| A | B |
|---|
| because their needs are met. | Organisms survive in their environment |
| Describes organisms that interact | grass makes oxygen, animals use it |
| Balance an ecosytem with too many rabbits | more foxes that eat rabbits |
| This describes a balanced ecosystem | No animal or plant drives out other animals or plants. |
| cause an ecosystem to change quickly. | Earthquakes |
| Impact of a parasite on an ecosystem | hurts one organism & helps another |
| When an ecosystem like a lake changes to a field or forest | Succession has occurred |
| If the main prey for an organism gets sick or dies | The number of predators would decrease |
| If a fish fossil is found in a desert | Scientist know that it was once a lake or sea |
| an owl & hawk succeed even though they are food competitors | One hunts at night, the other during the day |
| Building houses | can disturb the environment. |
| An animal can become extinct | if its habitat is destroyed. |
| cause-climate change from rainy to dry | effect-a change in kinds of plants & animals |
| cause-The U.S. established National Parks | effect-to preserve nature's beauty & habitats for plants and animals |
| Damage from strip mines | can be repaired by mining companies if they replace soil. |
| parasite-host relationship | the parasite uses the host for food & harms it. |
| ways a flood can affect an entire ecosytem | water kills the grass, grass eating organisms move/die, meat eating organisms then have food shortage |
| Dinosaurs | species that are now extinct |
| hazardous waste | poisonous & disease causing trash. |
| Succession | still occurring in the Mt. St. Helen's volcano erupted environment |
| competition | Wolves & coyotes use the same resources in their environment. |
