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.
The heart is a muscular pump that pushes blood through blood vessels around the body. Essential to life, the heart beats continuously, pumping the equivalent of more than 14,000 litres of blood every day. Blood vessels form the living system of tubes that carry blood both to and from the heart.enules take blood from the capillaries to the veins. Veins take blood back to the heart. This constant circulation of blood keeps us alive. Your blood vessels also play a part in the regulation of your blood pressure. Certain chemicals in the body can cause our blood vessels either to contract or dilate.