| A | B |
|---|
| abyss | deepest part of the ocean |
| barriers | something that stops the migration from one area to another |
| competition | occurs when more than one organism works to get what it needs to live |
| dark zone | just below twilight zone, no light extremely cold water and severe pressure |
| ecosystem | all the interactions between the living and nonliving things in an environment |
| migration | movement from one area to another for more resources and room |
| niche | organisms role in an ecosystem |
| phytoplankton | tiny plant like organisms that float at or near the water surface |
| pioneer stage | first stage of succession in which plants grow very well |
| succession | the process in which new plant and animal populations replaces old plant an animal populttains over time |
| sunlit zone | upper area of the ocean where seasonal changes influence water temperature |
| twilight zone | just below the sunlit zone, so very little light plants cannot carry on photosynthesis |
| zooplankton | tiny animal like organisms in the ocean that eat plantlike organims |
