Aluminum Grades Series 7xxx. Zinc, in amounts of 1 to 8% is the major alloying element in 7xxx series aluminum alloys (7075, 7050, 7049, 710.0; 711.0 etc.), and when coupled with a smaller percentage of magnesium results in heat-treatable alloys of moderate to very high strength.
We previously learned that arteries carry blood away from the heart and that veins carry blood toward the heart. This idea holds true here because we see that the pulmonary arteries are carrying blood away from the heart and the pulmonary veins are carrying blood to the heart. The interesting thing is that in most areas of the body, veins carry blood that is low in oxygen and arteries usually carry blood that's rich in oxygen.
Groups of capillaries within a tissue reunite to form small veins called venules. Venules collect blood from capillaries and drain into veins. Veins are the blood vessels that carry blood back to the heart. They may contain valves which stop blood flowing away from the heart.The heart works by following a sequence of electrical signals that cause the muscles in each chamber to contract in a certain order.lood vessels also play a role in controlling your blood pressure. Blood vessels are found throughout the body. There are five main types of blood vessels: arteries, arterioles, capillaries, venules and veins. Arteries carry blood away from the heart to other organs.