Heart A&P
When the left ventricle contracts, the diameter of the ventricular chamber
decreases
When the left ventricle contracts, the distance from the apex to the base
decreases
If the connection between the SA node and AV node becomes blocked,
the ventricles will beat more slowly.
The P wave of the electrocardiogram is closely followed by __________.
contraction of both atria
As blood leaves the right ventricle it passes through the ________ and then into the pulmonary trunk.
conus arteriosus
The first blood vessels to branch from the aorta are the ________ arteries.
coronary
The heart beats approximately ________ times each day.
100,000
The Heart Use the figure to answer the following question: Which chamber receives oxygenated blood from the pulmonary circuit?
16
There are ________ pulmonary veins.
4
The following is a list of vessels and structures that are associated with the heart. 1. right atrium 2. left atrium 3. right ventricle 4. left ventricle 5. venae cavae 6. aorta 7. pulmonary trunk 8. pulmonary veins What is the correct order for the flow of blood entering from the systemic circulation?
5, 1, 3, 7, 8, 2, 4, 6
The heart pumps approximately ________ liters of blood each day.
8,000
Pacemaker cells isolated from the SA node generate action potentials at ________ beats per minute.
80 - 100
Which of these is an important difference between cardiac muscle and skeletal muscle?
Cardiac muscle can't be tetanized.
What is the function of the structures indicated by the red arrow?
Permit strong connections between adjacent cells Transfer force of contraction from cell to cell Propagate action potentials from cell to cell All of the listed responses are correct
The duration of the ventricular action potential is approximately equal to the __________ interval in the electrocardiogram.
Q-T interval
Abnormally slow depolarization of the ventricles would most change the shape of the ________ in an ECG tracing.
QRS complex
The rapid depolarization phase in the ventricular action potential appears in the electrocardiogram as the __________.
QRS complex
Depolarization of the ventricles is represented on an electrocardiogram by the
QRS complex.
Which wave is the largest in the electrocardiogram?
R
Into which chamber of the heart will blood flow next after the vessel indicated by the red arrow?
Right atrium
The conducting system in the heart begins in the __________.
SA node
The plateau phase of the ventricular action potential corresponds to the __________ phase of the electrocardiogram.
ST segment
The arrow indicates the pericardial cavity. What term best describes the membrane on both sides of the cavity?
Serous pericardium
If there is a complete block between the SA node and the AV node, how would the ECG be affected?
The rate of P waves will be faster than the rate of QRS complexes.
Which of the labeled valves will open during ventricular systole to allow the flow of blood to the lungs?
The semilunar valve labeled B
The adult heart is roughly the size of
a man's clenched fist.
In cardiac muscle
about 20 percent of the calcium ion required for contraction comes from outside the cell.
The left ventricle pumps blood to the
aorta
The __________ valve prevents backward flow of blood into the left ventricle.
aortic
Which of the following descriptions matches the term near the left fifth intercostal space?
apex of heart
The earlike extension of the atrium is the
auricle
The bicuspid or mitral valve is located
between the left atrium and left ventricle.
The ________ valve prevents backward flow into the left atrium.
bicuspid
Rupture of the papillary muscles in the left ventricle may result in
bicuspid prolapse. mitral regurgitation. mitral valve prolapse. bicuspid regurgitation. All of the answers are correct
During the T wave of the electrocardiogram, the ventricles are
both repolarizing and relaxing.
Heart rate is controlled by __________.
both the right vagus and sympathetic nerves
During the plateau phase of the cardiac action potential, which ion is entering the cardiac muscle cell?
calcium
The long plateau phase of the cardiac muscle action potential is due to
calcium channels remaining open.
Pacemaker cells in the SA node
can spontaneously depolarize.
Most of the middle layer in the heart wall is composed of
cardiac muscle cells.
The term used to describe fluid collecting in the pericardial cavity that restricts the movement of the heart is known as
cardiac tamponade.
The cusps (leaflets) of atrioventricular valves attach directly to
chordae tendineae.
The function of an atrium is to
collect blood then pump it to the ventricle.
The interventricular sulci and coronary sulcus
contain veins. are grooves on the surface of the heart. contain arteries. contain fat. All of the answers are correct
The ________ deliver(s) blood to the myocardium.
coronary arteries
The great and middle cardiac veins drain blood into the
coronary sinus.
When a blood clot forms on a ruptured plaque in a coronary artery, the condition is referred to as a(n)
coronary thrombosis.
