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					Biology 204          LAB 5: FUNGI
OBJECTIVES
Learn the names and taxa (mostly called "classes" in textbooks) and structures of common fungi.
Figure out how mushrooms reproduce--learn the first hand-out in lectures; then (during lab), make sure you understand
the variations found in other fungi.
Try to develop a mature understanding of botanical and mycological reproduction.
Try to develop a mature understanding of the ecological, economic, and medical importance of fungi.


BACKGROUND INFORMATION

A. SEX:              INTRODUCTION TO BOTANICAL REPRODUCTION.
Before you get into the lurid details of reproductive habits of the various life forms, make sure you review
1. SOME DEFINITIONS, which you were supposed to have learned in the prerequisites for this course

    haploid = 1n = 1 set of chromosomes with genes made of DNA

    diploid = 2n = 2 sets of chromosomes with the same types of genes, although the two genes may be different alleles.
     In a diploid human, for instance, two chromosomes will have genes for eye color but the allele [=gene version] on
     one of the chromosomes may be for blue color, while the allele on the other chromosome may be the DNA code
     which leads to brown color. The genes for eye color would always be on the same location on matching
     [=homologous] chromosomes.

 syngamy = fertilization = conception = part of pollination in seed plants: 2 haploid gametes ---> 1 diploid zygote.
[usually the beginning of a new individual]

    mitosis = normal cell division with daughter cells all genetically identical to each other and to the parent cell:
                haploid cell ---> 2 genetically identical haploid daughter cells
                diploid cell ----> 2 genetically identical diploid daughter cells

 meiosis = division occurring only once during a life cycle, usually in reproductive organs:
diploid cell ---> 4 haploid daughter cells, not with identical DNA, each with half the parental genes and half the
parental chromosomes.

    recombination = part of meiosis during which genes are “shuffled” to/from a “paternal” chromosome to/from its
     “maternal” homolog; new combinations of genes produce slight different characteristics. You are special because
     during meiosis within your mother’s ovary, the best of your maternal grandmother’s genes were transferred to some
     of your maternal grandfather’s chromosomes, and those chromosomes luckily ended up in The ovum which was
     fertilized by The sperm whose chromosomes resulted from similarly fortuitous recombinations of your paternal
     grandparents’ genetic heritage.

    genetic variability or variation = relative genetic difference among sibling offspring; populations with low genetic
     variability are more vulnerable to new diseases, new predators, and other environmental changes. Sources of genetic
     variability are
                 recombination: [see above]
                 syngamy: if gametes are from different parents, they have at least a few differing alleles to combine in
              the zygote
                 mutation = DNA accidents which become new alleles
                 diploidy, which allows recessive [hidden] alleles to be passed to future generations, where they may be
              useful, without affecting the current generation, where the alleles could be disadvantageous if they were
              expressed and not hidden.
2. Living organisms have three main types of life cycles (diagrams available in Folder 5 and shown in lecture):
        a. primitive (haploid): all cells except the zygote are haploid; meiosis occurs in the zygote, producing daughter
        cells often called spores, which can divide by mitosis to begin new genetically unique haploid individuals.
        b. animal-like (diploid): all cells except the gametes are diploid; meiosis produces genetically unique gametes,
        which combine to produce the zygote, which begins a new genetically unique diploid individual when it
        multiplies by mitosis.
        c. alternation of generation: part of the life cycle is in the diploid stage; this part of the life cycle is called the
        sporophyte because some of its cells undergo meiosis to produce haploid daughter cells called spores. The
        genetically unique spores then each separately divide by mitosis to produce a haploid generation of individuals
        called gametophytes. Certain cells within each gametophyte differentiate to produce gametes. All the gametes
        from one gametophyte are genetically identical to each other. Two gametes, usually from different
        gametophytes, then undergo syngamy to produce the diploid zygote. The new sporophyte generation grows when
        each zygote divides by mitosis.
Fungi and most algae have some variation of the primitive haploid life cycle, but true plants always have the alternation
of generation type of life cycle. This life cycle is complex and involves too many parts and processes to be mastered
without unreasonable effort, which nevertheless you must exert to pass this course.


