Ch 18 Cardiovascular System Practice Qs A&P 2

Match the following 1. pulmonary semilunar valve 2. tricuspid valve 3. aortic semilunar valve 4. mitral (bicuspid) valve a. valve between the right atrium and right ventricle b. valve between the left atrium and left ventricle c. prevents backflow of blood into the left ventricle d. prevents backflow of blood into the right ventricle

1. pulmonary semilunar valve D. prevents backflow of blood into the right ventricle 2. Tricuspid valve A. valve between the right atrium and right ventricle 3. Aortic semilunar valve C. prevents backflow of blood into the left ventricle 4. mitral (bicuspid) valve B. valve between the left atrium and left ventricle

Into which chamber of the heart do the pulmonary veins deliver blood? a. left atrium b. right ventricle c. left ventricle d. right atrium

A. left atrium - the pulmonary veins deliver oxygen-rich blood to the left atrium

The normal pacemaker of the heart is the ________. A. AV bundle b. AV node C. bundle branches d. SA node e. subendocardial conducting network (Purkinje fibers)

D. SA node - The SA node generates impulses faster than the other node and sets the pace for the heart

Choose the correct sequence of electrical current flow through the heart wall. a. subendocardial conducting network, AV node, AV bundle, right and left bundle branches, SA node b. AV node, subendocardial conducting network, AV node, AV bundle, right and left bundle branches c. SA node, subendocardial conducting network, AV node, AV bundle, right and left bundle branches d. AV node, SA node, subendocardial conducting network, AV bundle, right and left bundle branches e. SA node, AV node, AV bundle, right and left bundle branches, subendocardial conducting network

E. SA node, AV node, AV bundle, right and left bundle branches, subendocardial conducting network - Impulses generated by the SA node spread to the AV node, then to the AV node, then to the AV bundle, then to the bundle branches, and finally to the subendocardial conducting network (Purkinje fibers)

The interventricular septum forms a dividing wall between the __________. a. left and right atria b. right atrium and right ventricle c. right ventricle and left atrium d. left atrium and left ventricle e. left and right ventricles

E. left and right ventricles - the interventricular septum separates the two ventricles

The absolute refractory period refers to the time during which _______. a.the muscle cell will respond only to a sub-threshold stimulus b. the muscle cell will respond only to an exceptionally strong stimulus c. the muscle cell is ready to respond to any stimulus d. the muscle cell is ready to respond to a threshold stimulus e. the muscle cell will not respond to a stimulus of any strength

E. the muscle cell will not respond to a stimulus of any strength - During the absolute refractory period, a muscle cell will not respond to a stimulus of any strength

Match the following 1. posterior interventricular artery 2. anterior interventricular artery 3. right marginal artery 4. circumflex artery a. supplies blood to the lateral right side of the myocardium b. runs to the apex of the heart c. supplies blood to the interventricular septum and anterior walls of both ventricles d. supplies blood to the left atrium and posterior walls of the left ventricles

1. posterior interventricular artery b. runs to the apex of the heart 2. anterior interventricular artery C. supplies blood to the interventricular septum and anterior walls of both ventricles 3. right marginal artery A. supplies blood to the lateral right side of the myocardium 4. circumflex artery D. supplies blood to the left atrium and posterior walls of the left ventricle

Match the following 1. stroke volume 2. cardiac cycle 3. diastole 4. cardiac output 5. systole a. the events associated with blood flow through the heart during one complete heartbeat b. contraction c. relaxation d. the volume of blood pumped by one ventricle with each heartbeat e. the amount of blood pumped by each ventricle in one minute

1. stroke volume D. the volume of blood pumped by one ventricle with each heartbeat 2. cardiac cycle A. the events associated with blood flow through the heart during one complete heartbeat 3. diastole C. relaxation 4. cardiac output E. the amount of blood pumped by each ventricle in one minute 5. systole B. contraction

The P-wave of an electrocardiogram represents _______. a. atrial depolarization b. atrial repolarization c. ventricular repolarization d. ventricular depolarzation

A. atrial depolarization - The P wave reflects the depolarization of the atria. The QRS complex shows ventricular depolarization, and the T wave is generated by ventricular repolarization. Since the QRS complex is so large, it obscures the wave that is generated by atrial repolarization

The second heart sound (the "dup" of "lub-dup") is caused by the ________. a. closure of the semilunar valve b. closure of the atrioventricular valves c. opening of the atrioventricular valves d. opening of the semilunar valve

A. closure of the semilunar valves - The first heart sound (the the "lup" of "lub-dup") is generated by the closure of the atrioventricular valves. The second heart sound (the "dup" sound) is caused by closure of the semilunar valves.

