiac control center would cause what to occur?

decreased sympathetic stimulation and increased parasympathetic stimulation Feedback: The baroreceptors are stimulated by high blood pressures. By decreasing the rate and force of contraction, the ANS can reduce the blood pressure.

The spontaneous opening of sodium fast channels marks the beginning of _______of a myocardial cell

depolarization

ventricles

discharging chambers of the heart

coronary sinus

drains blood into the right atrium

Blood does not enter or leave the ventricles during the period called a. atrial systole. b. active and passive filling. c. rapid filling. d. ejection. e. isovolumetric contraction.

If the heart receives more sympathetic stimulation than parasympathetic stimulation, the heart will a. contract with less force but at a faster rate b. decrease both its rate and force of contraction c. contract with greater force but at a slower rate d. decrease rate, but increase force of contraction e. increase its rate and force of contraction

Cardiac muscle cells a. have smooth ER but no T tubules b. form the heart valves c. develop significant oxygen during systole d. do not contain actin and myosin like skeletal muscles cells e. are maintained by an extensive capillary network

e. are maintained by an extensive capillary network

The period of isovolumetric contraction is immediately followed by a. isovolumetric relaxation b. passive ventricular filling c. AV node depolarization d. atrial contraction e. the period of ejection

e. the period of ejection

When ventricular pressure exceeds atrial pressure, the

ejection occurs

An electrocardiogram actually records

electrical changes that occur in the myocardial cells

The amount of blood in the ventricles just before they contract is called the

end diastolic volume

The inner lining of the heart is the

endocardium.

Another name for the visceral pericardium is the

epicardium

The visceral pericardium also forms the ________ of the heart wall.

epicardium

The visceral pericardium is also called the

epicardium

Another name for the visceral pericardium is the

epicardium.

The pericardial layer that is tough and protective is the

fibrous pericardium

An incompetent pulmonary semilunar valve could result in less blood reaching the

lungs

pectinate muscles

muscle ridges in the anterior atrial wall

The pericardial sac is lined with

parietal pericardium

The chordae tendineae prevents atrioventricular valves cusps from?

prolapsing into the atria during ventricular systole

Atria

receiving chambers of the heart

The pericardial fluid

reduces friction as the heart beats

Mediastinum

region behind the sternum between the lungs

veins

return blood to the heart

Blood in the superior vena cava will enter the

right atrium

Blood in the superior vena cava will enter the _____. aorta right atrium pulmonary trunk pulmonary arteries pulmonary veins

right atrium

Which chamber initially receives blood from the systemic circuit? Select one: a. left atrium b. right ventricle c. right atrium d. left ventricle

right atrium

What are the four chambers of the heart?

right atrium, left atrium, right ventricle, left ventricle

Which of the following heart chambers is correctly associated with the blood vessel that enters or leaves it?

right ventricle - pulmonary trunk

Which portion of the ECG corresponds to repolarization of the atria? a. P wave b. QRS complex c. T wave d. none of the above: atrial repolarization is masked by ventricular depolarization

None of the above: atrial repolarization is masked by ventricular depolarization

. Which of the following is unique to cardiac muscle cells? a. Only cardiac muscle contains a sarcoplasmic reticulum. b. Only cardiac muscle has gap junctions. c. Only cardiac muscle is capable of autorhythmicity d. Only cardiac muscle has a high concentration of mitochondria.

Only cardiac muscle is capable of autorhythmicity

Step 6 (systemic circuit)

Oxygen Rich blood enters the left atrium via four pulmonary veins

Step 9 systemic circuit

Oxygen rich blood is delivered to the body tissues by the systemic arteries.

Step 5 (pulmonary circuit)

Oxygen rich blood returns the heart via four pulmonary veins

In an EKG taken from a person who has no SA node activity, which component will NOT appear?

P wave

What structures pull on the tendinous cords (chordae tendineae) and hold them taut during ventricular contraction?

Papillary muscles

What is the superficial fibrous covering of the heart that is composed partly of dense irregular connective tissue?

Parietal pericardium

Which correctly describes the heart's apex?

Projects slightly anteroinferiorly toward the left side of the body

Which vessels transport blood to the right and left lungs?

Pulmonary arteries

Pressure in the right ventricle must exceed pressure in the ____ ____ before the right ventricle can eject blood

Pulmonary trunk

step 4 (pulmonary circuit)

Pulmonary trunk branches into left and right pulmonary arteries which carries blood into the lungs where the blood unloads carbon dioxide and picks up oxygen

Which component of the heart conduction system would have the slowest rate of firing? a. atrioventricular node b. atrioventricular bundle c. bundle branches d. Purkinje fibers

Purkinje fibers

Abnormally slow conduction through the ventricles would change the shape of the _____ in an ECG tracing

QRS complex

In a normal electrocardiogram, the

QRS complex results from ventricular depolarization

In a normal electrocardiogram, the P wave results from repolarization of the atria. QRS complex results from ventricular depolarization. P wave occurs after the QRS complex but before the T wave. T wave represents depolarization of the atria. repolarization of the atria is clearly visible.

QRS complex results from ventricular depolarization.

Which of the following parts of the cardiac conduction system is correctly matched with its location?

SA node - right atrium near the opening of the superior vena cava

In which choice are the components of the cardiac conduction system listed in the CORRECT order in which they conduct the cardiac impulse?

SA node, AV node, AV bundle, Purkinje fibers

Which of the following sequences for the conducting system is correct? a. AV node, SA node, bundle branches, AV bundle, Purkinje fibers b. SA node, AV bundle, AV node, bundle branches, Purkinje fibers c. Purkinje fibers, bundle branches, AV node, AV bundle, SA node d. SA node, AV node, AV bundle, bundle branches, Purkinje fibers e. AV node, AV bundle, SA node, Purkinje fibers, bundle branches

SA node, AV node, AV bundle, bundle branches, Purkinje fibers

The second heart sound is heard when the ______ valves are closing

Semilunar

The relationship between preload and stroke volume is known as Select one: a. Starling's Law of the heart. b. minute volume. c. cardiac reserve. d. extrinsic regulation.

Starling's Law of the heart.

Name three vessels that deliver oxygen-poor blood to the right atrium

Superior vena cava, inferior vena cava, coronary sinus

Which of the following is NOT true about the heart? The heart is about the size of a closed fist. The heart is located in the mediastinum. The apex of the heart is directed superiorly and to the left. Knowing the heart's position is important for effective CPR.

The apex of the heart is directed superiorly and to the left.

which valves are anchored by Chordae Tendineae

The atrioventricular (AV Valves) Tricuspid valve and Mitral Valve are anchored by Chordae Tendineae

Which of the following is NOT true about the heart?

The base rests on the diaphragm.

What is the pericardial sac?

The dense network of collagen fibers that stabilize the heart

Concerning heart sounds, which of the following is correct? The first heart sound occurs at the beginning of ventricular systole. The second heart sound is heard when the AV valves are closing. The first heart sound is the sound of the semilunar valves closing. The second heart sound occurs when blood flows into the superior vena cava. The first heart sound occurs at the beginning of ventricular diastole.

The first heart sound occurs at the beginning of ventricular systole.

What is the function of the fluid that fill the pericardial sac

The function of the Pericardial fluid is that lubricates and reduces friction between the visceral and parietal pericardium. reduces friction between the layers of the serous pericardium as the heart moves

Which of these statements is true?

The great cardiac vein collects blood from the anterior surface of the heart.

Describe the role of the pulmonary circuit

The pulmonary circuit consists of blood vessels that carries blood to and from the lungs and its function is to provide a path for gas exchange.

Using their own observations explain how the operation of the semi lunar valves differs from that of the atrioventricular valves

The semi lunar valves closes when blood flows backward toward the Ventricle and the cusps Fill with blood. when semilunar valves open it allows blood to flow to the ventricles and onto the rest of the body the tricuspid valve closes and allows deoxygenated blood to fill right atrium while the mitral valve closes and allows the left atrium to fill with oxygenated blood the AV valves when open allows blood to be carried to the right ventricle then to the pulmonary artery and ultimately to the lungs AV valves when open also allow blood to be carried from the left ventricle and ultimately to the Aorta

Describe the role of the systemic circuit

The systemic circuit's role is to provide a path of blood vessels that carry blood to and from all body tissues

Describe the unique anatomical features of cardiac muscle what role does the unique structure of cardiac play and it's function

The unique feature of cardiac muscle is the presence of intercalated discs. Its role is to maintain the 3-D structure of the heart in addition it allows for communication between cardiac cells

The fibrous skeleton of the heart serves as electrical insulation between the atria and the ventricles.

True

True or False: If cardiac muscle fibers are slightly stretched, they have a stronger contraction force.

True

True or false: The great cardiac vein collects blood from the anterior surface of the heart

True

Ventricular relaxation immediately follows ________. a. atrial depolarization b. ventricular repolarization c. ventricular depolarization d. atrial repolarization

Ventricular repolarization

Blood in the pulmonary veins returns to the a. left atrium. b. left ventricle. c. right ventricle. d. coronary sinus. e. right atrium.

Pressure in the right ventricle must exceed pressure in the ____ before the right ventricle can eject blood. a. pulmonary trunk b. coronary sinus c. aorta d. pulmonary veins. e. superior vena cava

Which vessels empty blood into the left atrium? a. pulmonary veins b. pulmonary trunk c. pulmonary arteries d. right atrium e. aorta

Which describes the endocardium? a: Has single layer of epithelium b: Has layer of areolar connective tissue c: Epithelial cells are squamous d: Epithelial cells are cuboidal e: Has layer of adipose connective tissue f: Has patches of myocardium

a, b, c

Which are functions performed by the fibrous skeleton of the heart? a: Separates the atria and ventricles b: Anchors the heart valves c: Provides electrical insulation between the atria and ventricles d: Provides the framework for the attachment of the myocardium e: None of these are true functions of the fibrous skeleton of the heart.

a, b, c, d

The plateau phase of the cardiac contractile cell action potential is caused by Select one: a. Ca2+ inflow b. Cl- inflow c. Na+ outflow d. K+ outflow

a. Ca2+ inflow

In which choice are the components of the heart placed in the correct order of decreasing intrinsic rhythm? a. SA node, AV node, Purkinje cells b. Purkinje cells, AV node, SA node c. SA node, Purkinje cells, AV node d. AV node, SA node, Purkinje cells

a. SA node, AV node, Purkinje cells

An incompetent mitral valve may cause blood to back up into the a. left atrium b. left ventricle c. aorta d. right atrium e. coronary circulation

a. left atrium

Which of the following phrases would apply to cardiac muscle cells? a. posses special cell-to-cell contacts called intercalated discs b. are multinucleated like skeletal muscle cells c. develop a significant oxygen debt during systole d. are organized in parallel columns or bundles e. contain actin but no myosin

a. posses cell to cell contacts called intercalated discs

Contraction of the papillary muscles would a. prevent the AV valves from protruding into the atria b. open semilunar valves c. eject blood from ventricles d. close semilunar valves e. cause the atria to eject their contents into the ventricles

a. prevent the AV valves from protruding into the atria

The tricuspid valve is closed a. during passive filling of the ventricles b. when the mitral valve is open c. during ejection d. while the atria are contracting e. during active filling of the ventricles

What is the foramen oval? a. an opening between the right and left atria in the embryo and fetus b. an oval hole in the pericardium in the embryo and fetus c. an opening between the right and left ventricles in the embryo and fetus d. an opening between the pulmonary truck and the aorta in the embryo and fetus

a? b?

