Final answer:
Apex consumers are the top consumers in the biosphere, seated at the top of the food chain. They have no natural predators and consume organisms from the lower levels. An example of an apex consumer is the Chinook salmon in the Lake Ontario food chain.
Step-by-step explanation:
In the structure of many ecosystems, apex consumers or organisms at the top of the food chain are the top consumers of the biosphere. In the food chain, primary producers such as photosynthetic organisms (plants or phytoplankton) begin the chain. They are consumed by herbivores which are the primary consumers. Carnivores then eat the primary consumers and are referred to as secondary consumers. This hierarchy continues up to the apex consumers, which have no natural predators and consume organisms from the lower levels.
For instance, in the Lake Ontario food chain, it is Chinook salmon that holds the place as the apex consumer. It's important to understand that the specifics of the food chain can vary based on the ecosystem. However, apex consumers typically consist of large predators across different ecosystems.
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