1. RELATIONSHIPS IN MARINE ECOSYSTEMS

2. Energy Flow Sunlight – main energy source for life on Earth. Goes through ecosystem in one direction, from sun or inorganic compounds, to autotrophs (producers), and then to various heterotrophs (consumers) Producers: autotrophs (plants, some algae, and certain bacteria) capture energy from sunlight or chemicals and make their own food Consumer- all heterotrophs: they rely on food containing the sun’s energy (producers)

3. Trophic Levels Each step in a food chain or web Producers are on the 1 st trophic level and consumers are 2 nd or higher levels. Each consumer depends on trophic level below it for energy.

4. Feeding Relationships Food Chain: Simple model showing the steps in which organisms transfer energy by eating and being eaten. Shows only one pathway of energy Food Web: All feeding relationships among various organisms in an ecosystem. Form a network of complex interactions and show all pathways of energy Predation – one organism captures and feeds on another organism. (predator/prey) Predator – does the killing Prey – one that is killed

5. FOOD WEBS

6. Type of relationshipSpecies harmed Species benefit Species neutral Mutualism Commensalism Parasitism = 1 species Symbiosis: Two species live closely together

7. Mutualism: Beneficial to Both species Examples: boxing crab and sea anemone cleaner shrimp lichens on rocks

8. Commensalism: One benefits and other is not helped nor harmed Examples: Pilot fish and sharks Emperor shrimp and sea cucumber Polar bears and cyanobacteria

9. Parasitism: One organisms lives on or inside another and harms it Examples: Lampreys/leaches isopods trematodes