Phytoplankton, shown on the left in the image below, are microscopic organisms that can be found in freshwater and salt water environments. They perform photosynthesis to get energy and act as an important food source for larger organisms, such as the whale that is shown on the right. Phytoplankton A large whale. Which characteristic describes the whale but not its food source, the phytoplankton? The whale is heterotrophic. The whale has cell walls. The whale is unicellular. The whale is a prokaryote.

The whale is heterotrophic.

Explanation:

All living organisms require energy for their life processes. In nature, this energy source is obtained by feeding on one another. When one organism eats another, it gets energy. In this case, a large whale is described to be reliant on a photosynthetic phytoplankton for its energy source.

The phytoplankton is capable of producing its own energy source (food) via the process of photosynthesis. Hence, making it an autotrophic organism. However, since the large whale is dependent on the phytoplankton for food/energy source, it is regarded to be heterotrophic i.e. incapable of producing its own food, hence, depends on other organism like phytoplankton in this case.

the answer to your question is sperm

more words for this could be abiotic and biotic

abiotic: living organisms within an ecosystem

biotic: non-living organisms within an ecosystem