OPTIONAL FURTHER READING
http://www.huntington.org/BotanicalDiv/Timeline.html Plant trivia timeline
http://phylogeny.arizona.edu/tree/phylogeny.html Tree of Life Project




OPTIONAL PREVIEW / REVIEW QUESTIONS:

1. Can you draw the three general types of life cycles, showing these processes and structures in each one?
 meiosis, mitosis, syngamy, gamete, zygote
add these to "alternation of generation": spore, sporophyte, gametophyte

2. Can you show the ploidy of these cells? gamete, zygote, spore, sporophyte, gametophyte

3. Can you show the ploidy of the cells in this table?
         Cell ploidy before the process           Process      Cell poidy after the process
         Haploid (1n)                           Mitosis
         Diploid (2n)                           Mitosis
                                                Syngamy
                                                Meiosis

4.   How can a gene pool get more genetic variation?
B. FUNGAL BACKGROUND DETAILS.

1. Classification and characteristics of fungi. Fungi are spore-forming, heterotrophic eukaryotes, usually saprophytic
or parasitic. Many authorities group all fungi in the Kingdom Fungi, but some biologists lump the slime molds (see
below) and some small groups with the Protista. The specialists who study fungi are called mycologists. They
sometimes work in isolation from other biologists; this isolation helps explain why they use a vocabulary which seems a
little strange and in conflict with the terminology of other biologists. Amateur mycologists, who usually call themselves
foragers and call their field trips forays, often know far more about fungi than typical biologists know. Amateurs usually
eat some of the mushrooms they collect; professional biologists rarely trust their ID skills enough to risk their lives.
          a. The true fungi seem to be monophyletic [ = related to each other, sharing a common ancestor not related to
          similar forms whose resemblance resulted from convergence evolution.] The true fungi include the fleshy fungi
          (like mushrooms and puff balls and shelf fungi), yeasts, mycorrhizae (fungi which live symbiotically with plant
          roots), most molds, and many diseases of humans, other animals, and plants (including rusts, smuts, mildews,
          etc.).
                    All true fungi eat by absorbing food, usually after secreting digestive enzymes to hydrolyze and
                       dissolve whatever they are eating.
                    Their cell walls are made of chitin, a polysaccharide never found in plants but found in the shells of
                       insects, shrimp, crabs, etc. (Plant cell walls are cellulose.)
                    True fungi store their energy reserves as the polysaccharide glycogen, not starch, the polysaccharide
                       plants store.
                    A few fungi are unicellular, but most fungi form thread-like filaments called hyphae (one is a
                       hypha). Hyphae may be modified into root-like branched rhizoids and/or haustoria, which penetrate
                       the cells of a host. A bunch of hyphae compacted together may form a fleshy mass or body called a
                       mycelium.
                    True fungi have no specialized multicelluar tissues and no multicellular reproductive structures.
                    The true fungi are usually divided into three major groups, the zygomycetes, ascomycetes, and
                       basidiomycetes, each having distinctive reproductive structures you will study in lab, Atlas 24-31,
                       and on the next page.

        b. The slime molds are very much like ameba protozoans. Modern classification systems usually exclude them
        from the kingdom Fungi, but traditionally they have been grouped with other fungi because of their similar
        outward appearance, their similar natural habitats, and because they usually form sporangia and many spores,
        unlike typical protozoa.
                 Slime molds move like amebas. True fungi usually don’t move (except for the predatory worm-
                    trapping type); they just grow into the host or dead stuff.
                 Slime molds have no cell walls except around dormant spores or zygotes.
                 Slime molds eat by engulfing their food by phagocytosis before digesting it within an intracellular
                    vacuole which fuses with a lysosome. Most often they eat bacteria or yeasts or another fungus, which
                    was busy digesting something else.

        c. Lichens are a special category—true fungi with symbiotic algae living inside the mycelium, but not inside the
        actual cells of the fungus. These photosynthetic algae produce food for the fungus. In return, the fungus protects
        the alga from drying out and provides some fertilizer for the alga by absorbing compounds from soil or
        precipitation (even fog or even just air).
             Lichens with prokaryotic algae (see the algae lab) can fix nitrogen, using nitrogen gas instead of the
                nitrogen compounds other eukaryotes must compete for.
             The fungi in lichens usually cannot survive without their symbiotic algae. The algae can grow faster
                without the fungi under laboratory conditions; but in their natural habitats, these algae dry out or run out
                of mineral fertilizer and cannot survive alone.
             Lichens usually live in very harsh habitats where most other life forms cannot survive or during the “bad
                season” when their competitors cannot grow.
             The lichen equipment for absorbing minerals and water from thin air has a down side: they often
                accidentally absorb pollutants, which may eventually kill them. The good side of this problem is that
                lichens can be analyzed to evaluate air quality.
               More?    You want more? check out these links to lichen lore:
                        http://www.lichen.com/index.html
                        http://www.lichen.com/biology.html#anchor148955
                        LichenLand: http://mgd.nacse.org/hyperSQL/lichenland/index.html
                        LichenLand-Lite: http://mgd.nacse.org/hyperSQL/lichen_teach/

