I need an answer to the above question for my nearly impossible anatomy packet. Thanks : )
2007-10-17 16:30:25 · 7 answers · asked by loveisanabstractnoun 2 in Science & Mathematics ➔ Medicine
Veins need valves to create pressure to pump the blood to the heart. Blood flows away from the heart and, therefore, the pressure is not required.
Simplistically, think of the effort it takes to run up a hill, and and how much easier it is to run down it.
2007-10-17 16:35:15 · answer #1 · answered by concerned neighbor 5 · 2⤊ 0⤋
Do Veins Have Valves
2016-10-02 00:27:24 · answer #2 · answered by ? 4 · 0⤊ 0⤋
Why is not a good question to ask in science. The answer will always be because it IS!
As you know Arteries move blood away from the heart and veins bring the blood back after going through the capillaries.
However the reason for valves in the veins is because it assists in the oneway upward movement of blood from the lower portion of the body, because nothing is forcing it to return to the heart except for body movements and the values.
There is no need for values in the arteries once it gets out of the heart because the blood pressure created by the heart pumping is what causes its movement.
2007-10-17 16:36:43 · answer #3 · answered by Ort B 3 · 3⤊ 2⤋
valves are the openings in the heart and are only provided in veins and not in arteries. Since veins have to carry de-oxygenated blood from the body to the heart with high pressure
2015-07-31 03:30:04 · answer #4 · answered by Tasneem 1 · 0⤊ 1⤋
valves in your veins are the coolest things ever. your blood has to fight gravity to get back to your heart.
one thing happening is that your muscles in your legs (for example) constrict and relax as you walk - the constricting muscle pushes the blood up your veins - the valves close behind the gush of blood to keep the blood from flowing back down again.
This process is repeated and your blood inches it's way back to your heart (although I think it moves faster than "inching").
So, if you have a damaged valve, the blood keeps flowing back down into your foot (for example) and then your foot swells.
The most coolest thing is to have a Doppler study done of your veins. If you have get the chance, ask the Dr to place the wand on one of your valves - and then tense your stomach muscles. Your valve will shut and block the blood. It is really amazing... everyone should try.
2007-10-17 17:23:38 · answer #5 · answered by thyroider 2 · 1⤊ 1⤋
Veins has valve to prevent the back flow of deoxygenated blood to the organ because veins carry blood away to the organs, while artery has to caryy blood along the gradient hence doesnot hv valves.
2007-10-19 00:00:11 · answer #6 · answered by KS 26 2 · 0⤊ 1⤋
Theoretical venous pump pressure changes with posture and tone of muscles.. So veins need valves to prevent regurgitation.
Arteries supply blood with systemic blood pressure. So arteries do not need valves.
2007-10-17 17:53:05 · answer #7 · answered by J.SWAMY I ఇ జ స్వామి 7 · 0⤊ 1⤋