N.+Fungi+(31)

= **__TARGET I: MASTERY OF FUNGI DIVERSITY AND CLASSIFICATION__** =

**//Chapter 31//** 1. Identify and describe characteristics for members of Kingdom Fungi. 2. Describe alternation of generations as it relates to a typical fungus. 3. Identify the importance of fungi ecologically, economically, and medicinally. 4. Identify & describe the distinguishing characteristic(s) of the following three fungi clades: Zygomycota, Ascomycota and Basidiomycota.

= = = 1. Identify and describe characteristics for members of Kingdom Fungi. = //Fungal Basics and Importance//

Fungi is a kingdom of organisms that are **heterotrophic** (not autotrophic like plants) and consume their energy via absorption of extracellular objects. They do this by excreting enzymes outside of the organism that break down dead and living tissues, or soil that surrounds it. There are approximately 1.5 million species of fungi and their importance to this world is often understated. Without fungi and detritivorous (decomposer) bacteria there would be no waste recycling and life would not exist in the same capacity. There are 5 different phyla of fungi but the 3 major phyla that contain the most species of fungi are zygomycetes (various molds, parasites, etc.) and are identified by their extracellular plasma secretion that cover the bread or fruit and slowly digest it. The next phyla is ascomycetes with over 65,000 species and are also known as sac fungi; they are known for their sexual and asexual reproduction via mass spore releases from ascocarps in the from of asci "tubes" that hold the spores until dispersal. The final major phyla of fungi is basidiomycetes with over 30,000 species and is the iconic fungus. Included in basidiomycetes are the traditional mushroom that are the sexual apparatus of the underground body (covered after this). Fungi are primarily decomposers but also function as mutualists, pathogens, and medical tools; which develops their importance to the global ecosystem.

//Fungal Structure// Multicellular fungi are composed of filaments known as hyphae, which may be either __septated__ or __coenocytic__.

media type="youtube" key="w8M4hK57vxM" width="425" height="350"

//**Fill in the blanks**//

(1) Coenocytic cells forgo a portion of the cell cycle. What is this portion of the cell cycle and what is the effect?

(2) Chitin strengthens the cell wall to provide the rigidity of fungi, through an interwoven mass of__called a__(a chitin monomer: differs from cellulose by_-containing group__)__

(3) Fungi feed on their surroundings by secreting enzymes to_organic matter. To allow for greater absorptive potential, the fungi maximizesby increasing the length of the hyphae, but not the width. Some hyphae perform specialized functions, most notably the hyphae which interact with, also called, of mycorrhizae.

1) Septated fungi have cells in the hyphae divided by crosswalls (septa), with pores large enough to allow for transport of organelles such as ribosomes and mitochondria between cells. Coenocytic fungi have no such septa, instead forgoing cytokinesis and hence having a continuous cytoplasm between the cells of the hypha. 2) hyphae; mycelium; nitrogen 3) hydrolyze; surface area; roots; haustoria
 * Answers:**

= 2. Describe alternation of generations as it relates to a typical fungus. =



Great General and Basic Overview of Reproduction in Fungi media type="youtube" key="lTAO5i4Zb6w" height="315" width="560" Another Overview on Reproduction of Fungi

media type="youtube" key="qDwgSWDqKoQ" height="315" width="420" =

= = 3. Identify the importance of fungi ecologically, economically, and medicinally. = **Ecologically** Fungi As ** Decomposers ** ** Mutualism **
 * Fungi Keep ecosystem stocked with inorganic material for plant growth › Without fungi carbon nitrogen and other elements would be tied up in organic matter
 * metabolize dead organisms and other waste products, making their molecules available to other creatures.
 * ** Endophytes ** **-**live inside leaves or plants which create toxins that deter herbivores or by increasing host plan tolerance of heat drought, or heavy metals.
 * ** Symbiosis- ** Some fungi share digestive services with animals which help break down plant material in the stomach.
 * ** Lichens- ** is a mass of hyphae that hold individual photosynthetic cells

**Economically** ** Pathogens ** ** Food **
 * Chestnut blight, pine pinch canker, rye disease
 * Fungal infections is called mycosis
 * Ringworm disease
 * Yeast infections
 * Molds
 * Creation of cheeses, colas, yeast, alcohol, bread, mushrooms, truffles

**Medically** Fungi used to stop internal bleeding after childbirthAntibiotics
 * ** Penicillium **
 * **Cyclosporine-** suppress immune system after organ transplants


 * The Impacts of Fungi**

They are pathogens in certain things for instance athletes foot Fungi and bacteria are the principal decomposers. Fungi and bacteria help break down complex polysaccharides and proteins into simple organic compounds. By doing this they help provide materials that plants are able to use to perform photosynthesis. Fungi help decompose food, and wood which can actually increase the fitness of species of animals that can differentiate between a healthy fruit and a rotting one because of the fungus present in decomposition. Mushrooms are a fungus. We could eat only ceratain ones because some are poisonous. One such mushroom includes Agaricus, which is well known in North America. Fungus includes yeast. So a certain type of yeast is saccharomyces cervisiae. This yeast helps make bread, beer, wine, etc.. They are sources of gallic acid, gluconic, pencillin, ethyl alcohol, etc.. Considering the magnitude of materials and their diversities that industry utilizes today, this is not surprising. Fungi is the basis of many of the staples of modern life from soap, to the production of battery acid, to the medical industry that is at the heart of the healthcare debate raging in congress today. They are used in medicines. We use them for antibiotics, which are really important to us because we need them to help treat illnesses. Their use can be as small as curing minor rashes and burns to potentially becoming a cure for major illnesses like cancer
 * 1) Pathogens**
 * 2) Decomposers**
 * 3) Spoilers**
 * 4) Food**
 * 5) Industrial uses**
 * 6) Medicine**

