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The Fungi. By: Anesa & Albiona . Characteristics of Fungi . Fungi are non – motile. They release digestive enzymes into their environment. These enzymes break down the dead organic matter than fungi absorbs digestive food through cell wall.
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The Fungi By: Anesa & Albiona
Characteristics of Fungi • Fungi are non – motile. • They release digestive enzymes into their environment. These enzymes break down the dead organic matter than fungi absorbs digestive food through cell wall. • Most fungi are composed of threadlike filaments called hyphae that extend into the environment and absorb nutrients. • Most hypahae have cell walls, from a substance called chitin which strengthens the cell walls of fungi. Spores.
Fungi reproduce both asexually and sexually by means of spores. • During sexual reproduction, genes can be exchanged between fungal strains, allowing the offspring to display variation in traits. • Fungi with spores in a case-like structure are called sporangium, and they are placed in the Zygomycota division. • Fungi with spores in a sack-like structure, are called ascus, and they are placed in the Ascomycota division. • Fungi with spores in a cube-like structure are called basidium, and are places in the Basidiomycota division. Reproduction
Caselike Fungi (Zygomycota) Most fungi in this division are terrestrial saprobes. Hyphae is produced when a mass of mycelium grows. These hyphae are called rhizoids. They support the moulds growth by absorbing water and sugar from the bread. After a few days, black case like structures appear among the hyphae, on the surface of the bread. These structures are known as sporangia. Hyphae spread out and form new mycelium. Bread mould, or Rhizopus, reproduces sexually, by developing two different types of hyphae. When these two hyphae are joined together, they produce a nuclei called a zygospore. Bread Mould Zygomycota
Saclike Fungi (Ascomycota) • In this division, fungi is classified by their formation of a sac structure use din reproduction. • Sac fungi produces two kinds of spores. • Spores produced as a result of sexual reproduction are called ascospores. • Spores produced asexually are called conida. Yeasts • Yeast are unicellular. • Each yeast cell is oval shaped and surrounded by a cell wall. • The cytoplasm contains a large nucleus. • Sometimes yeasts reproduce sexually by forming ascospores. • Yeats can tolerate conditions that lack in oxygen. • Not all yeasts are useful to humans. As some yeasts can cause infections to the skin, lungs, and kidneys. Yeast Fungi
Clublike Fungi ( Basidiomycota) • This division includes mushrooms, puffballs, and yeasts. • The mycelial mass of hyphae forms knobs that absorb water, under damp conditions in soil. • The cap of the mushroom has many gills that radiate out. • When two mycelia are matching mating types, they are shown as red and blue. • When conditions are right, a reproductive structure, the fruiting body forms. • The mushroom is made up of dikaryotic cells. • Parasitic rusts and smuts make up another important group of fungi. They are difficult to control because they have complex reproductive cycles. • Bracket fungi can exist as saprobes on the wood of dead trees. • Puffballs are round shaped fungi. Cap Fruiting body Bracket Fungus Mushroom Puffballs releasing spores.
“Imperfect Fungi” Some species have no known sexual phases, so they cannot be classified into divisions. These species are known as imperfect fungi. Penicillium is considered an imperfect fungi, but has recently been classified as an ascomycete. This chemical inhibited the growth of bacteria and became known as penicillin. Some antibiotics such as penicillin, prevent the formation of cells walls in reproducing bacteria. The common mould tirchophyton rubrum causes a contagious fungal infection called athletes foot. This often occurs between the toes and on the soles of the feet. The symptoms of athletes foot are reddened, cracked, and peeling skin, itching or burning, and stinging sensations. Penicillium Athletes Foot