Questions 1-5. Secondary Consumer. Primary Consumer. 4 th order Consumer. Tertiary Consumer. Producer

FOOD WEB ANALYSIS

Questions 1-5 Producer Primary Consumer Secondary Consumer Tertiary Consumer 4 th order Consumer Remember that arrows point in the direction that food/energy is moving (ie small fish eat zooplankton and squid eat small fish) Producers only have arrows moving away from them

Questions 1b) Producer Primary Consumer Secondary Consumer Tertiary Consumer 4 th order Consumer 1 b) How do producers contribute to the cycling of matter? Producers take inorganic matter from the environment and create organic matter (sugar) through the process of photosynthesis.

Question 6 Why are food chains not a very good representation of the way feeding relationships actually work in nature? Food chains generally show one path of energy/food flow but most ecosystem are more complex and have energy/ food that travel in many different directions.

Question 7 and 8 7) How do decomposers contribute to the cycling of matter? Decomposers take organic materials and break them down into inorganic materials. 8) Why do we rarely see more than 3 rd or 4 th order consumers? There is less and less energy available from one trophic level to the next (only about 10% available). As a result, with increasing trophic levels, there is less of an ability to support higher order consumers (less food to feed them). This means there are fewer 4 th order consumers, and 5 th order consumers and rare.

Question 9 Who is the producer? How do you know? Algae is the producer it only has arrows moving away from it indicating that it produced its own food and is at the bottom of the web. Producers are responsible for injecting energy into an ecosystem

Question 10 Name the organisms that ONLY function as primary consumers. Only small animals and protists. All other primary consumers are also secondary consumers as well.

Question 11 Would a decline in the penguin population affect the elephant seal population? Explain. The elephant seal is not directly affected but both the penguin and the elephant seal are sources of food for the leopard seal. If the penguins decrease, the leopard seal would have to eat more from the other populations therefore causing a drop in their populations

Question 12 How many tropic levels does the cod function at? Explain 3: primary, secondary and tertiary consumer

Question 13 Would a decline in the penguin population affect the leopard seal population? Explain. Not significantly because the leopard seal has other food options.

Question 14 Would a decline in krill have a greater effect on Crabeater seals or Elephant Seals? Explain. The crabeater seals because Krill is the only source of food for the crabeaters.

Question 15 What would be worse for most members of this food web: 1) a major decline in the leopard seal population or 2) a major decline in the Crabeater seal population? The leopard seals would have a greater impact because they are a predator (think population control) for many other populations.

Question 16

Question 17 Why are food webs better than food chains at representing feeding relationships in ecosystems? Food webs show all the different feeding relationships in an ecosystems and show how energy is distributed in many directions from different sources. Shows the diversity and complexity of ecosystems.

Question 18 Can small or large scale disturbances to an ecosystem affect the amount of: a) Biomass present in an ecosystem? A disturbance, such as an oil spill, can cause large scale plant and animal death in the area. This would decrease the amount of biomass present in that ecosystem because there would be less living in the ecosystem.

Question 18 Can small or large scale disturbances to an ecosystem affect the amount of: b) Net Primary Productivity in an ecosystem? A disturbance, such as deforestation, will decrease the amount of primary productivity. Farming with excessive fertilizer run off will increase the amount of primary productivity (eutrophication, which is not necessarily good).