Exam 7: The Peripheral Nervous System: Efferent Division

Parasympathetic stimulation slows the rate of depolarization of the SA node and thus decreases the heart rate.

Normally, the stroke volume of the right side of the heart is the same as the stroke volume of the left side of the heart.

Describe the cardiac cycle.

Match the anatomical structures, labelled e., with the heart characteristics. (Options may be used more than once or not at all.)a. through a.tricuspid valve b.myocardium c.aortic semilunar valve d.AV node e.sinoatrial node -electrically connects the atria to the ventricles

Match the factor involved in the initiation and spread of cardiac excitation, labelled d. with the description. (Options may be used more than once or not at all.)a. through a.SA node b.AV node c.bundle of His and Purkinje system d.gap junction -the only point of electrical contact between the atria and ventricles

Gap junctions are absent between atrial and ventricular cells.

The ____________________ is the volume of blood in the ventricle when filling is complete.

Sympathetic stimulation increases the heart rate.

Match the terms, labelled a. through f., with the descriptions. (Options may be used more than once or not at all.) a.stroke volume b.end-diastolic volume c.cardiac output d.heart rate e.end-systolic volume f.sympathetic activity -The number of times the heart contracts each minute is the_____.

Which of these statements correctly describes action potentials in the heart?

The function of the chordae tendineae and papillary muscles is to hold the AV valves wide open during diastole to ensure complete ventricular filling.

If the cardiac output is 4800 mL/min and the heart rate is 60 beats per minute, what is the average stroke volume in millilitres?

The pulmonary circulation carries oxygenated blood from the lungs to the body tissues.

An increase in cardiac sympathetic activity ____________________ the velocity of impulse conduction through the heart.

Match the term, labelled a. through g., with their correct characteristic. a.gap junction b.HDL c.functional syncytium d.heart valve e.pericardial sac f.LDL g.adenosine -Indicate the proper order of the events during the cardiac cycle by placing numbers in the blanks preceding the events in sequence. The first and last events are already indicated as a guide. 1__ AV valve open; aortic valve closed; ventricular filling occurring _____ blood ejected from the ventricle _____ isovolumetric ventricular relaxation _____ atrial contraction _____ aortic valve opens _____ SA node discharges _____ ventricular filling complete _____ ventricular relaxation begins _____ aortic valve closes _____ isovolumetric ventricular contraction _____ ventricular contraction begins; AV valve closes _12__ AV valve opens; ventricular filling occurs again; one cardiac cycle is complete

Which of these statements correctly describes the refractory period of cardiac muscle?

Match the term, labelled a. through g., with their correct characteristic. a.gap junction b.HDL c.functional syncytium d.heart valve e.pericardial sac f.LDL g.adenosine -induces coronary vasodilation

The cardiac output is the same as the cardiac reserve of the heart.

Which of the following describes blood returning from the lungs?

Match the pressure relationships, labelled e., with the times in question. (Options may be used more than once or not at all.)a. through a.aortic pressure > ventricular pressure > atrial pressure b.ventricular pressure > aortic pressure > atrial pressure c.aortic pressure > atrial pressure > ventricular pressure d.ventricular pressure > atrial pressure > aortic pressure e.atrial pressure > ventricular pressure > aortic pressure -during isovolumetric ventricular contraction