2. Reproduction. Almost all fungi produce vast quantities of spores, hard-coated cells which can survive unfavorable
conditions through dormancy. The spores are tiny; they can float along the slightest air currents to invade new habitats.
Most fungi reproduce both sexually and asexually. Life cycles in the fungi are extremely diverse, and some are very
unusual; but all the true fungi have variations of the primitive haploid life cycle (see Part A for review), where only the
zygote is diploid, and meiosis always occurs in the zygote.
        a. The most important life cycle to learn is the black bread mold Rhizopus, a zygomycete. You can learn a
        hand-out available in the lab and this description:
        Rhizopus is coenocytic [=the filaments are not separated into cells; each hypha is made of continuous cytoplasm
        with many haploid nuclei streaming through it.
                In its asexual phase, Rhizopus walls off the end of a special hypha to make a “sporangium” containing
                 regular haploid nuclei. You can see photos on
                 http://campus.queens.edu/faculty/jannr/Botany/images/slimies/fungi/rhizopusAsex%20copy.jpg. Each of these
                 nuclei forms a thin, but hard, coat and is called a spore even though it is not a true spore like the product
                 of meiosis in true plants. Each spore can start a new mycelium by mitosis. This process is analogous to
                 the clones produced by flowering plants except that the fungal cells are all haploid.
                In its sexual stage, you learn that different patches of Rhizopus may be different “mating types” [like
                 sexes only you can’t tell which is female]. To reproduce sexually,
                     two hyphae from different “mating types” (sometimes called "+" and "-") approach each other;
                     each hypha walls off its tip into a chamber [ = gametangium] containing many haploid nuclei.
                     These nuclei are now gametes.
                 The two gametangia fuse, labeled "[b]" at
                      http://campus.queens.edu/faculty/jannr/Botany/images/slimies/fungi/rhizopusZygospores%20copy.jpg.
                     Their gametes undergo syngamy to produce many diploid zygotes within the chamber, which has
                      now developed a heavy wall and is now called a zygospore (labeled "[c]" at
                      http://campus.queens.edu/faculty/jannr/Botany/images/slimies/fungi/rhizopusZygospores%20copy.jpg ).
                     Later, the zygotes will undergo meiosis to produce many, many true haploid spores. As meiosis
                      occurs, the zygospore re-arranges itself into a sporangium with a long stalk. When the sporangium
                      opens, each haploid spore can start a new mycelium by mitosis.

        b. The basidiomycetes and ascomycetes are more common. Their typical life cycle is described here and is
        also outlined on a lab hand-out. You need to learn it too. These fungi, like most true fungi, are septate [=have
        walls dividing the hyphae into cells, not coenocytic].
                 The sexual phases of their life cycles are similar to the Rhizopus life cycle except that syngamy is
                    divided into two events, separated by some other strange situations: plasmogamy [ =“cytoplasm-
                    marriage”] precedes karyogamy [ = “nucleus-marriage”]. In plasmogamy, which typically happens
                    underground or within the host, two gametes fuse completely except for their nuclei. The resulting
                    cell is dikaryotic, having two haploid nuclei [= n + n ]. The two nuclei synchronize their mitotic
                    divisions repeatedly to produce an extensive dikaryotic hypha which wraps about itself to produce a
                    fleshy dikaryotic mycelium which rises above the ground or rotting host, eventually forming a
                    fruiting body, which is a mushroom or a shelf fungus or something else more fleshy than moldy in
                    texture. The fruiting bodies are sometimes called ascocarps and basidiocarps. Within the dikaryotic
                    fruiting body only a few cells undergo karyogamy to produce some diploid zygotes. The zygotes
                    then divide by meiosis to produce haploid spores. The spores leave the fruiting body and then
                    eventually may germinate and divide by mitosis to form a new haploid mycelium.
                          In basidiomycetes or "club fungi" (mushrooms, for example), karyogamy occurs within
                             stumpy club-shaped cells called basidia. The zygote formed within each basidium then
                             divides by meiosis to produce four spores, called basidiospores. They are transported to the
                             outside of the basidium, usually at the edge of a structure like the gills under a typical
                              mushroom cap:
                              (http:// campus.queens.edu/faculty/jannr/Botany/images/slimies/fungi/basidiospores40xn2%20copy.jpg)
                              The Only Way to tell that a fungus is a basidiomycete is to use a microscope to confirm the
                              presence of rows of distinctive basidia, each with four basidiospores.
                          In ascomycetes or "sac fungi" (cup fungi, for example), karyogamy occurs within longer,
                              sac-shaped cells called asci. The zygote formed within each ascus then divides by mitosis to
                              produce four haploid cells, each of which divides again by mitosis, so that the mature ascus
                              contains eight ascospores. Again, positive identification of a suspected ascomycete is
                              finding the distinctive rows of asci, each looking like a little sock containing eight spores in
                              a row
                              (http:// campus.queens.edu/faculty/jannr/Botany/images/slimies/fungi/Ascospores40x%20copy.jpg ).
                   Most moldy ascomycetes also have an asexual stage in which they form stalks called conidia, which
                    in turn bud off asexual (cloned) spores called conidiospores. The length and branching pattern of
                    the conidium and its conidiospores helps mycologists identify a mold’s genus and species.
                   The Fungi Imperfecti =Deuteromycetes = Deuteromycota are molds which have no known sexual
                    stages, but zillions of conidiospores.
                    (http:// campus.queens.edu/faculty/jannr/Botany/images/slimies/fungi/penicillium2%20copy.jpg )
                    Most mycologists believe that the imperfect fungi are ascomycetes which have mutated, losing the
                    ability to form gametangia. However, every now and then somebody finds one reproducing sexually,
                    and then it gets re-classified. Mycologists found one imperfect fungus which just looked so different
                    from its sexual stage that the two stages had been classified as two different species. Several
                    mycologists have made this mistake with several different Ascomycetes.
                   Textbooks may picture other structures, like fancy gametangia or extra terminology for many
                    ascomycota (ignore additional terminology in any source) and more stages or more types of
                    infectious spores for many diseases (ignore details when studying for test 2), but the information
                    described above is all you need unless you decide to mutate into a mycologist or a pathologist or a
                    plant pathologist. If you really want to learn more, here's a good place to start:
                    http://phylogeny.arizona.edu/tree/eukaryotes/fungi/fungi.html