The period of time in which the myocardium is insensitive to further stimulation is called

absolute refractory period

The period of time in which the myocardium is insensitive to further stimulation is called the Select one: a. AV period. b. ectopic focus. c. SA period. d. absolute refractory period. e. hyperpolarization period.

absolute refractory period.

When comparing cardiac muscle cells and skeletal muscle cells

action potentials are conducted from cell to cell only in cardiac muscle

When a prepotential in the SA node reaches threshold

an action potential is generated

What factor could cause an increase in the size of the QRS complex in an electrocardiogram?

an enlarged heart, there is a larger amount of electrical activity during ventricular depolarization

An auricle is

an external extension of the atrial wall

Within normal limits, an increase in preload leads to

an increase in cardiac output and force of left ventricular contraction

A direct connection between arteries is called a/an Select one: a. auricle. b. anastamosis. c. sulcus. d. sinus.

anastamosis

The procedure whereby a small balloon is placed into a partially occluded coronary artery and then inflated to increase blood flow through the artery is called a(n) angioplasty. coronary bypass. urokinase injection. tissue plasminogen activation. angiogram.

angioplasty.

If the SA node is nonfunctional, which of the following is most likely to occur?

another portion of the heart will become the pacemaker

During the ejection phase of the cardiac cycle, blood exits the left ventricle through the

aorta

What vessel exits the left ventricle? pulmonary trunk pulmonary vein aorta pulmonary artery

aorta

Blood leaving the left ventricle goes through which of the following valves?

aortic semilunar

As soon as left ventricular pressure exceeds the pressure in the aorta, the

aortic semilunar valve opens

Ventricular contraction begins at the

apex of the heart

Ventricular contraction begins at the Select one: a. AV bundle. b. apex of the heart. c. top of the ventricles. d. superior portion of the interventricular septum. e. base of the heart.

apex of the heart

Cardiac muscle cells

are maintained by an extensive capillary network

mitral and tricuspid valves prevent backflow into

atria

The action potentials are slowed at the AV node to allow the

atria to complete their contraction

The action potentials are slowed at the AV node to allow the Select one: a. atria to complete their contraction. b. ventricles to completely empty of blood. c. ventricles to repolarize. d. pacemaker to reset for the next beat. e. atria to begin their contraction.

atria to complete their contraction.

Concerning heart sounds, which of the following is correct? a. The first heart sound is the sound of the semilunar valves closing b. The first heart sound occurs at the beginning of ventricular systole c. The second heart sound occurs when blood flows into the superior venacava d. The first heart sound occurs at the beginning of ventricular diastole e. The second heart sound is heard when the AV valves are closing

b. The first heart sound occurs at the beginning of ventricular systole

Angina pectoris is chest pain caused by reduced a. action potentials from SA node b. blood supply to cardiac muscle c. fluid in the pericardial sac d. stimulation of the myocardium e. contractility of the heart

b. blood supply to cardiac muscle

What event(s) occur during the QRS complex of an ECG? a. depolarization of the atria b. depolarization of the ventricles and repolarization of the atria c. depolarization of the atria and repolarization of the ventricles d. repolarization of the ventricles

b. depolarization of the ventricles and repolarizatation of the atria

Which of the following factors would cause an increase in heart rate? a. Vagal stimulation b. increased epinephrine release from the adrenal medulla c. increased production of atrial natriuretic factor d. stimulation of baroreceptors in the aorta e. increased parasympathetic stimulation

b. increased epinephrine release from the adrenal medulla

The period of ejection is immediately followed by a. passive ventricular filling b. the period of ejection c. AV node depolarization d. atrial contraction e. isovolumetric relaxation

b. the period of ejection

Blood vessels enter and exit from the _____ of the heart.

base

Blood vessels enter and exit from the _____ of the heart. Select one: a. trigone b. auricles c. apex d. base e. inferior aspect

base

Blood vessels enter and exit from the _____ of the heart. apex base auricles trigone inferior aspect

base

40 to 60 per minute

begins at the apex of the heart and pushes blood towards the semilunar valves

The AV valve that is located on the same side of the heart as the origin of the aorta is the bicuspid or mitral valve. tricuspid valve. aortic semilunar valve. pulmonary semilunar valve. coronary sinus valve.

bicuspid or mitral valve

The atrio-ventricular valve that is located on the same side of the heart as the origin of the aorta is the

bicuspid valve

The higher the _____, the greater the cardiac output. Select one: a. blood pressure in the aorta b. venous return c. level of acetylcholine released at the SA node d. extracellular K+ concentration

blood pressure in the aorta

Angina pectoris is chest pain caused by reduced stimulation of the myocardium. blood supply to cardiac muscle. fluid in the pericardial sac. contractility of the heart. action potentials from SA node.

blood supply to cardiac muscle.

Angina pectoris is chest pain caused by reduced

blood supply to the cardiac muscle

Pulmonary circuit

blood vessels that carry the blood to and from the lungs

systemic circuit

blood vessels that transport the blood to and from areas other than the lungs

The fibrous skeleton of the heart is important because it provides:

both structural support and electrical insulation.

Compare and contrast the structure of the mitral and tricuspid valves

both valves have been flaps the tricuspid valve has three cusps and the mitral valve has two cusps

How is the heart muscle nourished?

by the coronary arteries

Blood in the superior vena cava will enter the ____. a. pulmonary veins b. aorta c. right atrium d. pulmonary trunk e. pulmonary arteries

If cardiac muscle cells are unable to repolarize, this would cause a. no harm. These cells can spontaneously depolarize anyway. b. cardiac output to increase. c. the heart rate to decrease. It might cause cardiac arrest. d. an increased demand on mitochondria to produce more ATP. e. tachycardia.

The right atrium receives blood from a.the lungs and the body. b. the lungs and the heart. c. the body and the heart. d. the heart.

When comparing cardiac muscle cells and skeletal muscle cells, a. the rate of action potential propagation is faster in cardiac muscle b. both are voluntary c. action potentials are conducted from cell to cell only in cardiac muscle d. both possess intercalated discs e. only skeletal muscle has a plateau phase in its contraction cycle

c. action potentials are conducted from cell to cell only in cardiac muscle

In the cardiac cycle, a. the left atrium contracts before the right atrium b. all four chambers of the heart contract at the same time c. all four chambers of the heart are in diastole at the same time d. the right atrium and the right ventricle contract simultaneously

c. all four chambers of the heart are in diastole at the same time

Occlusion of which of the following would primarily damage the posterior wall of the heart? a. pulmonary artery b. coronary sinus artery c. circumflex artery d. right marginal artery e. right coronary artery

c. circumflex artery

The spontaneous opening of sodium channels marks the beginning of ____ of a myocardial cell. a. repolarization b. afterpolarization c. depolarization d. isopolarization e. hyperpolarization

c. depolarization

During the isovolumetric contraction period of the cardiac cycle, a. AV and semilunar valves are closed b. the atria are contracted c. ventricular volume increases d. pressure in the ventricle decreases e. blood is pumped into the large arteries

c? a?

Stroke volume times heart rate equals

cardiac output

The amount of blood ejected from the heart in one minute is called the

cardiac output

The product of the stroke volume times the heart rate is known as the

cardiac output

Mean arterial pressure is cardiac output times peripheral resistance. end-diastolic volume minus end-systolic volume. maximum cardiac output minus cardiac output when at rest. heart rate times stroke volume. stroke volume times peripheral resistance.

cardiac output times peripheral resistance.

The product of the stroke volume times the heart rate is known as the end-diastolic volume. end-systolic volume. cardiac output. cardiac reserve. venous return.

cardiac output.

The difference between resting and maximal cardiac output is

cardiac reserve

Heart enlargement or ___________________ frequently occurs due to prolonged hypertension

cardiomegaly

Chemoreceptors sensitive to blood oxygen levels are primarily located in the medulla oblongata. carotid arteries. right atrium. left ventricle. jugular veins.

carotid arteries.

arteries

carry blood away from the heart

Which of the following is associated with atrioventricular valves?

chordae tendineae, cusps, papillary muscles

The papillary muscles attach to the cusps of the atrioventricular valves by means of the

chordae tendineae.

Which of the following might increase the risk for cardiovascular disease? Select one: a. chronic stress b. stopping smoking c. maintaining normal cholesterol levels d. exercise e. lots of fiber in the diet

chronic stress

Occlusion of which of the following would primarily damage the left ventricle?

circumflex artery

Occlusion of which of the following would primarily damage the posterior wall of the heart? Select one: a. coronary sinus artery b. right coronary artery c. circumflex artery d. right marginal artery e. pulmonary artery

circumflex artery

Occlusion of which of the following would primarily damage the posterior wall of the heart? circumflex artery pulmonary artery right marginal artery coronary sinus artery right coronary artery

circumflex artery

The chordae tendineae Select one: a. connect the flaps of the AV valves to the papillary muscles. b. are a part of the myocardium. c. are part of the conducting system of the heart. d. are found in the interventricular septum. e. connect the atria to the ventricles.

connect the flaps of the AV valves to the papillary muscles.

The first branches which come off of the aorta are the right and left ____________ arteries.

coronary

What are the first blood vessels to branch from the aorta as it leaves the heart?

coronary arteries

The great cardiac vein and middle cardiac vein empty into a venous cavity called the

coronary sinus

The great cardiac vein and middle cardiac vein empty into a venous cavity called the

coronary sinus.

