Chapter 18 Poll Questions

Of the following layers of the heart wall, which consumes the most energy?

• endocardium

• visceral pericardium

• epicardium

• myocardium

• none of the above

Which of the following structures is an exception to the general principle surrounding blood vessel oxygenation levels?

• pulmonary veins

• aorta

• pulmonary artery

• both a and c

The right atrium receives blood from the ______ circuit, while the left atrium receives blood from the _____ circuit. In addition, the ______ pumps blood to the pulmonary circuit, while the ______ pumps blood to systemic circuit.

• pulmonary; systemic; left; ventricle, right ventricle

• systemic; pulmonary; right ventricle; left ventricle

• pulmonary; pulmonary; left ventricle, left ventricle

• systemic; systemic; right ventricle, right ventricle

• none of the above

Which layer of the heart contains the contractile muscle fibers?

• fibrous pericardium

• endocardium

• myocardium

• epicardium

• both a) and d)

The coronary arteries lie within the atrioventricular groove. The groove divides ______ and ______.

• atria; ventricles

• left atrium; right atrium

• right ventricle; left ventricle

• tricuspid valve; bicuspid valve

• none of the above

The heart valves allow blood to flow through the heart in one direction: True or False. The valves open or close in response to pressure changes: True or False.

• False; False

• False; True

• True; False

• True; True

• none of the above

Which statement is False pertaining to the valves of the heart? AV = atrioventricular valves; SL = semilunar valves

• AV prevent backflow into atria when ventricles contract

• AV open when atrial pressure is greater than ventricular pressure

• opening SL produces the second heart sound

• closing of AV produces the first heart sound

• SL open when ventricular pressure is greater than arterial pressure

Which statement is false?

• heart murmurs are due to abnormal heart sounds

• an incompetent valve fails to close properly

• in valvular stenosis the valve fails to open completely

• an incompetent valve fails to open completely

• the left side of the heart pumps with higher pressure

Which of the following statements is true?

• Equal volumes of blood are pumped to the pulmonary and systemic circuits at any moment.

• The right side of the heart is the systemic circuit pump.

• All arteries transport oxygen-rich blood.

• The left side of the heart pumps blood to the lungs.

• All are true

The concentration of K+ is 28X higher inside the cell than outside the cell. If a K+ channel was opened on the plasma membrane, in which direction will K+ flow? This would make the plasma membrane more positive or negative?

• Out of the cell; negative

• Into the cell; positive

• Out of the cell; positive

• Into the cell; negative

• There would be no flow; positive & negative