Question

below is a food web from an ocean ecosystem in monterey bay, off the coast of california. which two of the following arrows show matter moving from a secondary consumer to a tertiary consumer? the arrow between the kelp and the kelp bass the arrow between the sea urchin and the sea otter the arrow between the plainfin midshipman and the kelp bass the arrow between the kelp and the sea urchin the arrow between the black rockfish and the kelp bass

Explanation:

1. First, recall trophic levels: Producers (e.g., kelp, phytoplankton) are level 1. Primary consumers (eat producers) are level 2. Secondary consumers (eat primary consumers) are level 3. Tertiary consumers (eat secondary consumers) are level 4.
2. Analyze each option:

• Kelp (producer) to kelp bass: Producer to primary/secondary? Kelp is producer (level 1), so this is producer to consumer (not secondary to tertiary). Eliminate.
• Sea urchin (primary consumer, eats kelp) to sea otter: Primary to secondary (sea otter eats primary), not secondary to tertiary. Eliminate.
• Plainfin midshipman: Let's see its diet. If plainfin midshipman is a secondary consumer (eats primary consumers like zooplankton or phytoplankton - related), and kelp bass eats it, then plainfin midshipman (secondary) to kelp bass (tertiary). This is secondary to tertiary.
• Kelp (producer) to sea urchin (primary): Producer to primary. Eliminate.
• Black rockfish: If black rockfish is a secondary consumer (eats primary or secondary? Let's assume it's secondary), and kelp bass eats it, then black rockfish (secondary) to kelp bass (tertiary). This is secondary to tertiary.

So the two arrows are between plainfin midshipman and kelp bass, and between black rockfish and kelp bass.

Answer:

• the arrow between the plainfin midshipman and the kelp bass
• the arrow between the black rockfish and the kelp bass