All cardiac veins empty into the ____, which then empties into the ____.

coronary sinus; right atrium

All cardiac veins empty into the _________, which then empties into the _______.

coronary sinus; right atrium

All cardiac veins empty into the _________, which then empties into the _______. coronary sinus; left atrium coronary sinus; right atrium great cardiac vein; right atrium great cardiac vein; superior vena cava inferior vena cava; left atrium

coronary sinus; right atrium

The epicardium

covers the surface of the heart

Another name for the visceral pericardium is the a. visocardium. b. isocardium. c. myocardium. d. epicardium. e. endocardium.

Any factor that causes a change in heart contractility is called a. a chronotope b. an isotope c. a chemotrope d. an inotrope

d. an inotrope

The AV valve that is centrally located on the same side of the heart as the origin of the aorta is the a. tricuspid valve b. coronary sinus valve c. aortic semilunar valve d. bicuspid or mitral valve e. pulmonary semilunar valve

d. bicuspid or mitral valve

Baroreceptor reflexes a. are triggered by increased blood osmolarity b. correct changes in blood pH c. do not have impact on the activity of the heart d. can change heart rate e. are of minor importance to humans

d. can change the heart rate

Which of the following might increase the risk for cardiovascular disease? a. stopping smoking b. exercise c. maintaining normal cholesterol levels d. chronic stress e. lots of fiber in the diet

d. chronic stress

Which of the following is NOT a major opening into the right atrium? a. superior vena cava b. inferior vena cava c. coronary sinus d. pulmonary vein

d. pulmonary vein

The figure illustrates the cardiac action potential. What does "C" represent? a. early repolarization phase b. depolarization phase c. final repolarization phase d. plateau phase

What event(s) occur during the QRS complex of an ECG? Select one: a. repolarization of the ventricles b. depolarization of the atria and repolarization of the ventricles c. depolarization of the atria d. depolarization of the ventricles and repolarization of the atria

depolarization of the ventricles and repolarization of the atria

The product of the stroke volume times the heart rate is known as the a. venous return b. end-systolic volume c. cardiac reserve d. end-diastolic volume e. cardiac output

e. cardiac output

An incompetent pulmonary semilunar valve could result in less blood reaching the a. aorta b. right ventricle c. right atrium d. heart muscle e. lungs

e. lungs

Contraction of the ventricles is referred to as ventricular a. fibrillation b. diastole c. depolarization d. ischemia e. systole

e. systole

When left arterial pressure exceeds left ventricular pressure a. left ventricular ejection begins b. ventricular volume decreases c. the tricuspid valve opens d. aortic blood pressure begins to rise e. the bicuspid (mitral) valve opens

e. the bicuspid (mitral) valve opens

Which layer of the heart is correctly matched with the tissue of which it is composed?

fibrous pericardium - dense connective tissue

The loose-fitting sac around the heart is the

fibrous pericardium.

The atria are electrically isolated from the ventricles by the

fibrous skeleton

Visceral pericardium

fluid membrane that is closest to the heart

atrioventricular valves

folds of fibrous that extend into the openings between the atria and ventricles

An obstruction in the pulmonary trunk would prevent blood

from picking up oxygen in the lungs

Although cardiac muscle cells are short and branched, special cell connections allow them to

function as a single unit, both electrically and functionally

Action potentials pass from one myocardial cell to another through areas of low electrical resistance called

gap junctions

Intercalated discs include these structures)

gap junctions, desmosomes

Stroke volume and heart rate may increase cardiac output to 18-30 L/min in

healthy adults

myocardium

heart muscle tissue

Which of the following regarding heart sounds is TRUE?

heart sounds are caused by turbulent blood flow

Congestive heart failure(CHF) Is an inability of the heart to pump sufficient blood to the body. One sign of CHF is excess fluid in the tissue spaces. Known as edema. Describe the location of the Edema if the left side of the heart fails, compared to the location of Edema if the right side of the heart fails

if the left side of the heart fails edema would occur in the lower extremities of the body. If there is right side heart failure then edema would occur in the pulmonary region of the body

If the heart receives more sympathetic stimulation than parasympathetic stimulation, the heart will

increase its rate and force of contraction

Situation of the heart via the sympathetic nerves would

increase the force of ventricular contraction

In response to increased activity, the heart would be called upon to ___ the amount of blood pumped, and this would be caused by signals from ____ fibers.

increase; sympathetic

Which of the following factors would cause an increase in heart rate? increased parasympathetic stimulation stimulation of baroreceptors in the aorta increased epinephrine release from the adrenal medulla increased production of atrial natriuretic factor vagal stimulation

increased epinephrine release from the adrenal medulla

Coronary artery disease can diminish myocardial blood flow resulting in the death of myocardial cells. This condition is known as a myocardial

infarction

Coronary artery disease can diminish myocardial blood flow resulting in the death of myocardial cells. This condition is known as a myocardial attack. angina. necrosis. cirrhosis. infarction.

infarction.

Any factor that causes a change in heart contractility is called

inotrope Feedback: "Ino" mean fiber, and refers in this case to muscle fiber length. Heart contractility results from changes in fiber length.

Which structure is present in cardiac muscle tissue but NOT skeletal muscle tissue?

intercalated discs

The anterior and posterior interventricular sulci mark the position of which internal heart structure?

interventricular septum

All of the following regarding the apex of the heart is true

is part of the left ventricle wall, points inferiorly and laterally, is at the approximate level of the 5th intercostal space

The endocardium

is the smooth inner lining of the heart chambers

Blood does not enter or leave the ventricles during the period called

isovolumic contraction

How does a drug that increases the length of time required for the repolarization of pacemaker cells affect the heart rate?

it would decrease the heart rate because the pacemaker would generate fewer action potentials per minute

Caffeine has effects on conducting cells and contractile cells that are similar to those of NE. What effect would drinking large amounts of caffeinated drinks have on the heart?

it would increase the heart rate because it increases the rate at which the cells depolarize

If the cardioinhibitory center of the medulla onbongota were damaged, which part of the autonomic nervous system would be affected, and how would the heart be influenced?

it would reduce parasympathetic action potentials to the heart which would increase the heart rate

Myocardium

layer composed of cardiac muscle

An incompetent mitral valve may cause blood to back up into the

left atrium

An incompetent mitral valve may cause blood to back up into the Select one: a. coronary circulation. b. left atrium. c. left ventricle. d. aorta. e. right atrium.

left atrium

Blood in the pulmonary veins returns to the right atrium. left atrium. right ventricle. left ventricle. coronary sinus.

left atrium.

The anterior interventricular artery is a branch of the

left coronary artery

Obstruction of the ___________ will cause a more severe myocardial infarction (MI) than the obstruction of any of the others.

left coronary artery (LCA)

Which chamber of the heart has to work the hardest (pump against the highest pressure)?

left ventricle

endocardium

lining of the heart chambers

Mediastinum

location of the heart in the thorax

The serous fluid within the pericardial cavity works to

lubricate the membranes of the serous pericardium.

Damage to which of the following parts of the brain would cause the body to have less control over cardiac activity?

medulla oblongata

The cardioregulatory center of the brain is located in the

medulla oblongata

The cardioregulatory center of the brain is located in the hypothalamus. medulla oblongata. cerebellum. cerebrum. diencephalons.

medulla oblongata.

parietal pericardium

membrane outside of v pericardium

The trabeculae carneae in the left ventricle are ____________ in the right ventricle.

more prominent than

The ________________ performs the work of the heart.

myocardium

The muscle layer of the heart, whose function is to act as the pump for the cardiovascular system is the

myocardium

Which of the following layers forms the bulk of the heart wall

myocardium

Which of the following layers forms the bulk of the heart wall?

myocardium

The layer of the heart wall composed of cardiac muscle tissue is the

myocardium.

Is the heart always pumping blood when pressure in the left ventricle is rising?

no when it is rising the heart is contracting but no blood is leaving

In the cardiac cycle, a. all four chambers of the heart are in systole at the same time. b. the two atria relax while the two ventricles contract. c. the right atrium and the right ventricle contract simultaneously. d. all four chambers of the heart contract at the same time. e. the left atrium contracts before the right atrium.

not a

During the isovolumetric contraction period of the cardiac cycle, a. AV and semilunar valves are closed. b. the atria are contracted. c. pressure in the ventricles decreases. d. ventricular volume increases. e. blood is pumped into the large arteries.

not d

Afterload is a. the arterial pressure that the ventricles must overcome to eject blood. b. the name given to an increase in end-diastolic volume. c. another name for venous return. d. the amount cardiac output must increase during exercise. e. the extent to which ventricular walls are stretched.

not e

Within normal limits, an increase in preload leads to a. a decrease in cardiac output and force of left ventricular contraction. b. a decrease in stroke volume and heart rate. c. an increase in cardiac output and force of left ventricular contraction. d. a decrease in cardiac output and an increase in the force of left ventricular contraction. e. an increase in cardiac output and a decrease in force of left ventricular contraction.

not e

The plateau phase seen during the action potential of a cardiac muscle cell is due to the

opening of calcium slow channels

inferior vena cava

opens into the posterior and inferior portion of the right atrium and carries blood to the right atrium from the trunk, viscera, and lower limbs

The specialized area of the myocardium that acts to anchor the chordae tendineae is the

papillary muscle.

What is the name of the extensions of the ventricular myocardium that prevent the valves from opening into the atria?

papillary muscles

The pericardial sac is lined with fibrous pericardium. parietal pericardium. visceral pericardium. myocardium. epicardium.

parietal pericardium.

Which of the following pairs is mismatched?

pectinate muscles - muscles that close valves

Which of the following pairs is mismatched? endocardium - covers the inner surfaces of the heart myocardium - cardiac muscle trabeculae carneae - interior walls of ventricles pectinate muscles - muscles that close valves chordae tendineae - connective tissue strings that connect to cusps of valves

pectinate muscles - muscles that close valves

Between the parietal pericardium and the visceral pericardium is the

pericardial cavity containing pericardial fluid

The membranous covering of the heart is the _________, which includes a loosely fitting sac composed of an inner ________ and an outer _________.

pericardium; parietal pericardium; fibrous pericardium

The heart valves

permit the passage of blood in one direction.

