1
Part A: design a food chain with four trophic levels, and identify the organism in each level. Part B: Can humans ever occupy the lowest, or first, trophic level?

2
One example of ecological interaction in the ocean is the relationship between boxer crabs and sea anemones. In this unique relationship, the crabs "wear" the stinging anemones on their claws as an extra level of protection from predators. The anemones are then free to eat any leftovers from the crab's meal.
Part A: Identify which type of symbiotic relationship the above example is. (1 point)
Part B: In a parasitic type symbiotic relationship, one species of the pair is harmed. Make a fictional change to one of the members of the boxer crab/sea anemone relationship so that it becomes a parasitic relationship. Describe what that change is. (3 points)