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Scientists removed all viruses from a seawater sample and then measured the growth of the plankton population in the water.
They expected the rate to increase dramatically, but the population actually got smaller.
To explain this result the answer should indicate why the plankton declined when viruses were removed from a sample of seawater.
Which one of the following, if true, most helps to explain the unexpected result described above?
Viruses in seawater help to
This suggests that the removal of viruses should benefit plankton making the decline in the plankton population more confusing.
9% picked this
Plankton and viruses in seawater
This makes viruses and plankton competitors. If the relationship between the two organisms were competition, it would be expected that a setback for one would benefit the other.
1% picked this
Plankton utilize the nutrients released
Why this is right
This suggests that the removal of viruses would deprive plankton of nutrients.
Skill tested: Paradox · how this choice captures the argument's function is the move to repeat next time.
79% picked this
The absence of viruses can
Without knowing that bacteria flourished in the seawater sample discussed and that the bacteria caused harm to the plankton this answer doesn’t go far enough to show why the plankton population declined when the viruses were removed.
10% picked this
At any given time, a
This explains the drop in the population of plankton but does not explain the observed negative growth rate. This answer does not explain why the plankton population declined after the viruses were removed.
2% picked this
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