Parasitism and autotrophism
I think the correct answer from the choices listed above is option A. It is the alveoli that is composed of single layer <span>surrounded by a network of capillaries. These are used to allow oxygen and carbon dioxide to move from the lungs to the bloodstream.</span>
<em><u>Answer:</u></em>
<em><u>epipelagic zone</u></em>
<em><u>Explanation:</u></em>
<em><u>The epipelagic zone is home to most organisms because it is the sunlit upper layer of the ocean. it is also know as the photic or euphotic zone</u></em>
Bigeochemical cycles are variety of biological, geological, and chemical processes.
Many elements cycle through ecosystems,
organisms, air, water, and soil. Many of these are trace elements. Other elements, including carbon, nitrogen, oxygen, hydrogen, sulfur, and phosphorus are critical components of all biological life.
Because these elements are key components of life, they must be available for biological processes. The biogeochemical cycles transport and store these important elements so that they can be used by living organisms.
hope this helps!
Do you mean "why"?
They are the main source for all living organisms because they provide energy, relatively short term, for any creature that consumes them.