Which of the following phrases would apply to cardiac muscle cells?

possess special cell-to-cell contacts called intercalated discs

What occurs first in the conducting system of the heart?

prepotential

During ventricular systole

pressure in the ventricles eventually exceeds pressure in the arteries and the semilunar valves open

Contraction of the papillary muscles would

prevent the AV valves from protruding into the atria

Contraction of the papillary muscles would Select one: a. cause the atria to eject their contents into the ventricles. b. open the semilunar valves. c. prevent the AV valves from protruding into the atria. d. eject blood from the ventricles. e. close the semilunar valves.

prevent the AV valves from protruding into the atria

The chordae tendineae

prevent the atrioventricular valve cusps from prolapsing into the atria when the ventricles contract

The long refractory period observed in cardiac muscle

prevents tetanic contractions of the cardiac muscle

The long refractory period observed in cardiac muscle Select one: a. prevents an increase in heart rate. b. prevents tetanic contractions of the cardiac muscle. c. ensures that the heart has adequate time to contract. d. prevents the heart rate from slowing down. e. prolongs depolarization of the cardiac muscle.

prevents tetanic contractions of the cardiac muscle.

The long refractory period observed in cardiac muscle prolongs depolarization of the cardiac muscle. prevents tetanic contractions of the cardiac muscle. ensures that the heart has adequate time to contract. prevents the heart rate from slowing down. prevents an increase in heart rate.

prevents tetanic contractions of the cardiac muscle.

coronary arteries

provide nutrient blood to the heart muscle

Which of the following is NOT a function of the heart? providing a location for gas exchange between oxygen and carbon dioxide regulating blood supply to tissues depending on need generating blood pressure through contraction routing blood to either the pulmonary or systemic circulations

providing a location for gas exchange between oxygen and carbon dioxide

The right side of the heart receives blood from the body and pumps through _________ circulation to the lungs. Select one: a. pulmonary b. systemic c. hepatic d. peripheral

pulmonary

The right side of the heart receives blood from the body and pumps through _________ circulation to the lungs. hepatic pulmonary peripheral systemic

pulmonary

semilunar valves

pulmonary and aortic valves

Which vessels transport blood to the right and left lungs? aorta right atrium pulmonary trunk pulmonary arteries pulmonary veins

pulmonary arteries

The right side of the heart acts as a pump for the

pulmonary circulation

The valve located between the right ventricle and the pulmonary trunk is the aortic semilunar valve. pulmonary semilunar valve. tricuspid valve. mitral valve. bicuspid valve.

pulmonary semilunar valve.

Damage to the semilunar valve of the right ventricle would affect blood flow into which vessel?

pulmonary trunk

Pressure in the right ventricle must exceed pressure in the ____ before the right ventricle can eject blood. Select one: a. superior vena cava b. coronary sinus c. pulmonary trunk d. aorta e. pulmonary veins.

pulmonary trunk

Pressure in the right ventricle must exceed pressure in the ______ before the right ventricle can eject blood

pulmonary trunk

These vessels open directly into the left atrium

pulmonary veins

The function of the pericardial fluid is to

reduce friction between the pericardial membranes

anterior and posterior interventricular sulcus

shallow depressions that mark the boundary between the left and right ventricles

Which structure of the heart is known as the cardiac pacemaker or the natural pacemaker?

sinoatrial node

pericardial cavity

space between the visceral and parietal pericardium

End-diastolic volume minus end-systolic volume is equal to

stroke volume

The volume of blood pumped during each cardiac cycle is the

stroke volume

The volume of blood pumped during each cardiac cycle is the stroke volume. cardiac output. cardiac reserve. end-systolic volume. end-diastolic volume.

stroke volume.

After entering the right atrium, the furthest a red blood cell will travel is the

superior vena cava.

Contraction of a ventricular chamber is called

systole

What occurs during the time between the first heart sound and the second heart sound?

systole

Provide the technical terms for heart contraction and heart relaxation.

systole and diastole

Contraction of the ventricles is referred to as ventricular systole. diastole. fibrillation. ischemia. depolarization.

systole.

What abnormal heart rhythm could be caused by an elevated body temperature, excessive sympathetic stimulation, or toxic conditions? bradycardia atrial fibrillation second-degree AV node block tachycardia

tachycardia

Which of the following will depolarize immediately after the AV node depolarizes?

the AV bundle

You are normally unable to see a waveform indicating repolarization of the atria on an ECG because

the QRS complex is such a large electrical event it hides the waveform

Define automaticity.

the ability of the cardiac muscle tissue to contract without neural or hormone stimulation

Define cardiac output.

the amount of blood pumped by the left ventricle in one minute

With respect to the effect on cardiac output, the term preload refers to

the amount of tension developed in the myocardium before it contracts

The cardiac electrical impulse normally begins spontaneously in the SA node because

the area depolarizes more rapidly than any other portion of the conduction system

Afterload is

the arterial pressure that the ventricles must overcome to eject blood

The right atrium receives blood from Select one: a. the heart. b. the lungs and the heart. c. the body and the heart. d. the lungs and the body.

the body and the heart

The innermost lining of the heart wall is

the endocardium.

A stab wound into the heart can result in cardiac tamponade. This means

the heart is compressed by blood in the pericardial sac

Increased vagal stimulation would cause

the heart rate to decrease

If the cells of the SA node did not function, how would the heart rate be affected?

the heart would beat slower and the av node would be the pacemaker

E.Z. Goen is admitted to the cardiac unit with a diagnosis of endocarditis. When E.Z. asks the nurse where the infection is located, the nurse replies that the infection is in

the inner lining of the heart

E.Z. Goen is admitted to the cardiac unit with a diagnosis of endocarditis. When E.Z. asks the nurse where the infection is located, the nurse replies that the infection is in

the inner lining of the heart.

interatrial septum

the muscle that separates the atria

interventricular septum

the muscle that separates the ventricles

Depolarization of a cardiac muscle cell occurs as the result of

the opening of voltage-gated sodium channels

Pericardial fluid is found between

the parietal and visceral membranes.

The period of isovolumic contraction is immediately followed by

the period of ejection

The period of isovolumetric contraction is immediately followed by the period of ejection. AV node depolarization. passive ventricular filling. atrial contraction. isovolumetric relaxation.

the period of ejection.

which valves close when the cusps fill with blood

the pulmonary and the Aortic valves (semilunar valves) close when the cusps fill with blood

mediastinum

the region between the two pleural cavities

superior vena cava

the vein that opend into the posterior and superior portion of the right atrium and delivers blood from the head, neck, upper limbs, and chest

What is the function of the heart valves?

to prevent the backflow of blood

fibrous pericardium

tough outer membrane made out of fibrous connective tissue that stabilizes the heart

Stroke volume and heart rate may increase cardiac output to 40 L/min in

trained athletes

atrioventricular valves

tricuspid and mitral valves

Which of the following lists the valves in the order through which the blood flows from the vena cava through the heart? a. tricuspid, pulmonary semilunar, bicuspid, aortic semilunar b. mitral, pulmonary semilunar, bicuspid, aortic semilunar c. aortic semilunar, pulmonary semilunar, tricuspid, bicuspid d. bicuspid, aortic semilunar, tricuspid, pulmonary semilunar

tricuspid, pulmonary semilunar, bicuspid, aortic semilunar

Typically, there are __________ papillary muscles that project from the wall of the left ventricle and attach to the chordae tendineae that support the left AV valve

two

coronary sinus

vein that opens into the right atrium inferior to the connection with the superior vena cava

The coronary sinus is a(n) _____ located in the _____.

vein; posterior atrioventricular sulcus

The higher the __________, the greater the cardiac output.

venous return

Damage to the cells of the AV bundle would prevent the cardiac impulse from reaching the

ventricles

semilunar valves prevent back flow into the

ventricles

The QRS complex of the ECG appears as the

ventricles depolarize

Pressure in the ventricles would be highest during

ventricular systole

capillaries

vessels that connect arteries and veins

The first and second heart sounds are most directly related to

vibrations that occur when the valves close

The epicardium is another name for the

visceral layer of the serous pericardium.

The pericardial layer that is in contact with the heart is the

visceral pericardium

epicardium

visceral pericardium

Which two layers are the most similar in tissue structure?

visceral pericardium and parietal pericardium

The depolarization phase of the cardiac muscle action potential occurs when Select one: a. voltage-gated K+ ion channels open. b. voltage-gated Na+ ion channels open. c. voltage-gated Ca2+ ion channels open. d. voltage-gated Ca+ and Na+ion channels open

voltage-gated Na+ ion channels open

A blood clot in the circumflex artery would cause a myocardial infarction in part of the

walls of the left atrium and posterior left ventricle

Trace a drop of blood through the heart and lungs

(Pulmonary circuit = Right atrium, tricuspid valve, right ventricle, pulmonary valve, pulmonary trunk, pulmonary arteries, pulmonary capillaries, pulmonary veins,) ((systemic circuit) = left atrium,mitral valve, left ventricle, aortic valve, aorta)

A patients cardiac output at rest is 5 L/min. When she is exercising strenuously it is 20 L/min. What is her cardiac reserve?

15 L/min

Given these valves: 1. aortic semilunar valve 2. bicuspid valve 3. pulmonary semilunar valve 4. tricuspid valve. Arrange them in the order in which an erythrocyte would pass through them after returning to the heart from the left arm.

4, 3, 2, 1

The normal rate of spontaneous depolarization of the AV node is Select one: a. 70 - 80 per minute b. 40 - 60 per minute c. over 100 per minute d. 20 - 40 per minute

40 - 60 per minute

The normal rate of spontaneous depolarization of AV nodal cells is

40 to 60 per minute

If the heart rate for a patient is 80 bpm, and her stroke volume is 70 mL/beat, then her cardiac output is

5600 mL/min

The volume of blood ejected during ventricular systole is roughly _______ of end-diastolic volume.

60%

The action potentials are slowed at the AV node to allow the a. atria to begin their contraction b. pacemaker to reset for the next beat c. atria to complete their contraction d. ventricles to repolarize e. ventricles to completely empty of blood

?? c. atria to complete their contraction

Depolarization if a cardiac muscle cell occurs as the result of a. a decrease in permeability of the cell membrane to sodium b. the opening of voltage gated potassium channels c. the opening of voltage gated sodium channels and voltage gated calcium channels d. the closure of the voltage gated sodium channels e. the closure of voltage gates calcium channels

??? c. the opening of voltage gated sodium channels and voltage gated calcium channels

15. Which of the following statements is true? a. In one day, more fluid exits the capillary through filtration than enters through reabsorption. b. In one day, approximately 35 mm of blood are filtered and 7 mm are reabsorbed. c. In one day, the capillaries of the lymphatic system absorb about 20.4 liters of fluid. d. None of the above are true.

