1) Define primary productivity. What factors control primary productivity and biomass in the oceans (Section 12.9). Discuss bottom-up and top-down control and why understanding these principles is important to understanding changes (e.g. global, seasonal) in primary productivity. Finally, describe the role of primary producers in food webs and food chains in the ocean (e.g. trophic pyramids Figure 12.30). Describe what would happen in ocean food webs and chains if primary producers were reduced or removed from the trophic structure.
(2) From the diagram on page 301 in the text explain WHY most of the living organisms in the ocean are in the top layer (Epipelagic zone). Also discuss why there are fewer animals living in near or on the deep ocean floor. What are the limiting factors in the deep ocean layers and floor? (Some help – Read the section on page 363 about whale falls and be sure to read thru Chps 11 & 12. There is also an attached article – What Lies Beneath the Deep Gulf)

(3) Most reef-building corals have communal algae actually living inside the flesh of the corals. Please name these symbiotic algae and tell what limiting factor their presence in corals give the coral animals in terms of where they can grow. Where are coral reefs found (e.g. specifically global region and why this region)? Why are reefs limited to a particular region (factors controlling reef development and growth). Compare and contrast shallow versus deep water coral reef systems. Use this link to help you get started – http://www.coris.noaa.gov/about/deep/