\begin{tabular}{l}\( \begin{array}{l}\text { In lichens, fungi provide food } \\ \text { for algae and algae provide } \\ \text { food for the fungi. }\end{array} \) \\ \hline\end{tabular}

Did you know that lichens are actually composite organisms formed from the symbiotic relationship between fungi and algae (or cyanobacteria)? This partnership is so successful that lichens can survive in extreme environments, from bare rock to arid deserts. The fungi provide a protective structure and absorb moisture, while the algae/photosynthesizers generate nutrients through photosynthesis – it's a classic case of teamwork making the dream work in nature! In the real world, lichens play a crucial role in the ecosystem! They contribute to soil formation, break down rock surfaces, and even serve as indicators of air quality. Because they are sensitive to pollutants, such as sulfur dioxide and heavy metals, scientists often use them to monitor environmental health. So next time you spot a lichen, remember it's a mini ecosystem with a big impact!