Study GuideBiology–Fungi1. Fungi DefinedFungi, along with bacteria, play a huge role in nature asdecomposers. They help break downorganic material and recycle nutrients back into the environment. Without them, dead plants andanimalswould pile up everywhere.Most fungi aresaprobes, which means they feed on nonliving organic matter such as fallen leaves,rotting wood, and dead animals. Some fungi, however, areparasites. These fungi live on or insideother living organisms and can cause diseases. In fact, fungi are responsible for many plant diseasesthat affect crops, as well as several diseases in humans.1.1 How Fungi Get Their FoodFungi are different from plants and animals because of both their structure and how they obtainnutrients. Instead of eating or photosynthesizing, fungi use a process calledextracellular digestion.Here’s how it works:•Fungi release special enzymes into their surroundings.•These enzymes break down large organic materials into smallermolecules.•The fungi then absorb these small nutrient particles through their cell membranes.This method allows fungi to feed efficiently on a wide range of materials in their environment.1.2 Structure of FungiMost fungi aremulticellular, except for yeast, which is unicellular. The body of a multicellular fungusis made up of tiny, thread-like structures calledhyphae(singular:hypha).•Each hypha is a microscopic filament.•Many hyphae weave together to form a dense network called amycelium(plural:mycelia).Preview Mode
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