Energy cannot be destroyed or created and an organisms energy must go somewhere and come from somewhere.
Answer:
Positive
Explanation:
A proton carries a positive charge
respitory systym and circulatory system because you need your lungs to breathe and the blood and heart to pump the oxygen into the blood. :))
Answer:
Animals and plants need nitrogen to build amino acids in proteins, which are the building blocks of life. Unlike oxygen, nitrogen cannot be absorbed directly from the air by animals and plants.
Explanation: