It's called hypoxemia, it's low levels of oxygen in the blood, to be more specific, it's oxygen loss in your blood from your arteries. It can cause respiratory disorders, and tissue hypoxia, as a result of the blood not providing much oxygen to your body.
I hope I helped :)
The answer is c because the earth not only is tilted it orbits
<span>a. Fish have a single central heart; earthworms have several hearts.
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Multi cellular organisms are made up of billions of cells each specialized to a unique role and these cells are organized into structural and functional units such as tissues and organs.
For each cell and organ to function optimally, it requires oxygen and nutrients and needs carbon dioxide and metabolic waste taken away in a continuous, never ending process.
<span>A mechanism is needed to accomplish the important function of transporting the relevant materials to and from the cell. The circulatory system fits this bill splendidly. It is a specialized organ system which allows blood and lymph to flow through the entire body carrying nutrients such as glucose, amino acids and electrolytes as well as oxygen to each cell, at the same time carting away carbon dioxide and all sorts of metabolic waste over to excretory organs to be expelled from the body.
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I believe that the food web is more stable
