The natural flow of the blood stream in the human body. (ie: pressure, resistance)
Valves
These are valves, and are found in veins to prevent blood from flowing backwards.
The heart has valves for to allow blood flow in one direction only. They close as the blood passes each. Hooweestik.
No arteries do not contain valves since there is enough pressure from the heart to force blood through these vessels without significant backflow between contractions.
Nothing, it is only pressure that keeps blood moving in the right direction in arteries. Veins have valves that prevent backflow of blood, but arteries do not.
The heart is the organ that keeps the blood flowing. Valves in the heart ensure the flow is only in one direction.
arteries and veins. plus the constant pumping of the blood
Arteries have no valves to prevent the blood from flowing backwards, but it is unnecessary when the heart keeps pumping. The blood pressure is highest when the blood is leaving the heart chamber into arteries -- the heart pumping keeps blood going one-way in the arteries.
Valves are important because they prevent the backflow of blood. This is so the fresh oxygenated blood will not be mixed with the deoxygenated blood as well as the blood running from the pulmonary side will not flow back to the aortic side. The valves keep the blood going in one direction, and that keeps the body stable.
There is a valve in the middle of the heart that keeps the blood going where it is supposed to go. There are also valves in the veins, but that's a different story.
The blood does not accumulate when we are standing as the blood keeps circulating and the valves present in the veins take it back to the heart.
Pressure There are also one way valves in the circulatory system.