Question

A bacterium provides essential amino acids to an aphid, which in turn provides sugars to the bacterium. Assuming that each partner is benefiting from the interaction, this would be an example of a _______ mutualism.

1) trophic
2) metabolic
3) service
4) chemical

Answer 1

The symbiotic relationship between a bacterium and an aphid, where they benefit from an exchange of nutrients, is an example of (2) metabolic mutualism. The correct option is (2)

Step-by-step explanation:

The interaction you are describing between a bacterium and an aphid, where the bacterium provides essential amino acids to the aphid and in turn receives sugars, is an example of metabolic mutualism. In metabolic mutualism, two organisms exchange metabolic products that are beneficial to each other. This type of mutualistic interaction involves a direct transfer of nutrients and substances between two species, allowing them to thrive in their respective environments and is different from trophic interactions, which generally involve one organism consuming another, or service mutualism, which typically involves an exchange of services, like protection for food. The most accurate answer from the choices provided would thus be (2) metabolic.

Examples of mutualism are seen across various ecosystems and species. One example is the relationship between termites and protozoa, where the protozoa digest cellulose that termites cannot, while they get a secure environment and a constant food supply. Another instance is lichens, composed of a symbiotic relationship between a fungus and photosynthetic algae or bacteria, where the fungus provides structure and protection while the algae or bacteria produce glucose as nourishment.