Which is the correct sequences of layers in the heart wall, starting with outer layer? a. epicardium, myocardium, endocardium b. myocardium, pericardium, endocardium c. endocardium, epicardium, myocardium d. parietal pericardium, myocardium, endocardium e. endocardium, smooth muscle, epicardium

A. epicardium, myocardium, endocardium - The superficial epicardium, the middle myocardium, and the inner endocardium form the heart wall

The endocardium is composed of _________. a. cardiac muscle cells b. squamous epithelium c. elastic cartilage d. cuboidal epithelium e. columnar epithelium

B. Squamous epithelium - The endocardium is a thin sheet of simple squamous epithelium (endothelium)

The ________ are attached to the AV valve flaps. a. pectinate muscles b. chordae tendineae c. trabeculae carneae d. papillary muscles

B. chordae tendineae - The chordae tendineae, also known as the heartstrings, are attached to the flaps of the AV valves and prevent the valves from blowing into the atria when the ventricles contract

The coronary arteries arise from the _________. a. pulmonary trunk b. right atrium c. aorta d. inferior vena cava e. superior vena cava

C. aorta - the two coronary arteries that supply the heart arise from the base of the aorta

The superior chambers of the heart are called the _______. a. ventricles b. coronary chambers c. atria d. cavae

C. atria - The heart has four chambers: right atrium, right ventricle, left atrium, and left ventricle. The atria are the superior chambers; the ventricles are inferior to the atria

The lining of the heart chambers is called the ______. a. epicardium b. pericardium c. endocardium d. myocardium

C. endocardium - the layers of the heart wall from superficial to deep are the epicardium, the myocardium, and the endocardium. The endocardium lines the heart chambers

During systemic circulation, blood leaves the __________. a. lungs and flows directly to the left atrium b. right ventricle and flows directly to the aorta c. left ventricle and flows directly to the aorta d. right atrium and flows directly to the lungs e. right ventricle and flows directly to the lungs

C. left ventricle and flows directly to the aorta - The movement of oxygenated blood from the left ventricle to the aorta constitutes part of the systemic circuit

When the mitral valve closes, it prevents the backflow of blood from the __________. a. left atrium into the left ventricle b. left ventricle into the aorta c. left ventricle into the left atrium d. right atrium into the right ventricle e. right ventricle into the pulmonary trunk

C. left ventricle into the left atrium - The mitral valve closes to prevent the backflow of blood from the left ventricle into the left atrium

The _________ nerve carries parasympathetic fibers to the sinoatrial (SA) node. a. facial b. accessory c. hypoglossal d. vagus

D. vagus - the vagus nerve carries parasympathetic fibers to the SA node

The trabeculae carneae are located in the ________. a. atria b. epicardium c. endocardium d. ventricles

D. ventricles - the trabeculae carneae are located in the ventricles

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? a. cardiac tamponade b. incompetent cardiac valve c. angina pectoris d. myocardial infarction

b. incomplete cardiac valve - an incomplete cardiac valve produces a swishing sound on auscultation

Which of the following would lead to a decrease in HR? a. sharply decreased blood volume b. norepinephrine c. parasympathetic stimulation d. exercise

c. parasympathetic stimulation - Sympathetic stimulation (for example, exercise) can lead to the release of epinephrine and norepinephrine, which increase heart rate. A sharp decrease in blood volume also leads to an increase in heart rate. Low metabolic rate, cold temperatures, and parasympathetic stimulation decrease heart rate.

Freshly oxygenated blood is delivered to the _____, and then it passes into the _____ to be pumped to the body tissues (systemic circuit) a. left atrium; left ventricle b right ventricle; right atrium c. right atrium; right ventricle d. left ventricle; left atrium

A. left atrium; left ventricle - The left side of the heart pumps blood to the body tissues and is known as the systemic circuit pump. Freshly oxygenated blood from the lungs is returned to the left atrium. From the left atrium, the blood flows into the left ventricle. The left ventricle then pumps the blood to the aorta, which distributes it to the body tissues (systemic circuit).

