Quiz Questions

Which of the following factors would increase cardiac output: (1)increased venous return, (2)Increased sympathetic stimulation,(3)increased parasympathetic stimulation,(4) increased heart rate?

1,2

If the connection between the SA node and AV node becomes blocked, the ventricles will beat faster than atria T/F

False

if the connection between the vagus nerve and the heart is cut, pacemaker cells in the SA node will depolarize more slowly, the heart will decrease the rate of beating and cardiac output will decrease. T/F

False

Blood pressure increase if parasympathetic system is activated T/F

False, decrease

Which of the following factors, if any would decrease heart rate: 1) increased sympathetic stimulation,2)decreased parasympathetic stimulation,3)increase blood levels of epinephrine, 4)faster depolarization of pacemaker cells in the SA node?

None

Acetylcholine slows the heart because it opens ____ channels and causes the membrane of pacemaker cells to depolarize more ______

Pottasium, Slowly

What is the function of the papillary muscles in the heart? Contractions of the papillary muscles

Prevent the atrioventricular valves from reversing into the atria

List of heart chambers and vessel that are associated with the heart. Place in order 1.right atrium 2.left atrium 3.right ventricle 4.left ventricle 5.venae cavae 6.aorta 7.pulmonary trunk 8.pulmonary veins.

5,1,3,7,8,2,4,6

Intercalated discs serve to transfer electrical signals and the force of contraction from cell to cell. T/F

True

In cardiac muscle, the fast depolarization phase of the action potential is the result of (increase or decreased?) memrane permeability to ________ (name) ions

Increase, Sodium ions

How would heart rate and stroke voulme change if carotid and aortic baroreceptors slow their discharge

both heart rate and stroke volume increase

The long plateau phase of the cardiac muscle action potential is due to

calcium channels remaining open.

If the pacemaker cells in the SA node become more permeable to potassium ions, the pacemaker cells will

hyperpolerize and heart rate will decrease

The final destination for blood collect by cardiac viens is the

right atrium