Answer:
oxygen
Explanation:
cells use to produce energy during cellular respiration
Hibernation is an adaptation that helps animals to survive cold winters.
Hope this helps.
Answer:
Dead zones are hypoxic (low-oxygen) areas in the world's oceans and large lakes, caused by "excessive nutrient pollution from human activities coupled with other factors that deplete the oxygen required to support most marine life in bottom and near-bottom water. (NOAA)".
Explanation:
