Answer:
Oxygen
Explanation:
The formula for cellular respiration is oxygen + glucose -> water, carbon dioxide, energy. You can already cross out A and D because they aren't in the formula, so you have two left, water and oxygen. The reason why it is oxygen and not water is because without oxygen you can't even have water. also, I just got this right on my test :-)
In 1665, Robert Hooke observed D. Cell Walls through a microscope!
ECM is the extracellular matrix, or the set of extracellular molecules secreted by cells with the purpose to support surrounding cells. In plants the cell wall is the ECM and in mammals ECM can be in the form of fibrils and may constitute a significant portion of the bulk of the organism and it also referred as connective tissue.
Answer:
It is the sun in most ecosystems as the light energy is fixed during photosynthesis and then transferred to other organisms via the food chain.
Explanation:
I hope it helps
have a nice day
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