Q3 of 95 Page 450

The following graph shows the concentration of oxygen in a river, measured at stations 1.5, each 100 m apart. A sewage outflow is observed just after station 1. At which stations will the concentration of organic matter be lowest?

At 1 and 5 the concentration of organic matter will be lowest because there were no decomposers. Whereas in 2,3 and 4 the decomposers were using the high amount of oxygen to decompose the organic material from sewage.

More from this chapter

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1

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 2

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The smallest amount of energy transferred between organisms and the largest amount of energy lost to the ecosystem is represented by which arrows?


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 5

The diagram shows the organisms in a habitat.


Which of the following indicates the feeding relationships of these organisms?