18. The cardiovascular centers are located in which area of the brain? a. medulla oblongata b. pons c. mesencephalon (midbrain) d. cerebrum

19. A form of circulatory shock common in young children with severe diarrhea or vomiting is ________. a. hypovolemic shock b. anaphylactic shock c. obstructive shock d. hemorrhagic shock

20. What happens to preload when there is venous constriction in the veins? a. It increases. b. It decreases. c. It remains constant. d. There is no way to predict.

24. The hepatic portal system delivers blood from the digestive organs to the ________. a. liver b. hypothalamus c. spleen d. left atrium

25. Which primitive area of the heart will give rise to the right ventricle? a. bulbus cordis b. primitive ventricle c. sinus venosus d. truncus arteriosus

3. The endothelium is found in the ________. a. tunica intima b. tunica media c. tunica externa d. lumen

3. Which valve separates the left atrium from the left ventricle? a. mitral b. tricuspid c. pulmonary d. aortic

4. Which of the following lists the valves in the order through which the blood flows from the vena cava through the heart? a. tricuspid, pulmonary semilunar, bicuspid, aortic semilunar b. mitral, pulmonary semilunar, bicuspid, aortic semilunar c. aortic semilunar, pulmonary semilunar, tricuspid, bicuspid d. bicuspid, aortic semilunar, tricuspid, pulmonary semilunar

9. A healthy elastic artery ________. a. is compliant b. reduces blood flow c. is a resistance artery d. has a thin wall and irregular lumen

How would you distinguish the structure of cardiac muscle from that of skeletal muscle

A distinguishable feature of cardiac muscle is the presence of intercalated discs. In addition cardiac muscle had a branched design, uninucleated and not prominently striated as opposed to skeletal muscle which is prominently striated and multinucleated.

A proximal LAD lesion is a blockage in the left anterior descending artery, also known as the anterior interventricular artery. Explain why a heart attack caused by an obstruction of this artery is sometimes referred to as the " widow maker" Heart attack

A widow maker heart attack gets its name because of how deadly it is. because if the LAD is blocked then it can't supply the myocardium, which then can't supply blood to the left ventricle. The left ventricle then can't carry blood into the body which doesn't allow the body to survive.

The plateau phase of the cardiac contractile cell action potential is caused by

A) Ca2+ inflow Feedback: The plateau phase slows repolarization by increasing the number of positive ions in the cell.

Calcium is needed for contraction in both skeletal muscle and cardiac muscle. However there are some differences in where it comes from and what it does. Which of these choices correctly describes how calcium works in cardiac muscle cells? A) Extracellular Ca2+ diffuses into the cardiac muscle cells, binds to Ca2+ channels in the sarcoplasmic reticulum and causes Ca2+ release into the cytosol. B) Extracellular Ca2+ diffuses into the cardiac muscle cells, binds to troponin and initiates contraction. C) Ca2+ from the sarcoplasmic reticulum diffuses out of the cell, causing the plateau phase of the action potential. D) Ca2+ from the sarcoplasmic reticulum diffuses out of the cell, causing repolarization.

A) Extracellular Ca2+ diffuses into the cardiac muscle cells, binds to Ca2+ channels in the sarcoplasmic reticulum and causes Ca2+ release into the cytosol. Feedback: In cardiac muscle cells, extracellular Ca2+ has a different job than the Ca2+ from the sarcoplasmic reticulum. The extracellular Ca2+ ions are involved in action potential formation. The ions from the sarcoplasmic reticulum are involved in the contraction mechanism.

In an ECG taken from a person who has no SA node activity, which component will not appear?

A) P wave Feedback: The initial wave of an ECG tracing is the P wave, which corresponds to an action potential formed by the SA node.

What is not a positive chronotrope?

A) acetylcholine

Energy for contraction of myocardial cells comes primarily from

A) aerobic respiration in the mitochondria. Feedback: The energy demands of the myocardium are very high, therefore cardiac cells require the full ATP production provided by aerobic respiration.

In the cardiac conduction system, junctional fibers connect the

A) atrial syncytium to the AV node.

The amount of blood in the ventricles just before they contract is called the

A) end diastolic volume Feedback: The end of diastole coincides with the beginning of systole. At the end of ventricular diastole, the ventricles are as full as they are going to be. At the end of ventricular systole, the ventricles are as empty as they are going to be. The difference between EDV and ESV is the stroke volume. Cardiac output is defined as SV times beats per minute.

The atria are electrically isolated from the ventricles by the

A) fibrous skeleton Feedback: The fibrous skeleton of the heart is composed of collagen fibers. It electrically isolates the atria from the ventricles, and serves as the attachment site of the valves and muscle.

Which component of a myocardial cell allows it to electrically stimulate adjoining cells?

A) gap junctions Feedback: The only way for a cell to electrically stimulate (as opposed to chemical stimulation) an adjoining cells is to allow ions to pass directly from the cytoplasm of one cell to the next.

Intercalated discs include these structures: A) gap junctions, desmosomes, interdigitating folds B) gap junctions, tight junctions, t-tubules C) gap junctions, desmosomes, t-tubules D) sarcoplasmic reticulum, interdigitating folds

A) gap junctions, desmosomes, interdigitating folds Feedback: Everything at an intercalated disc involves holding two myocardial cells together or allowing them to communicate. T-tubules and sarcoplasmic reticula are located within muscle cells, not between them.

What ionic imbalance would decrease the strength of cardiac muscle contraction?

A) hypocalcemia Feedback: Calcium ions are needed for both cardiac action potential formation and for the mechanical events of cardiac muscle contraction.

The "skeleton" of the heart provides attachment for?

A) provides attachment for the heart valves and cardiac muscle Feedback: The fibrous skeleton of the heart is composed of collagen fibers. It electrically isolates the atria from the ventricles, and serves as the attachment site of the valves and muscle.

The function of the pericardial fluid is to

A) reduce friction between the pericardial membranes

Which of the following commonly increases with age? A) size of the left ventricle B) size of the right ventricle C) heart rate D) flexibility of heart valves

A) size of the left ventricle Feedback: A gradual increase in aortic pressure caused by aging makes it harder for the left ventricle to eject blood, causing it to increase its size to increase its strength.

The cells of the heart's normal pacemaker spontaneously generate electrical signals about_____ to ______ times per minute.

A) spontaneously generate electrical signals about 70 to 80 times per minute. Feedback: The SA node has the fastest depolarization/repolarization rate, and is called the pacemaker because it originates the cardiac impulse.

The coronary sinus is a(n) ______ located in the ________.

A) vein; posterior atrioventricular sulcus Feedback: The coronary sinus is located between the atria and the ventricles on the right side of the heart. It drains the veins of the heart into the right atrium.

When ventricular pressure exceeds atrial pressure, the: A. AV valves close. B. atria pump blood into the ventricles. C. ventricle is in diastole. D. blood is pumped into the atrium.

A. AV valves close

Blockage of the following would primarily damage the left ventricle: A.Circumflex artery B. Pulmonary artery C. Right marginal artery D. Coronary sinus artery

A. Circumflex artery

Within normal limits, an increase in preload leads to: A. an increase in cardiac output and force of left ventricular contraction. B. a decrease in cardiac output and force of left ventricular contraction. C. an increase in cardiac output and a decrease in force of left ventricular contraction. D. a decrease in cardiac output and an increase in force of left ventricular contraction.

A. an increase in cardiac output and force of left ventricular contraction

During the ejection phase of the cardiac cycle, blood enters the: A. aorta. B. coronary sinus. C. pulmonary vein. D. superior vena cava.

A. aorta

Atrioventricular valves prevent backflow of blood into the _____; semilunar valves prevent backflow into the ______

A. atria; ventricle

Match the drug with its effects. A. binds to epinephrine receptors B. prevents clot formation C. can reduce calcium diffusion rate into myocardial cells D. frequently given to people with restricted coronary blood flow in order to reduce preload E. used to treat high blood pressure beta blocking agent

A. binds to epinephrine receptors

The AV valve that is located on the same side of the heart as the origin of the aorta is the: A. mitral valve B. tricuspid valve C. aortic semilunar valve D. pulmonary semilunar valve

A. mitral valve

Contraction of the ventricles is referred to as ventricular: A. systole. B. diastole. C. fibrillation. D. ischemia.

A. systole

Increased vagal stimulation would cause: A. the heart rate to decrease B. the heart rate to increase C. no change in heart rate

A. the heart rate to decrease

Increased vagal stimulation would cause: A. the heart rate to decrease. B. the heart rate to increase. C. no change in heart rate.

A. the heart rate to decrease

The period of isovolumetric contraction is followed by: A. the period of ejection. B. AV node depolarization. C. passive ventricular filling. D. atrial contraction.

A. the period of ejection

Lowered extracellular potassium levels will lower heart rate because: A. the resting membrane potential is hyperpolarized. B. ectopic action potentials occur. C. action potential amplitude declines. D. more sodium channels open.

A. the resting membrane potential is hyperpolarized

During the isovolumetric contraction period of the cardiac cycle, ___ and _____ valves are closed

AV and semilunar

During the isovolumic contraction period of the cardiac cycle,

AV and semilunar valves are closed

If the SA node is damaged, which part of the heart is most likely to take over as a pacemaker? Select one: a. Purkinje fibers b. AV nodal cells c. ventricular myocardial cells d. atrial myocardial cells

AV nodal cells

If the SA node is damaged, which part of the heart is most likely to take over as pacemaker?

AV nodal cells

The group of modified cardiac muscle cells that delays action potentials between the atria and the atrioventricular bundle is called the

AV node

alternate names for the right atrioventricular valve

AV valve, RAT, tricuspid

alternate names fot the left atrioventricular valve

AV valve, bicuspid valve, LAMB, mitral valve

The force the heart must overcome to pump blood is known as ________. a. preload b. afterload c. cardiac output d. stroke volume

Afterload

Which of the following is a function of the heart skeleton? Select one: a. Provides electrical insulation between the atria and ventricles. b. Provides a rigid site for cardiac muscle attachment. c. Supplies support and reinforcement for the valves. d. All of the choices are functions of the heart skeleton.

