| A | B |
|---|
| Runoff | Can be a threat to an estuary |
| barnacle | Organism that attaches to grasses or rocks |
| plankton | base (lowest) of marine food web |
| Organisms in estuaries | These adapt to changes in salinity & water level |
| Shallow, coastal waters | Where most of marine organisms are found |
| Nutrient trap | Where fresh water & salt water mix in estuaries |
| Coral reef | Ecosystem found in shallow, tropical seas |
| The ocean | Where most of the nutrients in an arctic ecosystem come from. |
| Corals | Use stinging tentacles to capture prey |
| Over fishing | This is a threat to ocean organisms |
| Salt marsh | Marine ecosystem dominated by marsh grasses |
