Consider the Following Marine Community: Sea Otters Prey on Sea

question 34

Multiple Choice

Consider the following marine community: Sea otters prey on sea urchins and therefore help maintain a healthy sea urchin population. Sea urchins prey on kelp. By helping to maintain viable sea urchin populations, the sea otters are also allowing enough kelp to grow and act as a habitat for other organisms.
-Suppose that a bacterial infection swept across a sea otter population and killed most sea otters before they could reproduce. How would the marine community be affected?

• A) For a period of time, there would be overpopulations of sea urchins and therefore a decline in kelp populations.
• B) For a period of time, there would be an overpopulation of kelp and therefore a decline in sea urchins.
• C) Sea otters would continue to decline until they reached extinction.
• D) Kelp would become a primary predator of sea urchins.

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Definitions:

Control Group

In research, a control group is a group of subjects not exposed to the experimental treatment, used as a benchmark to measure the effect of the treatment.

Independent Variable

A variable that is manipulated in an experiment to see its effect on a dependent variable.

Observational Group

A group in a study that is exposed to the variable under investigation for observational purposes without receiving the experimental treatment.

Independent Variable

In experimental research, the variable that is manipulated by the researcher to observe its effect on the dependent variable.