Question

1 kensiah, m.j (1999) pollution impacts on marine biotic communities boca raton crc press llc
amount of ddt per organism
organism\ttrial 1\ttrial 2\ttrial 3\taverage (ddt/organism)
algae\t0.33\t0.33\t0.33\t
minnow\t0.33\t\t\t
sunfish\t0.6\t\t\t
osprey\t0.6\t\t\t
analysis questions:

1. in the space provided below, construct a food chain to illustrate the flow of energy between the organisms used in this simulation.
2. what happened to the amount of ddt per organism as you move up the food chain?

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1. which organism contained the largest concentration of ddt? _________________________

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1. why is ddt harmful to osprey? _____________________________________

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Explanation:

1. In a food chain, energy flows from producers to consumers. Algae are producers (autotrophs), minnow is a primary consumer (herbivore or omnivore eating algae), sunfish is a secondary consumer (eating minnow), and osprey is a tertiary consumer (eating sunfish).
2. DDT is a persistent organic pollutant. Due to biomagnification (the increase in concentration of a pollutant as it moves up the food chain), the amount of DDT per organism increases as you move up the food chain.
3. Based on the concept of biomagnification (as explained in 2), the top - level consumer (osprey) in the food chain would have the largest concentration of DDT.
4. DDT can cause thinning of eggshells in birds like osprey. When osprey consume prey with DDT, the DDT accumulates in their bodies. Thin eggshells are more likely to break during incubation, reducing the survival rate of osprey offspring.

Answer:

1. Algae → Minnow → Sunfish → Osprey
2. The amount of DDT per organism increases as you move up the food chain.
3. Osprey
4. DDT can cause thinning of osprey eggshells, reducing the survival rate of their offspring.