All of the choices are functions of the heart skeleton.

Which of the following is a function of the heart skeleton? Provides electrical insulation between the atria and ventricles. Supplies support and reinforcement for the valves. Provides a rigid site for cardiac muscle attachment. All of the choices are functions of the heart skeleton.

All of the choices are functions of the heart skeleton.

What is the importance of the delay in the action potential in the AV node?

Allows an action potential to reach the left atrium so both atria contract together

Which blood vessel carries blood from the left ventricle?

Aorta

As soon as left ventricular pressure exceeds the pressure in the aorta, the ____ ____ valve opens

Aortic semilunar

The P wave of an ECG indicates:

Atrial depolarization

Most blood enters the ventricle during ________. a. atrial systole b. atrial diastole c. ventricular systole d. isovolumic contraction

Atrial diastole

In which septum is it normal to find openings in the adult? a. interatrial septum b. interventricular septum c. atrioventricular septum d. all of the above

Atrioventricularr

10. Which of the following statements is true? a. The longer the vessel, the lower the resistance and the greater the flow. b. As blood volume decreases, blood pressure and blood flow also decrease. c. Increased viscosity increases blood flow. d. All of the above are true.

13. Hydrostatic pressure is ________. a. greater than colloid osmotic pressure at the venous end of the capillary bed b. the pressure exerted by fluid in an enclosed space c. about zero at the midpoint of a capillary bed d. all of the above

14. Most blood enters the ventricle during ________. a. atrial systole b. atrial diastole c. ventricular systole d. isovolumic contraction

16. Ventricular relaxation immediately follows ________. a. atrial depolarization b. ventricular repolarization c. ventricular depolarization d. atrial repolarization

17. The force the heart must overcome to pump blood is known as ________. a. preload b. afterload c. cardiac output d. stroke volume

19. In a healthy young adult, what happens to cardiac output when heart rate increases above 160 bpm? a. It increases. b. It decreases. c. It remains constant. d. There is no way to predict.

20. The coronary arteries branch off of the ________. a. aortic valve b. ascending aorta c. aortic arch d. thoracic aorta

26. Which of the following statements is true? a. Two umbilical veins carry oxygen-depleted blood from the fetal circulation to the placenta. b. One umbilical vein carries oxygen-rich blood from the placenta to the fetal heart. c. Two umbilical arteries carry oxygen-depleted blood to the fetal lungs. d. None of the above are true.

6. The ________ layer secretes chemicals that help to regulate ionic environments and strength of contraction and serve as powerful vasoconstrictors. a. pericardial sac b. endocardium c. myocardium d. epicardium

6. Which of the following best describes veins? a. thick walled, small lumens, low pressure, lack valves b. thin walled, large lumens, low pressure, have valves c. thin walled, small lumens, high pressure, have valves d. thick walled, large lumens, high pressure, lack valves

7. The myocardium would be the thickest in the ________. a. left atrium b. left ventricle c. right atrium d. right ventricle

8. In a blood pressure measurement of 110/70, the number 70 is the ________. a. systolic pressure b. diastolic pressure c. pulse pressure d. mean arterial pressure

What is the correct sequence of the cardiac conduction system?

B) SA node, AV node, AV bundle, Purkinje fibers Feedback: The SA node has the fastest depolarization/repolarization rate, and is called the pacemaker because it originates the cardiac impulse. The AV node is located at the junction of the interatrial and atrioventricular septa. The AV bundle exits the AV node and enters the interventricular septum. The Purkinje fibers are located in the ventricular myocardium and terminate in the papillary muscles.

Of the amount of blood entering the ventricles before they contract about 70% come in before?

B) about 70% comes in before atrial contraction. Feedback: Passive filling occurs during the atrial and ventricular diastole between beats.

An auricle is an extension of?

B) an extension of the atrial wall Feedback: "Auricle" means ear-like, and refers to flap-like appearance of the atrium when not filled with blood.

Conduction of the cardiac impulse is slowed as it passes through the AV node. This allows time for the atria

B) atria to contract completely before the ventricles start to contract. Feedback: In order to maintain one-way flow of blood through the heart, it is important that the atria be relaxing before the ventricles begin to contract.

An obstruction in the pulmonary trunk would prevent blood from

B) picking up oxygen in the lungs Feedback: A trunk is a large vessel. The pulmonary trunk is a large artery that carries blood from the heart toward the lungs.

Ventricular contraction begins at the: A. AV bundle. B. apex of the heart. C. base of the heart. D. superior portion of the interventricular septum.

B. Apex of the heart

Use the following key to mark the most correct answer. A. Choose A if the first item is greater than the second item. B. Choose B if the first item is less than the second item. C. Choose C if the first item is equal or nearly equal to the second item. (1) thickness of the right ventricular wall; (2) thickness of the left ventricular wall

B. Choose B if the first item is less than the second item

Use the following key to mark the most correct answer. A. Choose A if the first item is greater than the second item. B. Choose B if the first item is less than the second item. C. Choose C if the first item is equal or nearly equal to the second item. (1) length of the refractory period in skeletal muscle cells; (2) length of the refractory period in cardiac muscle cells

B. Choose B if the first item is less than the second item.

The skeleton of the heart: A. helps to support the coronary arteries B. anchor the cardiac muscle fibers C. contain osseous tissue D. prevents the back flow of blood in the heart

B. anchor the cardiac muscle fibers

Blood vessels enter and exit from the ______ of the heart A. apex B. base C. auricles D. trigone

B. base

Which of the following will increase end-diastolic volume? A. vasodilation B. contracting the muscles in the legs C. increasing the heart rate D. decreasing venous return

B. contracting the muscles in the legs

An incomplete mitral valve may cause blood to back up into the: A. aorta B. left atrium C. left ventricle D. coronary circulation

B. left atrium

B. prevents clot formation

Afterload is: A. the name given to an increase in end-diastolic volume. B. the arterial pressure that the ventricles must overcome to eject blood. C. the amount cardiac output must increase during exercise. D. another name for venous return.

B. the arterial pressure that the ventricles must overcome to eject blood

An increase in extracellular calcium generally increases: A. the heart rate. B. the force of contraction. C. autonomic stimulation of the heart. D. sodium channel opening.

B. the force of contraction

In the cardiac cycle, A. the right atrium and the right ventricle contract simultaneously. B. the two atria relax while the two ventricles contract. C. the left atrium contracts before the right atrium. D. all four chambers contract at the same time.

B. the two atria relax while the two ventricles contract

Septum

Barrier

Why is the left ventricle more muscular than the right ventricle?

Because the left ventricle has to be able to pump blood through the whole body and the right ventricle only has to send it to the lungs

Baroreceptor reflexes are triggered by increased:

Blood pressure

What is the end systolic pressure-volume relationship and how is it shown?

1. A can can be drawn through the end systolic pressure points of pressure volume loops. 2. The line corresponds to the total tension line determined in isolated muscle preparations and is important in describing the contractile properties of the intact heart.

What effects does an increase in afterload result in?

1. A decrease in the velocity of shortening. 2. A decrease in the extent of shortening. 3. A decrease in the stroke volume.

What is a common misconception of Afterload and it's components?

1. Afterload is the tension in the wall of the ehart during systole, where factors such as aortic pressure will determine the pressure needed to allow blood to be ejected from the heart and thus can be used as a measure to assess changes in afterload. 2. Thus, one should not confuse what contributes to increasing or decreasing the afterload with the definition of afterload.

During the Cardiac Cycle, what is considered the afterload?

1. Afterload is the wall stress (or tension) borne by the myofibrils in the ventricle during contraction (systole). 2. The wall stress is directly proportional to the pressure in the ventricles. 3. Thus, the pressure in the ventricle is a measure of afterload.

By examining the pressure-volume loop, what is the relationship between the extent of shortening and afterload can be seen and how is this presented in terms of stroke volume?

1. An inverse relationship exists between the extent of shortening and afterload. 2. This is shown by a decrease in stroke volume when afterload is increased and, conversely, by an increase in stroke volume when afterload is decreased.

When would a purely isovolumetric contraction occur in the heart?

1. An isovolumetric contraction will result if the pressure generated by the heart cannot overcome aortic pressure. 2. Seen only experimentally.

What are the different factors that can be used to asses changes in the Afterload?

1. Aortic Pressure (if no valve problems present). 2. Systemic Vascular Resistance (can increase the pressure working against it). 3. Outflow tract resistance. 4. Systolic ventricular pressure.

What is the relationship between compliance of the ventricles and their volume/pressure and what effect does it have on the heart?

1. At low volumes, the resting ventricle has high compliance. The addition of large volumes of blood produce small changes in pressure. 2. At higher volumes, the compliance of the heart decreases. The smaller volumes result in a large change in pressure. 3. This decrease in compliance at higher volumes helps maintain the myofilament length on the ascending limb of the active tension curve.

On a Velocity/Force graph, what key feature shows that the preload is affected as compared to the normal levels?

1. The y-intercept on the velocity scale will remain the same, but you are going to have a greater velocity at any given afterload overall.

What is the relationship between preload and stroke volume?

1. There is a direct relationship between the extent of shortening and preload. 2. This is shown by an increase in stroke volume when preload is increased (shortening increased). 3. Conversely, by a decrease in stroke volume when preload is decreased (shortening decreased).

What are the factors that will affect Preload?

1. Venous Return. 2. Atrial Pressure (dictates delta P during filling). 3. End diastolic ventricular pressure and volume.

On a graph of pressure vs volume, what is the passive filling curve?

1. We find that as volume is progressively added to the resting ventricle, a nonlinear relationship between each increment of volume and pressure is produced.

The myocardium is

Both the major portion of the heart and largely cardiac muscle tissue.

Which primitive area of the heart will give rise to the right ventricle? a. bulbus cordis b. primitive ventricle c. sinus venosus d. truncus arteriosus

Bulbus cordis

15. The first heart sound represents which portion of the cardiac cycle? a. atrial systole b. ventricular systole c. closing of the atrioventricular valves d. closing of the semilunar valves

17. In the renin-angiotensin-aldosterone mechanism, ________. a. decreased blood pressure prompts the release of renin from the liver b. aldosterone prompts increased urine output c. aldosterone prompts the kidneys to reabsorb sodium d. all of the above

18. In the myogenic response, ________. a. muscle contraction promotes venous return to the heart b. ventricular contraction strength is decreased c. vascular smooth muscle responds to stretch d. endothelins dilate muscular arteries

21. Which of the following is a positive inotrope? a. Na+ b. K+ c. Ca2+ d. both Na+ and K+

21. Which of the following statements is true? a. The left and right common carotid arteries both branch off of the brachiocephalic trunk. b. The brachial artery is the distal branch of the axillary artery. c. The radial and ulnar arteries join to form the palmar arch. d. All of the above are true.

