18 Feb 2016 | 258,249 Views. You may not even associate this with your health, yet it can make a life or death difference. Ignore or defy it, and your risk of death before your 65th birthday jumps 25 percent. Here's the big takeaway message to tell your body for health and longevity.
1 Veins have valves which maintain the unidirectional flow of blood, even against gravity. 2  Since the venous pressure is low (7 mm Hg) the valves are of utmost value in the venous return. However, the valves are absent in: 3  The veins of less than 2 mm diameter.  The venae cavae.
The heart has four valves-one for each chamber of the heart. The valves keep blood moving through the heart in the right direction. The mitral valve and tricuspid valve are located between the between the atria (upper heart chambers) and the ventricles (lower heart chambers).s the left ventricle begins to contract, the aortic valve is forced open. Blood is pumped out of the left ventricle through the aortic valve into the aorta. The aorta branches into many arteries and provides blood to the body. 4. Closed pulmonic and aortic valves.