The structure just deep to the fibrous pericardium is the _________. a. parietal layer of the serous pericardium b. visceral layer of the serous pericardium c. diaphragm d. endocardium e. epicardium f. myocardium

A. parietal layer of the serous pericardium - the pericardial sac is lined by a serous membrane called the parietal pericardium

The inferior vena cava brings blood from the lower regions of the body and empties into the _________. a. right atrium b. aorta c. left ventricle d. left atrium e. right ventricle

A. right atrium - The right atrium receives blood both from the superior and inferior venae cavae

During pulmonary circulation, blood leaves the _______. a. right ventricle and flows directly to the lungs b. right ventricle and flows directly to the aorta c. left ventricle and flows directly the lungs d. right atrium and flows directly to the lungs e. right atrium and flows directly to the left ventricle

A. right ventricle and flows directly to the lungs - the movement of oxygen-poor blood from the right ventricle to the lungs is part of the pulmonary circuit

Cardiac output is ______. a. the amount of blood pumped out of each ventricle in one minute b. the number of impulses fired by the SA node in one minute c. the amount of blood pumped out of the heart during every ventricular contraction d. the number of times the heart beats in one minute e. the amount of blood filling each ventricle at the end of diastole

A. the amount of blood pumped out of each ventricle in one minute - cardiac output= heart rate x stroke volume

What part of the heart is considered the systemic circuit pump? a. the left ventricle b. the right atrium c. the right ventricle d. the pericardium

A. the left ventricle - The left ventricle pumps blood to most body tissues and is considered the systemic circuit pump.

In the fetus, blood from the left and right sides of the heart normally mix. a. True B. false

A. true - In utero, blood from the right atrium is shunted to the left atrium via the foramen ovale. Additionally, the ductus arteriosus shunts blood from the pulmonary trunk to the aorta, bypassing the pulmonary circuit.

Which of the following is NOT a role of the fibrous pericardium? a. It anchors the heart to surrounding structures b. it facilitates heart contraction c. It prevents the heart from overfilling with blood d. it protects the heart

B. It facilitates heart contraction - The fibrous pericardium is the superficial part of the pericardium that encloses the heart. It protects the heart, prevents the heart from overfilling with blood, and anchors the heart to surrounding structures.

The vessels that carry oxygen to the myocardium are called ________. a. aortic arteries b. coronary arteries c. coronary veins d. pulmonary veins e. pulmonary arteries

B. coronary arteries - The arterial supply of the coronary circulation is provided by the right and left coronary arteries

The contractile cardiac muscle fibers of the myocardium behave as a single, coordinated unit called a _______. a. cardiac cycle b. functional syncytium c. contractile unit d. sarcomere e. pacemaker

B. functional syncytium - Because cardiac cells are electrically coupled by gap junctions, they behave as a single unit called a functional syncytium

The most muscular chamber of the heart is the _______. a. right ventricle b. left ventricle c. right atrium d. left atrium

B. left ventricle - The left side of the heart is the systemic circuit pump. Since the left ventricle pumps blood to the entire body, it makes sense that it is a more powerful pump than the right ventricle, which only needs to pump blood to the nearby lungs. The powerful pumping ability of the left ventricle is due in part to its thick musculature; the walls of the left ventricle are about three times thicker than the walls of the right ventricle. Since the demands on the left ventricle are so great, it receives the highest percentage of the coronary blood supply

Guided by powerful signaling molecules, the human heart develops from ______. a. ectoderm b. mesoderm c. endoderm d. cardioderm

B. mesoderm - The human heart, derived from mesoderm, forms a single chamber, or heart tube, that is pumping blood by the 23rd day of gestation

The tricuspid valve is located between the _______. a. right and left atria b. right atrium and right ventricle c. right ventricle and the aorta d. right and left ventricles e. left atrium and left ventricles

B. right atrium and right ventricle - The tricuspid valve is located between the right atrium and the right ventricle

The role of the atrioventricular node (AV) is to ______. a. conduct impulses to the sinoatrial node (SA node) b. slow down impulses so that the atria can contract to fill the adjacent ventricles with blood c. initiate a sinus rhythm d. initiate ventricular depolarization

B. slow down impulses so that the atria can contract to fill the adjacent ventricles with blood - An impulse of the heart originates at the sinoatrial (SA) node. The impulse is then transmitted to the atrioventricular (AV) node, where the impulse slows down to allow the atria to completely contract, thereby filling the adjacent ventricles. The AV node then transmits the impulse to the atrioventricular bundle (bundle of His), which branches into left and right bundle branches. The bundle branches give rise to the subendocardial conducting network (Purkinje fibers), which transmit the impulse to the ventricle walls and stimulate ventricular contraction.

