Table of Contents
What is the function of the venous system?
The peripheral venous system functions both as a reservoir to hold extra blood and as a conduit to return blood from the periphery to the heart and lungs.
What is the venous circulation system?
The venous circulation consists of an interconnected system of veins and sinuses. Venous outflow from the cerebral hemispheres occurs via cortical veins within the pia mater on the surface of the brain as well as deep central veins. Cortical and deep veins may empty into the superior sagittal sinus.
What role do venous valves play?
Venous valves take blood back to the heart against the force of gravity. Venous valves are especially important in the arms and legs as they prevent the backflow of blood in response to this pull of gravity.
What does the venous system consist of?
Grossly, the venous system is composed of venules and small and great veins, which serve to return blood from tissues to the heart (see the image below).
Where are venous areas of the body?
Deep veins, located in the center of the leg near the leg bones, are enclosed by muscle. The iliac, femoral, popliteal and tibial (calf) veins are the deep veins in the legs. Superficial veins are located near the surface of the skin and have very little muscle support. The great saphenous vein is a superficial vein.
Why are valves important in veins?
Unlike arteries, veins contain valves that ensure blood flows in only one direction. (Arteries don’t require valves because pressure from the heart is so strong that blood is only able to flow in one direction.) Valves also help blood travel back to the heart against the force of gravity.
How many valves are there in veins?
In your veins there are one-way valves that are placed about one inch apart that keep blood flowing in the right direction. When your leg muscles relax, the valves inside your veins close preventing the backward flow of blood back down the legs.
Why are veins important in the circulatory system?
They arise or are formed from venules which are small vessels carrying deoxygenated blood from the capillaries in tissues. The pressure through veins is much lower than that of arteries and as a result of this veins have valves within them to prevent backflow of blood that may arise as a result of gravity.
Why are muscles important in the venous system?
The one-way valves in deep veins prevent blood from flowing backward, and the muscles surrounding the deep veins compress them, helping force the blood toward the heart, just as squeezing a toothpaste tube ejects toothpaste. The powerful calf muscles are particularly important, forcefully compressing the deep veins in the legs with every step.
How is the venous system different from the arteries?
What is the venous system? Veins are a type of blood vessel that return deoxygenated blood from your organs back to your heart. These are different from your arteries, which deliver oxygenated blood from your heart to the rest of your body. Deoxygenated blood that flows into your veins is collected within tiny blood vessels called capillaries.
How does the one way valve in the deep veins work?
The deep veins play a significant role in propelling blood toward the heart. The one-way valves in deep veins prevent blood from flowing backward, and the muscles surrounding the deep veins compress them, helping force the blood toward the heart, just as squeezing a toothpaste tube ejects toothpaste.