Final answer:
Fungi can be heterotrophic, parasitic, and saprophytic, playing crucial roles in decomposition and nutrient cycling. Animals share the heterotrophic and parasitic traits but are not saprophytic like fungi. Fungi's saprotrophic nature makes them essential decomposers in ecosystems.
Step-by-step explanation:
Fungi and animals can indeed be heterotrophic, displaying various nutritional strategies such as parasitism and saprotrophy. Fungi are well-known for being heterotrophic; they do not photosynthesize and must obtain carbon and energy from organic sources. Many fungi are saprophytes, deriving nutrients from decaying organic matter, which is instrumental in nutrient cycling and ecosystem maintenance. Parasitic fungi, on the other hand, rely on living hosts to acquire nutrients, often at the expense of the host's health.
Animals are also heterotrophic, requiring organic substances to obtain energy and carbon as well. Some animal species can be parasitic, exploiting other organisms for food and shelter. However, animals are not saprophytes, as they cannot absorb nutrients directly from decaying organic matter; instead, they consume it as part of their diet.
Saprophytic fungi serve a crucial role in breaking down complex organic substances like cellulose and lignin in dead wood, facilitating the release of nutrients like carbon and nitrogen back into the ecosystem. This decomposition process is vital for ecological balance.