Chapter 20 Heart

Which of the following is called the cardiac pacemaker?

sinoatrial node

Which of the following is measured in milliliters per beat?

stroke volume

What is the term for contraction of a heart chamber?

systole

Someone suffering a heart attack in his anterior lower right ventricle probably had a blockage in which coronary artery? A) anterior interventricular artery B) circumflex artery C) posterior interventricular artery D) marginal artery

A) anterior interventricular artery

A deep wound to the upper thigh might damage the _____________ artery. A) femoral B) popliteal C) anterior tibial D) peroneal

A) femoral

A unique venous system, called the ________________, carries blood directly from the intestines to the liver for processing rather than directly into the inferior vena cava. A) hepatic portal system B) superior mesenteric vein C) saphenous vein D) gonadal vein

A) hepatic portal system

The aortic semilunar valve prevents blood from returning to the _____. A) left ventricle B) aorta C) right ventricle D) left atrium

A) left ventricle

Which of the following statements about autonomic tone is FALSE?

A. Resting heart rate will be 70-80 beats per minute. B. Sympathetic effects dominate in a resting healthy adult. C. Parasympathetic rates dominate in a resting healthy adult. D. ACh and NE are released at the nodes.

The layer of the heart that forms a smooth, protective lining of the heart chambers and valves is the _______________. A) endocardium B) myocardium C) epicardium D) parietal pericardium

A. endocardium

The bicuspid valve __________________. A) is located on the left side of the heart B) guards the auricles of the heart C) guards the entrance to the aorta D) guards the entrance to the pulmonary trunk

A. is located on the left side of the heart

A condition in which there is a congenital predisposition for a ruptured aorta is _____________. A) a metabolic disorder of fatty acid metabolism B) Marfan syndrome C) Niemann-Pick type C disease D) coronary artery disease

B) Marfan syndrome

What does the electrocardiogram (ECG) QRS wave indicate is happening in the heart? A) The atria are depolarizing. B) The ventricles are depolarizing while the atria repolarize. C) The ventricles are repolarizing. D) The heart is at rest

B) The ventricles are depolarizing while the atria repolarize.

How does the impulse to contract slow down slightly before it is transferred into the ventricles? A) It makes a detour and travels to the brain and back. B) There is a parasympathetic brake on the AV node. C) Junctional fibers leading into the AV node have very small diameters. D) The skeleton of the heart prevents the impulse from being transmitted rapidly.

B) There is a parasympathetic brake on the AV node.

Blood is drained from the face, scalp, and superficial regions of the neck by the _______________. A) carotid arteries B) external jugular veins C) internal jugular veins D) brachiocephalic veins

B) external jugular veins

Freshly oxygenated blood enters the heart through the ______________, and is pumped out the _____________. A) right atrium; aorta B) left atrium; aorta C) right ventricle; pulmonary arteries D) left ventricle; pulmonary arteries

B) left atrium; aorta

The pulmonary semilunar valve prevents a back-flow of blood into the _____. A) pulmonary artery B) right ventricle C) left ventricle D) right atrium

B) right ventricle

The inability of the left ventricle to pump blood adequately to the body's cells is indicative of ________________. A) an embolus B) cardiac tamponade C) congestive heart failure D) asystole

C) congestive heart failure

When do the A-V valves close during the cardiac cycle? A) when pressure inside the ventricles is at its lowest B) when pressure inside the atria is greater than that inside the ventricles C) when ventricular pressure exceeds that of the atria D) when pressure is greater in the aorta than in the left ventricle

C) when ventricular pressure exceeds that of the atria

How many openings are there in the right atrium? A) 1 B) 2 C) 3 D) 4

D) 4

Which artery supplies blood to the ilium and muscles of the lower back? A) aorta B) common iliac artery C) internal iliac artery D) iliolumbar artery

D) iliolumbar artery

The _____________ has the thickest wall because it pumps blood to the ________________. A) right atrium; systemic circuit B) right ventricle; lungs C) left atrium; lungs D) left ventricle; systemic circuit

D) left ventricle; systemic circuit

The _____ valve lies between the right atrium and right ventricle. A) bicuspid B) aortic semilunar C) pulmonary semilunar D) tricuspid

D) tricuspid

Which membrane is closest to the heart muscle? A) pericardial sac B) fibrous pericardium C) parietal pericardium D) visceral pericardium

D) visceral pericardium

What effect does epinephrine have on the SA node?

It increases heart rate.

What structures in the conduction system conduct impulses very rapidly to the ventricular myocardium?

Purkinje fibers

Which of the following occurs during the first phase of ventricular systole?

The AV valves close, and ventricular pressure rises.

The left ventricle pumps blood into the __________.

ascending aorta

The right and left coronary arteries originate at the base of the __________.

ascending aorta

The plateau in the action potential is caused by the entry of __________ ions.

calcium

Which vessels have very thin walls and are often called exchange vessels because they allow for the exchange of nutrients, gases, and wastes with surrounding tissues?

capillaries

What produces the "lubb" of the first heart sound?

closing of the atrioventricular valves

A large vein that opens into the right atrium and brings in venous blood from the heart tissue is the __________.

coronary sinus

Which layer of the heart wall is the visceral pericardium?

epicardium

Which of the following could increase the strength of the contraction of a ventricle?

increased stretch on the ventricle

Which network of blood vessels carries blood to and from the gas exchange surfaces in the lungs?

pulmonary circuit

Which chamber of the heart receives blood from the superior and inferior venae cavae?

right atrium

Which of the following contains the trabeculae carneae?

right ventricle

Which valve is found between the right atrium and the right ventricle?

tricuspid

The QRS complex on the ECG represents __________.

ventricular depolarization

Which layer of the following serves the dual purpose of forming the inner layer of the pericardium and forming the outermost wall of the heart? A) fibrous pericardium B) parietal pericardium C) visceral pericardium D) myocardium

visceral pericardium