OCN 201 Twelfth Reading Discussion Questions

Marine Life and the Marine Environment II

Trujillo and Thurman - Chapter 12

12.3 How Many Marine Species Exist?

1. Which percentage of the known species on Earth are marine species? (Also see fig. 12.7)

Why Are There So Few Marine Species?

2. Explain why there are relatively few marine species.

Species in Pelagic and Benthic Environments

3. Give the percentages of marine species that are benthic compared to those that are pelagic. (Also see fig 12.7)

4. Explain why 98% of marine species are benthic.

12.4 How Are Marine Organisms Adapted for the Physical Conditions of the Ocean?

5. Explain why terrestrial organisms have complex plumbing systems compared to marine organisms.

12.5 What Are the Main Divsions of the Marine Environment?

6. List the two main marine environments. (Also see fig. 12.21)

Pelagic (Open Sea) Environment

7. List the two primary pelagic provinces. (Also see fig. 12.21)

8. Define the neritic province. (Also see fig. 12.21 and p. 528)

9. Define the oceanic province. (Also see fig. 12.21 and p. 529)

10. List the oceanic province's four biozones. (Also see fig. 12.21)

11. Define the epipelagic. (Also see fig. 12.21 and p. 522)

12. Define the mesopelagic. (Also see fig. 12.21 and p. 527)

13. Define the bathypelagic. (Also see fig. 12.21 and p. 518)

14. Define the abyssopelagic. (Also see fig. 12.21 and p. 517)

15. Give the single most important factor that determines the distribution of life in the oceanic province.

16. List the three pelagic zones based on the availability of sunlight. (Also see fig. 12.21)

17. Define the euphotic zone. (Also see fig. 12.21, fig. 12.22, and p. 522)

18. Define the disphotic zone. (Also see fig. 12.21, fig. 12.22, and p. 521)

19. Define the aphotic zone. (Also see fig. 12.21, fig. 12.22, and p. 517)

Epiphotic Zone

20. Explain why oxygen concentration begin to decrease below 200 m. (Also see fig. 12.22)

Mesopelagic Zone

21. Define the oxygen minimum zone (OML). (Also see fig. 12.22 and p. 529)

22. Give the depth range of the OML. (Also see fig. 12.22)

Bathypelagic and Abyssopelagic Zones

23. Which percentage of the ocean is the aphotic zone?

24. Explain why most deep-water animals are predators.

25. Explain why oxygen concentrations increase below the OML. (Also see fig. 12.22)

Benthic (Sea Bottom) Environment

26. Define the supralittoral. (Also see fig. 12.21 and p. )

27. List the two benthic provinces. (Also see fig. 12.21)

28. Define the subneritic province. (Also see fig. 12.21 and p. 533)

29. Define the suboceanic province. (Also see fig. 12.21 and p. 533)

Subneritic Province

30. List the two subneritic zones. (Also see fig. 12.21)

31. Define the littoral zone. (Also see fig. 12.21 and p. 526)

32. Define the sublittoral. (Also see fig. 12.21)

33. Define the inner sublittoral. (Also see fig. 12.21 and p. 524)

34. Define the outer sublittoral. (Also see fig. 12.21 and p. 528)

Suboceanic Province

35. List the three suboceanic zones. (Also see fig. 12.21)

36. Define the bathyal zone. (Also see fig. 12.21 and p. 518)

37. Define the abyssal zone. (Also see fig. 12.21 and p. 517)

38. Define the hadal zone. (Also see fig. 12.21 and p. 523)