Whenever we see stale bread or fruits turning mouldy, fungi are at work..........we also understand that fungi, like most other living things, have their usefulness and harmfulness too.

Whenever we see stale bread or fruits turning mouldy, fungi are at work. When trees die and their dead trunks start to decompose, fungi are the masterminds. Most of us tend to associate fungi with the decomposition of dead plants or animals. In actual fact, fungi can also attack living things.

The fungi that cause decay are known as the Saprobe. They are actually yeasts which feed on the dead remains of plants and animals. While they can be anuisance in the kitchen, as they turn our food bad, Saprobe can also assist man. For instance, by breaking down the dead bodies of plants and animals, these leftovers are removed from the living world. In addition, yeasts can be used to make wine, beer and also as raising agents in bread.

The parasitic fungi are the ones which feed on living things. The powdery mildew, downy mildew or rust are the few which attack plants. Usually, these fungi deposit themselves on the leaves or flowers of the plants. Their hyphaes (slender, feeding branches) then squeeze themselves into the gaps between the plant's cells and soak up their nutrients. After which, a hard, black fruiting body called the ergot is left in the flower replacing the seeds. The ergot contains toxins which causes serious illnesses if eaten. Despite its poisonous nature, the ergot contains active ingredients which when purified and used in small amounts, are treatments for migraine. Parasites attacking living animals, especially man, are rarer as most animals have their own immune system. In special cases like an AIDS patient, where his immune system is very weak, parasites may find their chance to attack.

The most aggressive kind of fungi is the predatory ones. As the name suggests, they catch and feed on their preys, usually smaller than themselves. Some predatory fungi dwell in ponds to catch amoebae or rotifers. In capturing the amoebae, the fungi use their sticky hyphaes to hold down the creatures before feasting on them. To capture rotifers, the fungi usually hide among the algae, stretching out their sticky hyphaes again. An unaware rotifer which mistakes one of the hyphaes as the blob of the algae will grab it, only to find itself trapped and absorbed by the fungi. Some predatory fungi which live in the soil, set traps to capture victims like the nematodes.

Thus we see that fungi are not only the ones which turn our food mouldy. Besides these, there are also other kinds. In addition we also understand that fungi, like most other living things, have their usefulness and harmfulness too. 

Summary: Saprobe, also called yeasts, are fungi which turn our food bad. They also help to decompose dead remains of plants and animals and also acts as ingredients for wine, beer and bread. Parasitic fungi attack and suck the nutrients of plants, depositing an ergot in place of the seeds in the flowers after that. The ergot can cause illness when eaten raw but when purified and taken in moderate amounts, help cure migraine. Parasitic fungi seldom attack animals because of their defensive immune system. The predatory fungi which sometimes live in waters or on algae in ponds or even in the soil, set traps to capture their victims, usually smaller than themselves, before feasting on them.