The Heart Use the figure to answer the following question: Identify the structure labeled "6
cusp of tricuspid valve
The P wave of the electrocardiogram is a signal from
depolarization of the atria.
The auricle is the __________.
ear-like extension of the atrium
Artery is to ________ as vein is to ________.
efferent; afferent
The visceral pericardium is the same as the
epicardium
The structure that permits blood flow from the right atrium to the left atrium in the fetal circulation is the
foramen ovale.
The pulmonary veins carry blood to the
heart
If the pacemaker cells in the SA node become more permeable to potassium ions, the
heart rate will decrease and cells will hyperpolarize.
The atrioventricular valves permit blood flow
in one direction only.
The foramen ovale in the fetal heart is located in the
interatrial septum.
Intercalated discs serve to transfer ________ from cell to cell.
ionic currents action potentials electrical signals the force of contraction All of the answers are correct
Blood returning to the heart from the pulmonary circuit first enters the __________.
left atrium
Blood returning to the heart from the pulmonary circuit first enters the
left atrium.
Blood is supplied to the left atrium by the
left coronary artery.
The circumflex branch and the anterior interventricular artery are branches of the
left coronary artery.
The Heart Use the figure to answer the following question: Identify the structure labeled "21
ligamentum arteriosum
Which of these organs is not found in the mediastinum?
lung
The coronary sulcus is a groove that
marks the border between the atria and ventricles.
In the middle of the thoracic cavity is a region occupied by the heart, great vessels, thymus, esophagus, and trachea called the
mediastinum.
When the semilunar valves close, the AV valves then
open
In order to perform a CABG, a cardiac surgeon must
open the pericardial sac.
The pulmonary veins carry __________ blood to the __________ atrium.
oxygenated; left
The right pulmonary veins carry ________ blood to the ________ .
oxygenated; left atrium
The Heart Use the figure to answer the following question: Identify the structure labeled "8.
papillary muscles
Excess fluid in the ________ causes cardiac tamponade.
pericardial cavity
The papillary muscles function to __________.
prevent the AV valves from reversing into the atria
Contractions of the papillary muscles
prevent the atrioventricular valves from reversing into the atria.
The connective tissue fibers of the myocardium
provide elasticity to help return the heart to its normal size. help distribute the forces of contraction. provide physical support for cardiac muscle. add strength and prevent overexpansion of the heart. All of the answers are correct
The Heart Use the figure to answer the following question: Identify the structure labeled "19
pulmonary semilunar valve
Blood leaves the right ventricle by passing through the
pulmonary valve.
Compared to the right ventricle, the left ventricle has all the following characteristics, except that it
pumps a greater volume.
Cardiac cells damaged by infarction will show which of the following?
release of CK-MB into the circulation release of troponin T and I into the circulation switch to anaerobic metabolism release of enzymes into the circulation All of the answers are correct
The right ventricle pumps blood to the
right and left lungs.
Blood flowing in the vena cava will next enter the __________.
right atrium
Cardiac veins empty their blood into the __________.
right atrium
Blood returning to the heart from the systemic circuit first enters the
right atrium.
Coronary veins empty into the
right atrium.
The marginal branch and posterior interventricular branch are branches of the
right coronary artery.
Which of the following are involved in the pulmonary circuit?
right ventricle, pulmonary trunk, left atrium
The pulmonary semilunar valve prevents backward flow into the
right ventricle.
Analysis of the electrocardiogram can reveal all of the following, except the
stroke volume.
The right atrium receives blood from the
systemic circuit.
As a result of the long refractory period in the cardiac action potential, cardiac muscle cannot exhibit
tetany.
Blood is supplied to the myocardium by
the coronary arteries.
Tetanic muscle contractions don't occur in a normal cardiac muscle because
the refractory period lasts until the muscle relaxes.
The normal pacemaker of the heart is located in
the sinoatrial node.
Blood flowing into the heart from the venae cavae flows next through the ________ valve.
tricuspid
The T wave on an ECG tracing represents
ventricular repolarization.
The epicardium is also known as the __________.
visceral pericardium
The following are structural components of the conducting system of the heart. 1. Purkinje fibers 2. AV bundle 3. AV node 4. SA node 5. bundle branches The sequence in which excitation would move through this system is
4, 3, 2, 5, 1.
Cardiac muscle cells and skeletal muscle cells differ in a few ways. Which of the following is not one of them?
Cardiac muscle cells lack transverse tubules.
In cardiac muscle, the fast depolarization phase of the action potential is the result of
increased membrane permeability to sodium ions.
The pulmonary arteries carry blood to the
lungs
