Answer:
The correct answer is "False".
Explanation:
The ventricular systole occurs when pressure rises in the ventricles causing that blood pumps from the right ventricle and into the aorta from the left ventricle. The beginning of this step is given when blood flowing back towards the atria, closing the tricuspid and mitral valves. It is false that the blood flows back towards the relaxed ventricles as it is stated in the question.
1. heat
2. cooling
3.water use
in the earth's atmosphere is made up about approximately 78 percent nitrogen and 21 percent oxygen.
