A&PII Chapter 20 Quiz

Which of the following accurately describes how the fundamental rhythm of the heart is set?

Autorhythmic fibers in the SA node spontaneously depolarize generating rhythmic action potentials.

The _________ side of the heart receives oxygen-rich blood from the lungs and pumps it to the body tissues via the _____________ circuit.

Left; Systemic

Intercalated discs ___________.

1. Are found exclusively in cardiac muscle 2. Are made up of desmosomes and gap junctions 3. Function to physically and electrically connect adjacent muscle cells 4. Allow an action potential generated in one cell to spread throughout the heart

Pick the TRUE statement regarding the cardiac cycle. 1. When pressure in the ventricles exceeds pressure in the aorta/pulmonary trunk, the SL valves open. 2. All four valves are open during isovolumetric contraction and isovolumetric relaxation. 3. The amount of blood contained in each ventricle at the end of ventricular diastole is stroke volume. 4. The AV valves are closed when the heart is relaxed and during atrial systole.

1. When pressure in the ventricles exceeds pressure in the aorta/pulmonary trunk, the SL valves open

Pick the TRUE statement concerning the valves of the heart. 1. The aortic valve is also known as the mitral valve. 2. The papillary muscles and chordae tendineae function to prevent prolapse/eversion of AV valves. 3. The semilunar valves are one-way inlets from atria into ventricles. 4. The first heart sound is due to the SL valves opening. 5. The pulmonary valve and aortic valve are classified as atrioventricular valves.

2. The papillary muscles and chordae tendineae function to prevent prolapse/eversion of AV valves.

Which of the following would be expected to slow heart rate? 1. Cardiac accelerator nerve 2. Vagus nerve 3. Epinephrine 4. Thyroid hormone 5. Fever

2. Vagus nerve

Which of the following is a correct sequence of blood flow through the heart? 1. Left atrium, pulmonary valve, pulmonary trunk, pulmonary arteries 2. Pulmonary veins, capillaries of the body tissues, pulmonary arteries, left atrium 3. Coronary sinus, right atrium, tricuspid valve, right ventricle, pulmonary valve 4. Right ventricle, bicuspid/mitral valve, Left ventricle, aortic valve, ascending aorta

3. Coronary sinus, right atrium, tricuspid valve, right ventricle, pulmonary valve

The visceral layer of the serous pericardium is also called the _____________.

Epicardium

_____________ increases stroke volume, thereby increasing cardiac output.

Increased filling/stretch of the heart (preload)

The T wave of the ECG represents ___________, which leads to __________ (mechanical event).

Ventricular repolarization; ventricular diastole