= 4. Identify & describe the distinguishing characteristic(s) of the following three fungi clades: Zygomycota, Ascomycota and Basidiomycota. =

Basically, it's: Spore → germination → mycelium → plasmogamy → heterokaryotic stage → karyogamy → zygote → meiosis → spore producing structures → spore


 * Phylum Zygomycota** (zygomycetes)-


 * Multicellular land fungi living in the soil or decaying organic matter. Mostly **saprophytic** some **parasitic** on plants and insects.
 * Divided into three to seven classes according to different schemes of classification.
 * One group forms **mycorrhizae** with the roots of plants.
 * **Coenocytic mycelium** with septa separating the reproductive structures.
 * Asexual spores formed in sporangia.
 * Sexual spores formed the fusion of hypha endings called gametangia. The fused tips develop into a **zygosporangium**, which in turn will produce **zygospores**.
 * Mating types or strains required in some for conjugation to occur: **heterothallic** species.
 * **Chitin** in cell wall; no cellulose present.
 * About 1000 species described. The common bread mold is a zygomycete.




 * Phylum Ascomycota** (sac fungi)
 * Multicellular or unicellular fungi.
 * Terrestrial fungi
 * Four classes recognized by many mycologists.
 * Hyphae are narrower than the Zygomycota and are generally septate and **multinucleated**.
 * **Chitin** present in cell wall; cellulose absent.
 * Asexual spores are conidia produced at a hypha tip, the **conidiophore**.
 * This phylum has a **dikaryon** in the ascogenous hyphae.
 * This phylum is characterized by a sexual state composed of **ascospores** within sac-like **asci** (sing. ascus).
 * Haploid mycelia of sac fungi form **antheridia** (male) and **ascogonia** (female) as they approach a mate. Plasmogamy occurs between them. Karyogamy is delayed.
 * The ascogonium leads to dikaryotic hyphae that are fused into the ascocarp.
 * The **asci** (sing. ascus) are contained within (or on) a variety of **ascocarps.**
 * Karyogamy occurs within the asci.
 * Important parasites and saprophytes. Yeasts are unicellular ascomycetes. Many edible species. Lichens are a mutualistic association of an algae and a fungus. About half of the ascomycetes are involved in a lichen association or in mycorrhizae.
 * About 65,000 species described.




 * Phylum Basidiomycota** (club fungi)
 * Multicellular fungi.
 * Terrestrial fungi.
 * Two or three classes are recognized.
 * Well developed mycelium
 * Hyphae are narrower than the Zygomycota and typically septate.
 * Two phases in the life cycle: monokaryotic and a dikaryotic phases.
 * They have a prolonged binucleate **dikaryotic stage**, which is maintained by use of clamp connection.
 * Sexual spores are called **basidiospores.** Basidiospores are produced through meiosis.
 * Meiotic basidiospores are formed externally on the differentiated hyphal tips (**basidia**),which are usually the site of nuclear fusion and meiosis.
 * Important saprophytes and parasites. Many edible species. Mushrooms, puffballs, shelf fungi, toadstools, rusts, smuts, stinkhorns, etc.
 * About 30,000 species.

Short Ascomycetes quiz !

media type="custom" key="11996311" width="63" height="63"

Overviews of this Target Detailed overview of the entire unit! Answers to the Target Questions

CAMBELL OUTLINE Practice 1. [|32 Cards to Practice] 2. [|35 Cards to Practice] 3. : Has only questions to think about, no answers 4. : 10 Questions and AnswersLIN


 * Fill in the blank. Answer choices below; Answers can be used more than once or not at all. Highlight to see the answers.**
 * If you can correctly answer all the questions, you are SET for alternation of generations and general reproduction for fungi!! :D**


 * haploid || yeasts || diploid || meiosis || karygomy || mitosis || plasmogamy || phermones || zygote || mycelium ||
 * asexual || spores || hyphae || germinate || sexual || molds || genetic || mycorrahizae ||= cell division || heterokaryotic ||

At the beginning of __ sexual __ reproduction, the __ hyphae __ of two mycelium release sexual signaling molecules called __phermone__s. If the mycelia are of different mating types, the hyphae meet and fuse. This union of the cytoplasms of two parent mycelia is called __ plasmogamy __. The hyphae before were __ haploid __, meaning they had only one nucleus. After this though, the resulting mycelium is __ heterokaryotic __because the nuclei have not yet fused. After this, the mycelia undergoes __ karygomy __, in which the nuclei are fused, resulting in a __ zygote __. This is the only __ diploid __ (2n) stage in most fungi. __ Meiosis __ leads to the formation of spores, restoring the __ haploid __ conditions. The spores are then dispersed. Spores __ germinate __ when they land in favorable conditions, and the cycle starts again. The sexual processes of karygomy and __ meiosis __ generate extensive __ genetic __ variation. In __ asexual __ reproduction, many fungi reproduce by groing filmentous fungi that produce spores by __ mitosis __; these species are informally called __ molds __. These species are able to grow rapidly and produce many spores. Some fungi reproduce asexually by growing as single-celled __ yeasts __, which reproduce by ordinary __ cell division __ or pinching off small bud cells off of the parent cell.

More Review Materials

1. [|Jeff Yoshimura]: This is another review of the entire unit Scroll down to Fungi and Plant Diversity Click on Ch. 31 pg.616-619 and pg.629-631.doc 2. []Brief overview of some areas that we've discussed 3. []: Goes into detail about Basidiomycota, Zygomycota, Ascomycoa Has some questions and solutions as well 4.