3.1 The Fungi Learning Goals: Describe characteristics of fungi Major differences from plants Source of energy Types of reproduction Physical structure of fungi (mycelium with hyphae, chitin in cell walls) Describe the diversity of fungi Characteristics of molds, yeast, and mushrooms Phylogeny of fungi (to which kingdoms are they closely related?)

General Characteristics of Fungi 1. Mostly Multi-cellular Key Terms Hyphae (singular: hypha) Body made up of cells linked end to end in long tubes Develop from spores

General Characteristics of Fungi Key Terms Mycelium An extensive branched network of hyphae The individual hyphae in a mycelium are specialized to a specific task, be it anchoring the fungus to its food source, invading and digesting the food source, or building reproductive structures.

General Characteristics of Fungi 2. Inside the Hyphae In some varieties of fungi, walls called septa divide the hyphae into individual multinucleated cells. Septa are usually porous, letting material flow between the cells unobstructed. Other fungi have no septa and consist of a single multi-nucleated cell (more than one nucleus)

General Characteristics of Fungi 3. Fungal cells consist of cell walls. The cell wall do not contain cellulose (like plants), but instead, chitin, a complex carbohydrate. (also found in some animals)

General Characteristics of Fungi 4. Heterotrophic (similar to animals) Fungi must obtain food from their environment by extra-cellular digestion. Specialized hyphae grow into the food source, and release digestive enzymes designed to break down the complex organic molecules into smaller, easier to manipulate molecules. The small molecules diffuse into the hyphae and are carried through the cytoplasm to where they are needed.

General Characteristics of Fungi 5. Store energy as glycogen 6. Different feeding relationships – Fungi obtain food through different relationships with their ecosystems: Saprophytes decompose wastes Mutualists form symbiotic relationships with other living things (both organisms benefit) Parasitic fungi attack and digest living cells – parasitic fungi have a unique type of hyphae, the haustoria, which is used to penetrate and grow inside host cells.

General Characteristics of Fungi 7. Asexual Reproduction in Fungi Fragmentation – when pieces of a mycelium are broken from the structure, more often than not, the pieces will each spawn a new mycelium. Budding – unicellular yeasts use a process called budding, which is similar to mitosis

General Characteristics of Fungi 8. Reproduction by Spores When spores are located in an environment featuring favourable growing conditions, they begin to form new mycelium In some fungi, specialized hyphae grow away from the mycelium and form a specialized structure called a sporangium. This structure is created for the sole purpose of growing and housing spores before they are let loose.

General Characteristics of Fungi 8. Reproduction by Spores Most sporangia protect their spores from drying out before their release. Almost all fungi produce spores in huge numbers to overcome the very high spore failure rates. Fungal spores are often tiny and lightweight. These attributes allow them to be carried effectively by the wind, or hitch a ride on some unsuspecting host.

Life Cycle of a Mushroom

Life Cycle of Black Bread Mold

Diversity of Kingdom Fungi 1. Zygomycotes Common Name: Case-like fungi Example: Rhizopus (molds on bread and…)

Diversity of Kingdom Fungi 2. Ascomycotes Common Name: Sac-like fungi Example: Morels, truffles, yeasts, lichens

Diversity of Kingdom Fungi 3. Basidomycotes Common Name: Club-like fungi Example: White button mushrooms

Diversity of Kingdom Fungi 4. Deuteromycotes Common Name: Imperfect fungi Example: Penicillin Products: blue veined cheese, soy sauce (No sexual stage in their life-cycle)

Diversity of Kingdom Fungi 5. Chytridomycotes Common Name: chytrids Example: potato warts (found in PEI in 2007), most are aquatic – only fungi with swimming spores (flagellum attached)

Mutualism – Mycorrhizae and Lichens Is the name given to the mutualistic relationship formed between basidiomycotes or zygomycotes with plants. The hyphae from the fungus provide the plants with increased mineral and water absorption. The fungus, in turn, receives a portion of the plant’s carbohydrates.

Mutualism – Mycorrhizae and Lichens Lichens are the product of a mutualistic relationship between fungi and algae The fungi portion of the lichen provides water and minerals, while the algae do the actual food production. Needing only water, minerals and light, lichen are some of the most robust organisms on the planet. They often pioneer new environments, too harsh for plants or fungi to live alone.

Homework Read pg. 80-85 Pg. 85 #1, 5 and 8 Kingdom Fungi Worksheet (in pkg)