The four most abundant elements needed by the human body are carbon, hydrogen, oxygen, and nitrogen because these are needed in large amounts to support our cells, these are referred to as bulk elements.
Oxygen is the most essential element required by our body. The body requires oxygen in the form of gas which is inhaled by the air around us. All the cells in a human body require oxygen which is transported by the blood inside.
Cell is the most basic and fundamental unit of life. It can be of two types: prokaryotic and eukaryotic. Prokaryotic cell is the primitive one with no true nucleus and eukaryotic cell has a true nucleus and all the cell organelles. Generally eukaryotic cells require abundant amount of oxygen.
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The answer to this is rolling friction
B)weathering is the main way phosphorous is recycled
Answer:
Explanation:
Gas exchange occurs at the alveoli in the lungs and takes place by diffusion. The alveoli are surrounded by capillaries so oxygen and carbon dioxide diffuse between the air in the alveoli and the blood in the capillaries.