4.1 Species, communities and ecosystems

1.In an area of forest measuring 100 m by 100 m, samples were taken to estimate the number of silver maple (Acer saccharinum) trees in the forest. The number of trees counted in each of five areas of 400 m2 was recorded. Approximately how many silver maple trees are in the 10000m2 area of forest?

2. Cladograms can be created by comparing DNA or protein sequences. The cladogram on the left is based on DNA sequences and the cladogram on the right is based on comparing protein sequences.   What is the reason that cladograms based on DNA sequences are more reliable predictors of the phylogenetic relationship of species than cladograms based on protein sequences?

3. The bacterium Neisseria gonorrhoeae causes infections related to the human reproductive system. The graph shows the percentage of samples in which this bacterium showed resistance to six antibiotics over a period of ten years. What is a possible explanation for the total percentage resistance being larger than 100% in 2010?

4. The image shows a transect through a stream and a field. Which calculation would test for the association between two species of plants from quadrat data from section A and section B of the field?

5. What is the classification of an organism that is able to make organic compounds from inorganic nutrients?

6. Which are characteristics of a species? I. The potential to interbreed to produce fertile offspring II. The formation of a population with members of the same species within a community III. The overproduction of offspring

7. Two populations of the same fish species were fed different diets to investigate the effect of differing nutrition on their growth. What is an appropriate method to determine the significance of a resulting difference?

8. The image shows a female Golden Orb-weaving spider (Nephila plumipes). They can grow as large as 4 cm and build webs strong enough to trap small birds for food.   Which of the following describe(s) this spider? I. Primary consumer II. Heterotroph III. Arthropod

9. Image I shows a spotted hyena (Crocuta crocuta) and image II shows a leopard tortoise (Geochelone pardalis). Based on their diet, the feces of spotted hyenas appear white because of high calcium content. Leopard tortoises eat hyena feces. What would explain such tortoise behaviour?

10. Two populations of the same fish species were fed different diets to investigate the effect of differing nutrition on their growth. What is an appropriate method to determine the significance of a resulting difference?

11. Which of the following describe(s) this spider? I. Primary consumer II. Heterotroph III. Arthropod

12. Which statement describes the term species?

13. The image shows an Arctic food web. What is the role of the Arctic hare?

14. What is a population?

15. Which pair of statements is correct?

16. What is an ecosystem?

17. What term can be used to describe clams that eat decaying plant matter?

18. In ecosystems the amount of energy that passes from one trophic level to the next is called the conversion efficiency. What is the average conversion efficiency from primary to secondary consumers in most ecosystems?

19. What is the mode of nutrition of midge larva?

20. Which represents a correct food chain from this web?

21. In a pond, two species of fish feed on insects and worms. The insects feed on the green plants that live in the water. What constitutes a population in this ecosystem?

22. What best describes the mode of nutrition of a heterotroph?

23. What term refers to organisms of the same species, living in a specified area and time?

24. In a pond, two species of fish feed on insects and worms. The insects feed on the green plants that live in the water. What constitutes a population in this ecosystem?  

25. The fungus Calocera viscosa obtains its nutrients from decaying conifer trees. Which pair of terms describes C. viscosa’s nutrition?

26. What best describes the mode of nutrition of a heterotroph?

27. Which of the following trophic groups include fungi?

28. Which term best defines a group of populations living and interacting with each other in an area?

29. Which of the following is the best definition of a population?

30. Which of the following ecological units includes abiotic factors?