Chapter 18: The cardiovascular System: the heart (book)

mesoderm

Guided by powerful signaling molecules, the human heart develops from __________.

the number of times the heart beats in one minute

The cardiac cycle includes all of the following events EXCEPT __________.

functional syncytium

The contractile cardiac muscle fibers of the myocardium behave as a single, coordinated unit called a __________.

aorta

The coronary arteries arise from the __________.

squamous epithelium

The endocardium is composed of __________.

right atrium

The inferior vena cava brings blood from the lower regions of the body and empties into the __________.

the left ventricle

What part of the heart is considered the systemic circuit pump?

left ventricle into the left atrium

When the mitral valve closes, it prevents the backflow of blood from the __________.

epicardium, myocardium, endocardium

Which is the correct sequence of layers in the heart wall, starting with the outer layer?

cardiac output

the amount of blood pumped by each ventricle in one minute

Cardiac cycle

the events associated with blood flow through the heart during one complete heartbeat

mitral (bicuspid) valve

valve between the left atrium and left ventricle

tricuspid valve

valve between the right atrium and right ventricle

incompetent cardiac valve

A doctor puts his stethoscope on a patient's chest over the location of the heart and hears an abnormal swishing sound. Which of the following conditions is the best diagnosis for the patient's condition?

an enlarged ventricle

An enlarged R wave on an ECG would indicate __________.

the amount of blood pumped out of each ventricle in one minute (cardiac output = heart rate × stroke volume)

Cardiac output is __________.

left ventricle and flows directly to the aorta

During pulmonary circulation, blood leaves the __________.

left atrium; left ventricle

Freshly oxygenated blood is delivered to the __________, and then it passes into the __________ to be pumped to the body tissues (systemic circuit).

right atrium, right ventricle, lungs, left atrium, left ventricle

From the perspective of blood returning from the systemic circuit, identify the correct sequence of blood flow through the chambers of the heart.

True

In the fetus, blood from the left and right sides of the heart normally mix. (true or false)

left atrium

Into which chamber of the heart do the pulmonary veins deliver blood?

atrial depolarization

The P wave of an electrocardiogram represents __________.

chordae tendineae

The __________ are attached to the AV valve flaps.

Vagus

The __________ nerve carries parasympathetic fibers to the sinoatrial (SA) node.

the muscle cell will not respond to a stimulus of any strength

The absolute refractory period refers to the time during which __________.

endocardium

The lining of the heart chambers is called the __________.

left ventricle

The most muscular chamber of the heart is the __________.

pacemaker cells

The noncontractile cardiac muscle cells that initiate their own depolarization and cause depolarization of the rest of the heart are called __________.

SA node

The normal pacemaker of the heart is the __________.

Slow down impulses so that the atria can contract to fill the adjacent ventricles with blood

The role of the atrioventricular node (AV node) is to __________.

closure of the semilunar valves

The second heart sound (the "dup" of "lub-dup") is caused by the __________.

parietal layer of the serous pericardium

The structure just deep to the fibrous pericardium is the __________.

atria

The superior chambers of the heart are called the __________.

systole

contraction

aortic semilunar valve

prevents backflow of blood into the left ventricle

diastole

relaxation

anterior interventricular artery

supplies blood to the interventricular septum and anterior walls of both ventricles

right marginal artery

supplies blood to the lateral right side of the myocardium

circumflex artery

supplies blood to the left atrium and posterior walls of the left ventricle

stroke volume

the volume of blood pumped by one ventricle with each heartbeat

a very large number of mitochondria in the cytoplasm

Which of the following factors gives the myocardium its high resistance to fatigue?

Unlike skeletal muscle cells, cardiac muscle cells can be autorhythmic.

Which of the following is a difference between cardiac muscle and skeletal muscle?

left and right ventricles

The interventricular septum forms a dividing wall between the __________.

ventricles

The trabeculae carneae are located in the __________.

right atrium and right ventricle

The tricuspid valve is located between the __________.

coronary arteries

The vessels that carry oxygen to the myocardium are called __________.

The heart is enclosed in a double-layered sac called the pleural membrane.

Which of the following statements is NOT true about the shape, position, and location of the heart?

the epicardium

Which of the following structures is superficial to the heart wall and serves to protect the heart, anchor the heart, and prevent the heart from overfilling?

the mitral, or bicuspid, valve

Which of the following valves is most often faulty in the heart?

parasympathetic stimulation

Which of the following would lead to a decrease in heart rate?

pulmonary semilunar valve

prevents backflow of blood into the right ventricle

posterior interventricular artery

runs to the apex of the heart