Answers+Ecology+Review

toc =Ecology Exam Review - ANSWERS=

1. What is an [|ecosystem]. Give 2 examples.

//The interaction of a community of organisms with their environment. e.g. forest, farmer's field, pond//

2. What is an [|abiotic] factor? Give 2 examples.

//The non-living components of an environment,// **//not//** //produced through the action of living things. e.g. wind, water, tornadoes, sand//


 * //Note://** //a bird's nest is a BIOTIC factor, not an ABIOTIC factor!//

3. What is a [|biotic] factor. Give 2 examples.

//Something that affects living things that is living itself or a product of a living organism. e.g. bird's nest, viral disease, predation, competition, humans, grizzly bears//

4. What is a producer? Give an example.

//An organism that produces its own food (in the form of sugar) from sunlight and inorganic molecules through the process of photosynthesis. e.g. plants (all types)//

5. What is a [|decomposer] ? Give an example?

//Is an// //organism that breaks down dead or decaying organisms. e.g. worms, bacteria, fungi//

6. What type of organism is in the:

1st trophic level = //producer, e.g. plants// 2nd trophic level = //herbivore, e.g. rabbit// 3rd trophic level = //carnivore, e.g. fox// 4th trophic level = //top carnivore, e.g. wolf//

7. A consumer is...

//An organism that eats another organism. e.g. rabbit, fox, wolf.//

8. What is bioaccumulation?

//Bioaccumulation is when an organism eats toxins (harmful chemicals) faster than it can eliminate the toxins.//

9. What is the primary source of energy for all living things?

//The Sun and the visible light that the Sun emits.//

10. Name the 2 important bacteria found in the nitrogen cycle and then indicate the purposes of each.

//Nitrogen-fixing bacteria. These bacteria take nitrogen gas (N 2 ) from the atmosphere and turn it into a solid, nitrogen-containing compound that plants (producers) can use to grow and make protein.//

11. Show the differences & similarites between photosynthesis & respiration. You may use a venn diagram to show this.

//H// //2// //O + CO// //2// //+ visible light => C// //6// //H// //12// //O// //6// //+ O// //2// //Captures energy from sunlight and stores it in glucose for LATER use by the organism Occurs only in light Occurs only in plants Occurs only in chloroplasts//
 * //Photosynthesis only://**

//Both involve H// //2// //O, CO// //2// //, C// //6// //H// //12// //O// //6// //and O// //2// //. Both involve energy stored in glucose Photosynthesis is the reverse of cellular respiration//
 * //Common://**

//C// //6// //H// //12// //O// //6// //+ O// //2// //=> CO// //2// //+ H// //2// //O + release of energy Energy stored in glucose is used by organism to do things (e.g. human running). Occurs any time, day or night Occurs in plants, animals and fungi Occurs in mitochonria//
 * //Cellular respiration only://**

12. Which process removes carbon dioxide from the air?

//Photosynthesis.//

13. What is an organic compound? Give an example.

//An organic compound is a molecule that contains carbon and hydrogen. e.g.// //C// //6// //H// //12// //O// //6//

14. Which gas makes up the majority of our atmosphere?

//Nitrogen, N 2 //

15. What gas do humans breathe out?

//Carbon dioxide, CO 2 //

16. All matter cannot be //created// or //destroyed// but is continuously recycled.

17. Give two (2) sustainable activities performed by humans.

//Cutting forests sustainably, farming.//

18. What can people do to help an ecosystem regain balance after it was affected by human activity.

//Replant trees, re-introduce species, restore habitat so that it can support an extinct species again.//

19. Name two human activities that can negatively affect an ecosystem.

//Cutting forests, polluting rivers, introducing alien species//

20. Why/when does competition occur?

//Competition occurs when two different organisms require the same resource.//