The body system that directly provides for this demand is the circulatory system. When you exercise, the circulatory and muscle system cooperate, in order to meet the increased needs for strength and energy. The circulatory system involves the network which delivers blood to every part of your body. This flowing of blood ensures that the tissues are oxygenated and rich in necessary nutrients. During exercise, more blood flows to and from your muscles, in order to deliver the necessary amounts of oxygen to complete the aerobic respiration.
Eutrophication occurs due to excessive use of these compounds, which can lead to having dead zones in bodies of water.
Dead zones refers to areas with decreased levels of oxygen in the bodies of water caused by eutrophication and other factors. These affect the marine life negatively as fishes are also dependent on oxygen.
Eutrophication is defined as the presence of excess minerals in the water, which causes dense growth of plants and leads to depletion of oxygen that make the animals in the water to die.
The wind is just strong enough to move the sand grains which were sorted by size by the wind. Heavier grains were left in place where as smaller grains were carried away. These grains kept moving till they were concentrated in one place usually up a hill. The grains climb the flat slope on the windward side and then fall off the steep side. The dunes may migrate slowly as this process continues, the grains at the upwind side climb the dune with the help of the wind and then fall down the downwind side.<span>
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Answer:
A piloted spacecraft is always manned