22. Arteries serving the stomach, pancreas, and liver all branch from the ________. a. superior mesenteric artery b. inferior mesenteric artery c. celiac trunk d. splenic artery

23. Of the three germ layers that give rise to all adult tissues and organs, which gives rise to the heart? a. ectoderm b. endoderm c. mesoderm d. placenta

27. The ductus venosus is a shunt that allows ________. a. fetal blood to flow from the right atrium to the left atrium b. fetal blood to flow from the right ventricle to the left ventricle c. most freshly oxygenated blood to flow into the fetal heart d. most oxygen-depleted fetal blood to flow directly into the fetal pulmonary trunk

5. Closer to the heart, arteries would be expected to have a higher percentage of ________. a. endothelium b. smooth muscle fibers c. elastic fibers d. collagenous fibers

5. Which chamber initially receives blood from the systemic circuit? a. left atrium b. left ventricle c. right atrium d. right ventricle

7. An especially leaky type of capillary found in the liver and certain other tissues is called a ________. a. capillary bed b. fenestrated capillary c. sinusoid capillary d. metarteriole

9. Which of the following is unique to cardiac muscle cells? a. Only cardiac muscle contains a sarcoplasmic reticulum. b. Only cardiac muscle has gap junctions. c. Only cardiac muscle is capable of autorhythmicity d. Only cardiac muscle has a high concentration of mitochondria

The sinus rhythm of a normal adult heart would be about

C) 70 - 80 beats per minute.

What do skeletal muscle cells, cardiac autorhythmic cells, and cardiac contractile cells have in common?

C) In all three, repolarization is caused by K+ outflow Feedback: Ca2+ is involved in cardiac muscle cell potentials, but not in skeletal muscle cell potentials.

The coronary sulcus is a groove on the outside of the heart that marks the division between the

C) atria and ventricles Feedback: The coronary sulcus is also known as the atrioventricular sulcus.

In which choice must the first event occur before the second event for normal cardiac activity during one cardiac cycle? A) Purkinje cells depolarize; atrial myocardial cells contract B) ventricular cells contract; atrial cells contract C) atrioventricular valves close; semilunar valves open D) AV node depolarizes; SA node depolarizes

C) atrioventricular valves close; semilunar valves open

During the isovolumetric phase of the cardiac cycle both the atria and the ventricles are?

C) both atria and ventricles are relaxed Feedback: The isovolumetric phase occurs immediately after the T wave ends. The ventricles relax, but for a short period all the valves in the heart are closed, and no ventricular filling offers. Because the ventricular volume is not changing, this time is said to be isovolumetric (meaning "same volume").

Which structure is present in the cardiac muscle tissue but not skeletal muscle tissue? A) striations B) nuclei C) intercalated disks D) t-tubules

C) intercalated disks Feedback: Cardiac muscle cells are joined end-to-end, whereas skeletal muscle cells are not.

The heart valves prevent?

C) prevent blood from flowing backward through the heart. Feedback: The atrioventricular and semilunar valves are designed to maintain one-way flow of blood through the heart. The "lub-dup" heart sounds are caused by the closing of the valves.

The plateau phase of the cardiac myocardial cell potential prevents?

C) prevents tetanus, which would cease pumping action of the heart Feedback: The plateau phase lengthens the absolute refractory period, preventing a second impulse from forming before the contraction caused by the first has relaxed.

The pericardial cavity is between the

C) visceral pericardium and parietal pericardium Feedback: The pericardial cavity isolates the heart within the mediastinum.

Which two layers are the most similar in tissue structure? A) fibrous pericardium and visceral pericardium B) fibrous pericardium and endocardium C) visceral pericardium and parietal pericardium D) myocardium and endocardium

C) visceral pericardium and parietal pericardium Feedback: They are most similar because they are continuous with each other and are composed of the same kinds of tissues.

Baroreceptor reflexes: A. are triggered by increased blood osmolality B. correct changes in blood pH C. can change the heart rate D. are of minor importance in humans

C. can change the heart rate

The product of stroke volume and heart rate is known as: A. end-diastolic volume. B. end-systolic volume. C. cardiac output. D. ejection fraction.

C. cardiac output

Stimulation of the heart via the sympathetic nerves would: A. slow heart rate. B. decrease stroke volume. C. increase the force of ventricular contraction. D. increase end-diastolic volume.

C. increase the force of ventricular contraction

Pressure in the right ventricle must exceed the pressure in the ______ before the right ventricle can eject blood. A. superior vena cava B. coronary sinus C. pulmonary trunk D. aorta

C. pulmonary trunk

Which of the following is a positive inotrope? a. Na+ b. K+ c. Ca2+ d. both Na+ and K+

Ca2+

The plateau phase of the cardiac contractile cell action potential is caused by

Ca2+ inflow

The influx of which ion accounts for the plateau phase? a. sodium b. potassium c. chloride d. calcium

Calcium

The amount of blood pumped by each ventricle in one minute is referred to as ____________________.

Cardiac output

The two tubes that eventually fuse to form the heart are referred to as the ________. a. primitive heart tubes b. endocardial tubes c. cardiogenic region d. cardiogenic tubes

Cardiogenic tubes

What can baroreceptor reflexes do?

Change heart rate

The first heart sound represents which portion of the cardiac cycle? a. atrial systole b. ventricular systole c. closing of the atrioventricular valves d. closing of the semilunar valves

Closing of the atrioventricular valves

The plateau phase seen during the action potential of a cardiac muscle cell is due to what?

Continuing to have open calcium (Ca) channels

The great cardiac vein and middle cardiac vein empty into a venous cavity called:

Coronary sinus

10. The influx of which ion accounts for the plateau phase? a. sodium b. potassium c. chloride d. calcium

11. Slight vasodilation in an arteriole prompts a ________. a. slight increase in resistance b. huge increase in resistance c. slight decrease in resistance d. huge decrease in resistance

11. Which portion of the ECG corresponds to repolarization of the atria? a. P wave b. QRS complex c. T wave d. none of the above: atrial repolarization is masked by ventricular depolarization

12. Venoconstriction increases which of the following? a. blood pressure within the vein b. blood flow within the vein c. return of blood to the heart d. all of the above

12. Which component of the heart conduction system would have the slowest rate of firing? a. atrioventricular node b. atrioventricular bundle c. bundle branches d. Purkinje fibers

13. The cardiac cycle consists of a distinct relaxation and contraction phase. Which term is typically used to refer ventricular contraction while no blood is being ejected? a. systole b. diastole c. quiescent d. isovolumic contraction

14. Net filtration pressure is calculated by ________. a. adding the capillary hydrostatic pressure to the interstitial fluid hydrostatic pressure b. subtracting the fluid drained by the lymphatic vessels from the total fluid in the interstitial fluid c. adding the blood colloid osmotic pressure to the capillary hydrostatic pressure d. subtracting the blood colloid osmotic pressure from the capillary hydrostatic pressure

16. Clusters of neurons in the medulla oblongata that regulate blood pressure are known collectively as ________. a. baroreceptors b. angioreceptors c. the cardiomotor mechanism d. the cardiovascular center

2. Which of the following is not important in preventing backflow of blood? a. chordae tendineae b. papillary muscles c. AV valves d. endocardium

22. The earliest organ to form and begin function within the developing human is the ________. a. brain b. stomach c. lungs d. heart

23. The right and left brachiocephalic veins ________. a. drain blood from the right and left internal jugular veins b. drain blood from the right and left subclavian veins c. drain into the superior vena cava d. all of the above are true

24. The two tubes that eventually fuse to form the heart are referred to as the ________. a. primitive heart tubes b. endocardial tubes c. cardiogenic region d. cardiogenic tubes

25. Blood islands are ________. a. clusters of blood-filtering cells in the placenta b. masses of pluripotent stem cells scattered throughout the fetal bone marrow c. vascular tubes that give rise to the embryonic tubular heart d. masses of developing blood vessels and formed elements scattered throughout the embryonic disc

26. The pulmonary trunk and aorta are derived from which primitive heart structure? a. bulbus cordis b. primitive ventricle c. sinus venosus d. truncus arteriosus

4. Nervi vasorum control ________. a. vasoconstriction b. vasodilation c. capillary permeability d. both vasoconstriction and vasodilation

Which of the following is not associated with atrioventricular valves? A) chordae tendineae B) cusps C) papillary muscles D) arteries

D) arteries Feedback: Atrioventricular valves control blood flow between atria and ventricles.

Because of the distribution of the cardiac impulse by the conduction system, ventricular contraction begins

D) at the apex of the heart and pushes blood toward the semilunar valves Feedback: Contraction of the superior aspects of the ventricles would push blood toward the apex, making it harder for the ventricles to force the blood up and out through the semilunar valves.

While the atria of the heart are in systole the blood is being pumped where?

D) blood is being pumped into the ventricles. Feedback: Atrial systole and ventricular systole must alternate in order for blood to flow through the heart.

The alternate contraction and relaxation of the atria and ventricles are referred to as the

D) cardiac cycle Feedback: Correct Answer

The Frank-Starling law of the heart says that the higher the end diastolic volume, the

D) higher the stroke volume Feedback: The Frank-Starling law says that, within limits, the more the myocardial contractile cells are stretched prior to contraction, the stronger the resulting contraction will be.

What does not increase stroke volume?

D) increased arterial blood pressure Feedback: An increase in arterial blood pressure would make it harder for the ventricle to open the semilunar valves to eject blood. As a consequence, the end systolic volume would be higher, leading to a lower stroke volume.

The anterior and posterior interventricular sulci mark the position of which internal heart structure?

D) interventricular septum Feedback: A sulcus is a groove visible on the surface of an organ.

Damage to what parts of the brain would cause the body to have less control over cardiac activity?

D) medulla oblongata Feedback: The cardiac control centers are in the medulla oblongata.

The Purkinje fibers are found in which layer of the heart wall?

