First 202 words of the document:
Rearrange the statements into the correct order.
1. Blood enters the right and left atria from the vena cava and pulmonary
The atria relax (atrial diastole), and the ventricles contract (ventricular
systole) from the base.
The electrical impulse travels to the AV node and down the Bundle of His
to the base of the ventricles.
When the pressure gets higher than the pressure in the ventricles, the
atrioventricular valves open, and the ventricles fill.
The SAN sends an electrical impulse across the atria walls.
Blood is forced up into the pulmonary artery and aorta by the right and
left ventricles respectively.
The ventricles relax (ventricular diastole), and the pressure in the arteries
close the semilunar valves.
The arteries expand due the elastic fibres in their walls, then the smooth
muscle contracts as a reflex (peristalsis).
Pressure in the ventricles is higher than the atria and the arteries, the
atrioventricular valves close and the semilunar valves open.
The cardiac muscle in the atria contract (atrial systole), and pressure
11. Blood is circulated through the lungs and body.