In an Antarctic marine food web, leopard seals, which feed on birds, fish, and squid,
are carnivores. Phytoplankton are autotrophs that feed krill and copepods. Krill are
eaten by birds and fish, and copepods are eaten by squid and fish.
Based on the food web description provided, which of the following food chains
accurately represents the flow of energy through organisms in the Antarctic
ecosystem?
A. phytoplankton + copepod bird leopard seal
B. leopard seal squid copepod phytoplankton
С. leopard seal squid phytoplankton copepod
D. phytoplankton +copepod squid leopard seal
The Correct Answer and Explanation is:
The correct answer is A: phytoplankton + copepod → bird → leopard seal.
Explanation:
In a food web, energy flows from primary producers (autotrophs) to various levels of consumers (heterotrophs). In the Antarctic marine ecosystem described, phytoplankton serve as the primary producers. They are the foundation of the food web, utilizing sunlight to produce energy through photosynthesis.
- Phytoplankton: These autotrophs are consumed by herbivorous zooplankton such as krill and copepods. In this food chain, we include both copepods and krill as they are part of the primary consumer level, feeding directly on phytoplankton. However, the inclusion of copepods here is more direct as the question focuses on their role in this specific food chain.
- Copepods: These are primary consumers that feed on phytoplankton. In the food chain, they are a crucial link between the primary producers and higher-level consumers. They can also be consumed by squid and fish, but since the food chain specified starts with phytoplankton, the next logical step is to include copepods following them.
- Birds: Birds in this ecosystem feed on krill and copepods. This makes birds secondary consumers that feed directly on the primary consumers of the phytoplankton. Thus, they are represented in the food chain as following copepods.
- Leopard Seals: As apex predators in this ecosystem, leopard seals consume birds, fish, and squid. They are tertiary consumers and form the top of this food chain.
The flow of energy through this food chain correctly reflects the relationships in the Antarctic marine ecosystem. It starts with phytoplankton as producers, flows to copepods as primary consumers, then to birds as secondary consumers, and finally to leopard seals as tertiary consumers. The other options do not accurately represent the flow of energy based on the relationships provided in the description of the food web, either misplacing or omitting key organisms in the energy transfer process.