41.3.15: Chapter 16
Review Questions
1.
c.
The QRS complex represents ventricular depolarization, which occurs as the electrical impulse moves through the ventricle to prompt contraction.
2.
a.
The right ventricle pumps blood into the pulmonary artery and is subject to increased pressure in clients with pulmonary arterial hypertension.
3.
b.
The coronary arteries supply the heart tissue with blood.
4.
d.
With the exception of the pulmonary artery, all arteries carry oxygenated blood to various tissues for use.
5.
b.
Both ventricles pump nearly simultaneously (ventricular systole). While the ventricles are pumping, both of the atria are filling (atrial diastole). The atria do not pump simultaneously with the ventricles.
6.
a.
The signal starts in the sinoatrial node and passes through the atrioventricular node to get to the ventricles. From there, it travels through the bundles of His and Purkinje fibers.
7.
c.
Automaticity is when the tissue is able to spontaneously generate an action potential, leading to spontaneous depolarization. Tissues with automaticity can act as the pacemaker of the heart.
8.
a.
The ECG gives information about heart rhythm; abnormal rhythms are known as arrhythmias or dysrhythmias. Although some information about structural heart disease can be garnered from an ECG, other diagnostic methods such as echocardiography or biopsy would be needed to confirm the remaining diagnoses.
9.
d.
The SA node, known as the pacemaker of the heart, has the property of automaticity and sends out electrical impulses 60–100 times/minute.
10.
d.
Bradycardia describes a slow heart rate (less than 60 beats per minute), and tachycardia describes a fast heart rate (faster than 100 beats per minute).