3The Characteristics of Fungi Eukaryotes - true nucleus and other organelles present.Non-Photosynthetic organismsMost fungi are multicellular heterotrophs (can’t make own food)Cell wall present, composed of cellulose and/or chitin.Food storage - generally in the form of lipids and glycogen.Fungi can be both microscopic and macroscopic – common macroscopic varieties are molds and mushroomsAll fungi require water and oxygen to grow & reproduce.Fungi grow in almost every habitat imaginable, as long as there is some type of organic matter present and the environment is not too extreme.
4Saprophytes or saprobes - fungi feed on dead tissues or organic waste (decomposers) Fungi can sometimes attack the tissues of living plants and animals and cause disease.Fungi disease is a major concern for humans because fungi attack not only us but also our food sources, making fungi competitors with humans for nutrientsMold spores can cause mild to serious allergies. Spores can be airborne , be inhaled, and trigger an allergic reaction
6Molds Rapidly growth Asexual spores Many human importances Food spoilageFood productsAntibiotics, etc.A mold is a rapidly growing, asexually reproducing fungus.The mycelia of these fungi grow as saprobes or parasites on a variety of substrates.Also used in foods (Blue cheese, Tempeh) and in industrial production of drugsEarly in life, a mold, a term that applies properly only to the asexual stage, produces asexual spores.Later, the same fungus may reproduce sexually, producing zygosporangia, ascocarps, or basidiocarpsSome molds go through a “fake sex” processNoble Rot - BotrytisFig Antibiotic activity
8Fungi are Spore-ific!!!Spores - asexual (product of mitosis) or sexual (product of meiosis) in origin.Purpose of SporesAllows the fungus to move to new food source.Resistant stage - allows fungus to survive periods of adversity.Means of introducing new genetic combinations into a population
9Reproduce by spores Spores are reproductive cells Sexual (meiotic in origin)Asexual (mitotic in origin)Fungi reproduce by releasing spores that are produced either sexually or asexually.The output of spores from one reproductive structure is enormous, with the number reaching into the trillions.Dispersed widely by wind or water, spores germinate to produce mycelia if they land in a moist place where there is food.Penicillium hyphae with conidiaPilobolus sporangiaAmanita fruiting body
10Sac fungi diversityThis begins the first of several photographic reviews of fungal diversity. Enjoy the pictures and try and get a feeling of some of the different forms these fungi take and their roles in the environment.
12Yeasts Single celled fungi Adapted to liquids Plant saps Water films Moist animal tissuesBread and wine yeast, the budding yeast, SaccharomycesEasily cultured. For a time, this was the most important organism for studying the molecular genetics of eukaryotesThus, Saccharomyces is arguably the most important organism known to humansCandida causes diseases of humans, usually experiencing chemical imbalance or immune problemsCandidaSaccharomyces
13HUMAN-FUNGUS INTERACTIONS Beneficial Effects of FungiDecomposition - nutrient and carbon recycling.Biosynthetic factories. Can be used to produce drugs, antibiotics, alcohol, acids, food (e.g., fermented products, mushrooms).Model organisms for biochemical and genetic studies.Harmful Effects of FungiDestruction of food, lumber, paper, and cloth.Animal and human diseases, including allergies.Toxins produced by poisonous mushrooms and within food (e.g., grain, cheese, etc.).Plant diseases.
14Fungal Infections Athlete's Foot Athlete's foot, also called tinea pedis, is a fungal infection of the foot. It causes peeling, redness, itching, burning, and sometimes blisters and sores.Athlete's foot is a very common infection. The fungus grows best in a warm, moist environment such as shoes, socks, swimming pools, locker rooms, and the floors of public showers. It is most common in the summer and in warm, humid climates. It occurs more often in people who wear tight shoes and who use community baths and pools.
15What Causes Athlete’s Foot? Athlete's foot is caused by a microscopic fungus that lives on dead tissue of the hair, toenails, and outer skin layers.What Are the Symptoms of Athlete's Foot?Signs and symptoms of athlete's foot vary from person to person. However, common symptoms include: Peeling, cracking, and scaling of the feetRedness, blisters, or softening and breaking down of the skinItching, burning, or both
16How Is Athlete's Foot Treated? Athlete's foot is treated with topical antifungal medication (a drug placed directly on the skin) in most cases. Severe cases may require oral drugs (those taken by mouth). The feet must be kept clean and dry since the fungus thrives in moist environments.How Is Athlete's Foot Prevented?Steps to prevent athlete's foot include wearing shower sandals in public showering areas, wearing shoes that allow the feet to breathe, and daily washing of the feet with soap and water. Drying the feet thoroughly and using a quality foot powder can also help prevent athlete's foot
18Ringworm What is ringworm of the skin? Ringworm of the skin is an infection caused by a fungus.Jock itch is a form of ringworm that causes an itchy rash on the skin of your groin area. It is much more common in men than in women. Jock itch may be caused by the spread of athlete's foot fungus to the groin.What causes ringworm?Ringworm is not caused by a worm. It is caused by a fungus. Grow best in warm, moist areas, such as locker rooms and swimming pools, and in skin folds.Ringworm is contagious!. It spreads when you have skin-to-skin contact with a person or animal that has it. It can also spread when you share things like towels, clothing, or sports gear.You can also get ringworm by touching an infected dog or cat, although this form of ringworm is not common
19What are the symptoms?Ringworm of the skin usually causes a very itchy rash. It often makes a pattern in the shape of a ring, but not always. Sometimes it is just a red, itchy rash.Jock itch is a rash in the skin folds of the groin. It may also spread to the inner thighs or buttocks.Ringworm of the hand looks like athlete's foot. The skin on the palm of the hand gets thick, dry, and scaly. And skin between the fingers may be moist and have open sores.
20How is ringworm of the skin diagnosed? If you have a ring-shaped rash, you very likely have ringworm. Dr. will probably look at a scraping from the rash under a microscope to check for the ringworm fungus.How is it treated?Topical creams
21To prevent ringworm:Don't share clothing, sports gear, towels, or sheets. Wash your clothes in hot water with special anti-fungus soap.Wear slippers or sandals in locker rooms and public bathing areas.Shower and shampoo well after any sport that includes skin-to-skin contact.Wear loose-fitting cotton clothing. Change your socks and underwearKeep your skin clean and dry.If you have athlete's foot, put your socks on before your underwear so that fungi do not spread from your feet to your groin