In a food web, primary consumers are organisms that eat primary producers (like phytoplankton and kelp), while secondary consumers are organisms that eat primary consumers.
In the options given, the arrows that show matter moving from a primary consumer (zooplankton and sea urchin) to a secondary consumer (black rockfish and kelp bass) are:
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The arrow between the zooplankton and the black rockfish - This shows the zooplankton (a primary consumer) being eaten by the black rockfish (a secondary consumer).
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The arrow between the plainfin midshipman and the black rockfish - If plainfin midshipman are considered a primary consumer, and if they are eaten by the black rockfish, this would also denote matter transfer from a primary consumer to a secondary consumer.
Thus, the correct arrows are:
- The arrow between the zooplankton and the black rockfish.
- The arrow between the plainfin midshipman and the black rockfish (depending on the role of the midshipman in the food web).
If you are only looking for definite primary to secondary consumer transfers, then stick with the first option listed.