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? a. the parietal layer of serous pericardium b. the epicardium c. the fibrous pericardium d. the pericardial sac

B. the epicardium - The epicardium lies outside the surface of the heart and is an integral part of the cardiac wall.

The noncontractile cardiac muscle cells that initiate their own depolarization and cause depolarization of the rest of the heart are called _______. a. cardioinhibitory centers b. gap junctions c. pacemaker cells d. desmosomes e. intercalated discs

C. Pacemaker cells - Pacemakers are non-contractile cardiac muscle cells with an unstable resting membrane potential

Which of the following is a difference between cardiac muscle and skeletal muscle? a. unlike skeletal muscle, cardiac muscle is not striated b. Unlike skeletal muscle, cardiac muscle does not use a sliding filament mechanism for contraction c. Unlike skeletal muscle cells, cardiac muscle cells can be autorhythmic d. unlike skeletal muscle cells, cardiac muscle cells do not rely on calcium ions for contraction

C. Unlike skeletal muscle cells, cardiac muscle cells can be autorhythmic - Cardiac muscle is striated and utilizes the sliding-filament mechanism for contraction, like skeletal muscle. Both cardiac and skeletal muscle depend upon calcium ions for contraction. Unlike skeletal muscle, cardiac muscle cells have a greater concentration of mitochondria, giving cardiac cells a high resistance to fatigue. Cardiac muscle cells are highly dependent upon oxygen in order to carry out aerobic respiration. Cardiac muscle cells die faster than skeletal muscle cells if deprived of oxygen. Additionally, the plasma membranes of cardiac muscle cells interlock, while skeletal muscle cell fibers are independent. Cardiac cells can be autorhythmic, a property not seen in skeletal muscle fibers.

An enlarged R wave on an ECG would indicate _________. a. repolarization abnormalities b. a myocardial infarction c. an enlarged ventricle d. cardiac ischemia

C. an enlarged ventricle - an enlarged ventricle would appear as an enlarged R wave on an ECG

From the perspective of blood returning from the systemic circuit, identify the correct sequence of blood through the chambers of the heart. a. lungs, right ventricle, left ventricle, right atrium, left atrium b. left ventricle, left atrium, lungs, right ventricle, right atrium c. right atrium, right ventricle, lungs, left atrium, left ventricle d. right ventricle, left ventricle, left atrium, lungs, right atrium e. left atrium, left ventricle, right ventricle, right atrium, lungs

C. right atrium, right ventricle, lungs, left atrium, left ventricle - As oxygen-poor blood returns to the heart from the systemic circuit, it will pass through the right atrium, right ventricle, lungs, left atrium, and left ventricle

The cardiac cycle includes all of the following events EXCEPT _______. a. the movement of impulse from the SA node to all regions of the heart wall b. the changes in pressure gradients in all chambers of the heart c. the number of times the heart beats in one minute d. the changes in blood volume in all chambers of the heart e. the closing and opening of the heart valves during each heartbeat

C. the number of times the heart beats in one minute - the cardiac cycle refers to the mechanical events occurring during one heartbeat

Which of the following statements is NOT true about the shape, position, and location of the heart? a. Approximately two-thirds of the heart is found to the left of the midline. b. The heart is located between the two lungs within the mediastinum. c. The heart is shaped like a cone with the base facing the right shoulder. d. The heart is enclosed in a double-layered sac called the pleural membrane.

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

Which of the following are correctly paired? a. heart block: uncoordinated atrial and ventricular contraction b. fibrillation: premature contraction c. arrhythmia: atrioventricular (AV) node failure d. ectopic focus: an abnormal pacemaker

D. ectopic focus: an abnormal pacemaker - Extrasystole, or premature contraction, can be caused by ectopic or abnormal pacemakers (also called ectopic foci). An ectopic focus can result when the sinoatrial (SA) node is defective. Additionally, some substances (such as caffeine and nicotine) consumed in excess can generate an ectopic focus. Any defect in the intrinsic conduction system of the heart can generate an irregular heart rhythm (an arrhythmia). Damage to the atrioventricular (AV) node can lead to a heart block. In a complete heart block, impulses do not reach the ventricles; as a result, the ventricles beat at their intrinsic rate, which is too slow to maintain adequate circulation. Fibrillation is characterized by rapid and irregular or out-of-phase contractions of the heart chambers.

Which of the following factors gives the myocardium its high resistance to fatigue? a. gap junctions b. the coronary circulation c. the presence of intercalated discs d. a very large number of mitochondria in the cytoplasm

d. a very large number of mitochondria in the cytoplasm - Twenty-five to thirty-five percent of the volume of a myocardial cell is composed of large mitochondria, which provide these cells with a great resistance to fatigue.