Final answer:
Animals are said to be heterotrophic because they cannot make their own food and depend on other sources for nourishment.
Step-by-step explanation:
Animals cannot make their own food and therefore depend on other sources for nourishment. This makes them heterotrophic organisms. Heterotrophs obtain food by consuming other living entities or organic matter.
An example of a heterotroph is a lion, which obtains its energy by hunting and consuming other animals. Another example is a human, who gets nutrients from eating plants and animals.
In contrast, autotrophic organisms, such as plants, can produce their own food through the process of photosynthesis.
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