1. Mutualism ~ When both organisms benefit.
Egyptian Plover and crocodile
2. Commensalism ~ Only one organism benefits but the other remains neutral
Bird nest and Tree
3. Parasitism ~ Only one organism benefits and the other is harmed;
Dog and Ticks
Answer:
d. Citric acid cycle
Explanation:
The only process in the list that requires the presence of O2 in order to occur is the Citric acid cycle or Krebs cycle. This cycle is part of the aerobic cellular respiration and it occurs only when O2 is available. If there is no oxygen, an alternative process that could happen is fermentation, but this is only carried by some microorganisms and some cells such as muscle cells.
In fact, oxygen is not needed by citric acid cycle but it is by the next step: the electron transport chain. In this chain, oxygen is the final acceptor of electrons, and without oxygen, the Krebs cycle doesn't occur because the final electron transport chain can't be done.
*protein is an essential nutrient that covers more than 50 percent of you body weight.