Cycling, Changes, and Interactions-Grade 7

Read and answer the following questions. You need to do this in your one note that is part of our Grade 7 notebook.

The cycling of matter is a series of steps in a cycle that allow abiotic elements to be used over and over again. These elements are absorbed and used by producers to form organic matter. Consumers then absorb the organic matter through feeding interactions and use it for growth. As they grow, the consumers produce organic waste. Decomposers break down the organic waste from living and dead organisms into biotic elements that producers can use again.

Example:
When a bear leaves the remains of a salmon carcass in the forest, decomposers break it down into biotic elements, including carbon and nitrogen and other nutrients.

Intereactions and Changes in Ecosystems 

1. What are limiting factors in an ecosystem? Give the definition and three examples. 

2. What are native species? Give the definition and three examples in Canada. 

3. What introduced species? Give the definition and three examples in Canada. 

4. Explain bioinvasion. What are the effects of bioinvasion? 

5. Explain what invasive species are. Give two examples of these types of species in Canada. 

6. Define the term sustainability. 

7.  Research and list three examples of who humans have impacted ecosystems.