I would say energy myself, and this is because energy plays a key role in all of these. With trophic levels energy is being transferred amongst the levels. Food chain's is a map of how the energy is passed along the chain. Food web is a web of how energy is transferred, and this is why I would say energy is a keyword.
The difference between the two is that swamps usually have deeper standing water and are wet for longer periods of the year, according to the National Parks Service. Marshes have rich, waterlogged soils that support plant life, according to National Geographic.
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I think the answer is A or D
Answer:
A: Oxygen is a process by which respiration happens.
Explanation:
Cellular respiration converts oxygen and glucose into water and carbon dioxide. Water and carbon dioxide are by- products and ATP is energy that is transformed from the process.
Also:Photosynthesis converts carbon dioxide and water into oxygen and glucose. Glucose is used as food by the plant and oxygen is a by-product. Cellular respiration converts oxygen and glucose into water and carbon dioxide. Water and carbon dioxide are by- products and ATP is energy that is transformed from the process.
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