D) myocardium Feedback: The Purkinje fibers are modified cardiac muscle cells that carry impulses as part of the cardiac conducting system.

The cardiac pacemaker potential is caused by cyclic changes in membrane potential that occur in which of the following sequences? A) slow inflow of Na+ ; rapid K+ inflow; slow K+ outflow B) slow inflow of Ca2+ ; rapid Na+ inflow; rapid K+ outflow C) slow inflow of K+ without Na+ outflow; rapid Na+ inflow; rapid K+ outflow D) slow inflow of Na+ without K+ outflow; rapid Ca2+ inflow; rapid K+ outflow

D) slow inflow of Na+ without K+ outflow; rapid Ca2+ inflow; rapid K+ outflow

Damage to cells of the AV bundle would prevent the cardiac impulse from reaching the

D) ventricles Feedback: The AV bundle is located in the interventricular septum, and conducts impulses from the AV node to the ventricular myocardium.

Pressure in the ventricles would be highest during

D) ventricular systole Feedback: Pressure is highest when they are contracting and no blood is leaving.

The action potentials are slowed at the AV node to allow the: A. ventricles to repolarize. B. ventricles to completely empty of blood. C. pacemaker to reset for the next beat. D. atria to complete their contraction.

D. atria to complete their contraction

The tricuspid valve is closed: A. during rapid filling of the ventricles. B. when the mitral valve is open. C. while the atria are contracting. D. during ejection.

D. during ejection

D. frequently given to people with restricted coronary blood flow in order to reduce preload

Increased afterload will: A. increase stroke volume. B. decrease end-systolic volume. C. increase the duration of ventricular ejection. D. increase isovolumetric contraction.

D. increase isovolumetric contraction

Blood does not enter or leave the ventricles during the period called: A. ejection. B. rapid filling. C. atrial systole. D. isovolumetric contraction.

D. isovolumetric contraction

End-diastolic volume minus end-systolic volume is equal to: A. cardiac output. B. cardiac reserve. C. pulse volume. D. stroke volume.

D. stroke volume

Spontaneous opening of sodium (Na) channels marks the beginning of _____ of a myocardial cell

Depolarization

What even occurs during the QRS complex of an ECG?

Depolarization of the ventricles and re polarization of the atria

The relaxation phase of the cardiac cycle is referred to as:

Diastole

Match the condition with the description. A. allows blood to flow from the aorta to the pulmonary trunk B. a blood clot in a coronary vessel C. indicates low oxygen levels in peripheral blood vessels D. no rhythmic contractions of the myocardium E. heart rate less than 60 beats/minute bradycardia

E. heart rate less than 60 beats/minute

During what phase if the tricuspid valve closed?

Ejection phase

Which of the following is not important in preventing backflow of blood? a. chordae tendineae b. papillary muscles c. AV valves d. endocardium

Endocardium

The ________ layer secretes chemicals that help to regulate ionic environments and strength of contraction and serve as powerful vasoconstrictors. a. pericardial sac b. endocardium c. myocardium d. epicardium

Endocranium

Which of the following is mismatched? a. closing of calcium channels- plateau phase b. closure of sodium channels- early repolarization c. opening of sodium channels- depolarization d. opening of calcium channels- plateau phase e. opening of potassium channels- rapid repolarization

*not e

What is the Frank-Starling curve and what effects it?

1. Connecting the stroke volumes obtained at different preloads. 2. Changes in afterload will change the relationship between preload and stroke volume by shfting the curve up (decrease afterload).

True/False: Aortic Pressure and stroke volume are near control levels, thus afterload has not changed in the Patholigical condition.

1. FALSE. 2. In order to work against a faulty valve, ventricular pressure will have to increase. 3. So even though the aortic pressure and stroke volume is the same, the afterload increased and the ventricle has to compensate.

What is the association between the Heart Rate and the Cardiac Output?

1. Heart rate directly acts to increase cardiac output. 2. HR (beats/minute) X Stroke volume (SV, ml/beat) = CO (ml/min).

How does Venous Return affect the Preload?

1. If venous return is increased then a greater volume of blood will be in the ventricle at end diastole. 2. This will increase the radius and the pressure resulting in an increase in preload.

What does the increase in Preload result in?

1. Increase in the strength of contraction. 2. Increase in the velocity of shortening. 3. Increase in the extent of shortening. 4. Increase in stroke volume.

What are the factors involved in the shape of the passive filling curve?

1. It is dictated by the connective tissue supporting the myofilaments, in particular, by the content of collagen in the connective tissue. 2. In addition, non-contractile proteins with-in the cardiac muscle will resist stretch at longer muscle lengths.

What occurs to the heart when there is an increase in end diastolic volume (preload) and why does this occur?

1. It leads to the ability of the heart to generate greater pressures with increases in end diastolic volume is the result of optimizing sarcomere length. 2. It also increases the velocity of contraction. 3. Thus, an increase in preload will allow for an increase in the extent of shortening during the subsequent contraction. 4. In the heart, this will lead to an increase in amount of blood ejected from the heart (stroke volume).

What are the four determinants of Cardiac Function and what do they affect the most?

1. Preload - stroke volume. 2. Afterload - stroke volume. 3. Inotropic State - stroke volume. 4. Heart Rate - Cardiac output.

During the Cardiac cycle, what is considered the Preload?

1. Preload is the passive wall stress (or tension) at the end of diastole, just before you start to contract.

What is the Frank-Starling mechanisms (heterometric autoregulation) and how does it pertain to the heart?

1. The ability of the heart to regulate its output in proportion to its input. 2. It continually operates in the normal CVS to keep the stroke volumes of the right and left ventricles equal.

True/False: A change in preload will result in a change in afterload but a change in afterload will not result in a change in preload.

FALSE 1. If aortic pressure is abruptly increased during diastole, the ventricle will have to generate a greater pressure in order to eject blood into the aorta. 2. Ejecting blood against this higher pressure (increased afterload) will result in decreased stroke volume in the beat directly afterwards. 3. During the next period of diastole, the heart will begin to fill at a greater end systolic volume. 4. As venous return is not altered, volume in the heart at end diastole is increased resulting in an increased preload. 5. The increase in end-diastolic volume that results from the initial change in afterload will be pumped out and thereby allow stroke volume to once again match venous return.

Blood in the heart chambers provides most of the myocardium's oxygen and nutrient needs.

False

Step 8 systemic circuit

From the left ventricle, blood flows through the aortic valve to the aorta

step 2 (pulmonary circuit)

From the right atrium blood flows through the tricuspid valve to the right ventricle

Step 3 (pulmonary circuit)

From the right ventricle blood flow through the pulmonary valve into the pulmonary trunk

The earliest organ to form and begin function within the developing human is the ________. a. brain b. stomach c. lungs d. heart

Heart

Foramen

Hole

Increased body temperature tend to lead to a(n) _______ in heart rate.

Increase

The adrenal hormones, epinephrine and norepinephrine, _______ heart rate.

Increase

The baroreceptor reflex would cause the following event to occur if the reflex was caused by an increase in BP?

Increased parasympathetic stimulation of the heart

Withdrawal of parasympathetic stimulation (vagus nerve) _____ heart rate.

Increases

The cardiac cycle consists of a distinct relaxation and contraction phase. Which term is typically used to refer ventricular contraction while no blood is being ejected? a. systole b. diastole c. quiescent d. isovolumic contraction

Isovolumic contraction

In a healthy young adult, what happens to cardiac output when heart rate increases above 160 bpm? a. It increases. b. It decreases. c. It remains constant. d. There is no way to predict.

It decreases.

What happens to preload when there is venous constriction in the veins? a. It increases. b. It decreases. c. It remains constant. d. There is no way to predict.

It increases

What is the effect of norepinephrine on the heart?

It increases the rate and strength of contraction

What prevents the AV valves from swinging into the atria?

It pulls on the chordae tendinae

Why is it important for impulses from the atria to be delayed at the AV node before they pass into the ventricles?

It would go through the ventricles so quickly that they would begin contracting before the atria would finish contracting so the ventricles would not be as full

The myocardium would be the thickest in the ________. a. left atrium b. left ventricle c. right atrium d. right ventricle

Left Ventricle

An incompetent mitral valve may cause blood to back up into the:

Left atrium

Blood in the pulmonary veins returns to the:

Left atrium

An incompetent pulmonary semilunar valve could result in less blood reaching the ____

Lungs

The cardiovascular centers are located in which area of the brain? a. medulla oblongata b. pons c. mesencephalon (midbrain) d. cerebrum

Medulla oblongata

Of the three germ layers that give rise to all adult tissues and organs, which gives rise to the heart? a. ectoderm b. endoderm c. mesoderm d. placenta

Mesoderm

Which valve separates the left atrium from the left ventricle? a. mitral b. tricuspid c. pulmonary d. aortic

Mitral

What forms the bulk of the heart wall?

Myocardium

Which of the following layers of the heart and their functions are correctly matched?

Myocardium-cardiac muscle tissue that pumps blood out of the heart chambers

Which of these conditions results in a spontaneous depolarization in pacemaker cells? Select one: a. Voltage-gated Ca2+ ion channels close. b. All of these are correct. c. Na+ ions move into the cell through specialized Na+ ion channels. d. Membrane permeability to K+ ions increases.

Na+ ions move into the cell through specialized Na+ ion channels.

The P wave of an ECG indicates

atrial depolarization

The P wave of an ECG indicates Select one: a. ventricular repolarization. b. atrial depolarization. c. atrial repolarization. d. ventricular depolarization. e. threshold.

atrial depolarization

In which of the following ailments is characterized by asynchronous atrial muscle fiber contractions?

atrial fibrillation

List the phases of the cardiac cycle.

atrial systole, atrial diastole, ventricular systole, ventricular diastole

The sinus rhythm of a normal adult heart would be about a. 10 to 120 beats per minute. b. 70 - 80 beats per minute. c. 40 - 50 beats per minute. d. less than 40 beats per minute.

When a pacemaker potential in the SA node reaches threshold, a. permeability of the cell does not change. b. many voltage-gated Ca2+ channels open. c. RMP has been restored. d. voltage-gated Ca2+ channels close. e. the permeability to K+ ions increases.

Which of the following layers forms the bulk of the heart wall? a. pericardium b. myocardium c. visceral pericardium d. epicardium e. endocardium

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Chapter 20 Cardiovascular System

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