Cardiovascular System 3, Heart, electrical system

The electrical activity for the contraction of the heart is initiated by the:
a. sinoatrial node 
b. atrioventircular node
c. medulla oblongata
d. myocytes

The only point of electrical conduction between the atria and the ventricles is provided by the;
a. Sinoatrial node
b. Atrioventricular node
c. Atrioventricular bundle 
d. Purkinje fibres

The electrical impulses from the atrial myocardium are collected by the
a. Sinoatrial node
b. Atrioventricular node   
c. Atrioventricular bundle
d. Purkinje fibres

Sympathetic stimulation of the heart will 
a. Increase heart rate 
b. Reduce heart rate
c. Have no effect on heart rate
d. Reduce stroke volume

Parasympathetic stimulation of the heart is provided via the;
a. Phrenic nerves
b. Thoracic spinal nerves
c. Cervical spinal nerves
d. Vagus nerve

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