Chapter 16 Fungi

Characteristics of Fungi 16.1 Characteristics of Fungi Add picture of different fungus

Fungus Comes in many forms Yeast Giant puffballs Mushrooms Mold Pictures of all 4

Yeast Unicellular Fungi Have cell wall, cell membrane, nucleus, large vacuole, membrane organelles. Undergoes cell division

Structure of a mushroom

Cap Protects the spores and aids in their dispersal.

Annulus Marks the site of attachment of the cap before it opens.

Stipe Stalk that supports the cap.

Gills Found on the underside of the cap, produce spores.

Hyphae Tubule filled with cytoplasm and nuclei

Septa Wall that may divide the hypha into segments.

Mycelium Interwoven hyphae that form the entire body of the fungus.

Nutrition Fungi attain food by absorbing it by diffusion from organic molecules found in the environment. Hyphae produce an enzyme that break down large organic molecules into smaller usable pieces. Can break down lignin, which is a major component of wood. Most are saprophyte, absorb nutrients from dead organisms.

Growth Fungi grow extremely fast since nutrients are spread quickly using hyphae. Groups of fungi are not separate organisms, but are generally part of a single fungus connected by the mycelium, which can cover more than a 1000 acres.

16.2 Origin and Diversity of Fungi

Plant like Evolved 400 million years ago from Protista kingdom. Classified in plant kingdom for many years, for this reasons they have divisions instead of phyla. Differences Made of chitin not cellulose Are heterotrophs not autotrophs

Spores Reproductive cells of fungi Can remain dormant or develop into new organisms Mush rooms produce an average of 16 billion spores

Kingdom of Fungi Common molds Club Fungi Imperfect Fungi Sac Fungi

Common Molds Hyphae lack septa, the walls that divide the hyphae into segements

Rhiziods Absorb nutrients and hold common molds to their food source like roots anchor plants to soil. If you cut the mold of a block of cheese, odds are good you missed all of the rhizoids which could be spread through the entire block.

Stolons Connect groups of rhizoids to one another. Transport cytoplasm containing nutrients throughout the fungi.

Zygospore Means tough spores Can survive many years in harsh conditions, when condition are right it starts to grow.

Sac Fungi Diverse division (phyla) that includes yeast, mildew, lichens and morels.

asci Saclike structure that appears during sexual reproduction

Club Fungi Common mushrooms. Almost always reproduce sexually

Basidia a microscopic, club-shaped spore-bearing structure produced by club fungi

Imperfect fungi Reproduce only asexually Athletes foot Ring worm Penicillium

16.3 Fungi in the Biosphere

Lichens any of numerous complex plantlike organisms made up of an alga and a fungus growing in symbiotic association on a solid surface (as a rock)

Mycorrhizae A fungus that grows in association with the roots of a plant in a symbiotic or mildly pathogenic relationship.

Plant disease Some fungi are harmful effects to their host. Rust--plant diseases caused by pathogenic fungi Dutch elm diseases--caused by a member of the sac fungi affecting elm trees, and is spread by the elm bark beetle.

Human Diseases Athletes foots Ringworm Thrush—most found in infants, adults on strong antibiotics' can get thrush.

Human uses Food although many are poisonous Medicine

Fungi in Medicine Penicillin prevents peptidoglycan from cross-linking properly in the last stages of bacterial cell wall synthesis. This greatly weakens the cell wall and causes the bacterium to lyse, or burst open, because of osmotic pressure.