        c. Slime molds, water molds, and some other fungi have life cycles very different from these described here.
        This course omits them.

3. Why do botanists care about fungi?
      a. Fungi cause diseases of plants and botanists and their pets and loved ones. (Optional gross stuff at
        http://www2.provlab.ab.ca/bugs/webbug/mycology/dermclin.htm )
        b. Fungi change habitats by decomposing wastes and corpses and then recycling the minerals for plant uptake.
        They condition the texture, organic “humus” content, particle size, pH, and water-retention capacity of soils.
        The lichens often are pioneers in primary natural succession, paving the way (or better, plowing or even creating
        the soil), so that true plants can eventually colonize a habitat. The mycorrhizae are so critical to some plant
        symbionts that their seeds don’t even bother to germinate unless the mycorrhizal hyphae have already colonized
        the plant’s integuments.
        c. Fleshy fungi provide food for botanists, other animals, and even other fungi which colonize a mushroom, for
        example.
        d. They help botanists preserve grains (as fermented beverages) and milk (as cheese and yogurt, sometimes with
            the help of bacteria). Some botanists use them to produce leavened bread without resorting to chemical
            additives like baking powder. The subtle varieties of flavors of various beverages, breads, and cheeses may
            deter botanists from seeking variety in other avenues of personal experience.
                                                                                              more reasons on next page
        e. Some of the fungi make botanists healthier by out-competing other microbes attempting to colonize our
        bodies; some botanists who own stock in pharmaceutical corporations also become wealthier when the
        corporations sell fungal extracts as antibiotics, etc. Other botanists become wise by applying their knowledge of
        fungi to other areas of scholarship.
        f. Here's a standard textbook answer to the question (useful for review):
        http://www.hcs.ohio-state.edu/hcs300/fungi.htm
        g. Most of the really important stuff: http://phylogeny.arizona.edu/tree/eukaryotes/fungi/fungi.html


(OPTIONAL) CHECKLISTS for before or after lab
1. Are fungi
        a. prokaryotic or eukaryotic?
        b. autotrophic or heterotrophic?
        c. unicellular or multicellular?
        d. plants or animals?
2. Compare and contrast
        a. hypha/mycelium/fruiting body (ascocarp or basidiocarp)/rhizoid
        b. chitin /cellulose
        c. starch/glycogen
        d. mitosis/meiosis
        e. gametangium/sporangium
        f. syngamy/karyogamy/plasmogamy
        g. haploid/diploid/dikaryotic
        h. zygote/spore/zygospore/conidia
3. Define (OPTIONAL)
        myco-             gam-           angi-          a-      karyo-    asco- basidio-

4. SAMPLE QUIZ
[a] Spore-forming, heterotrophic eukaryotes are traditionally classified in the kingdom ___________.
[b] Slime molds and water molds are now often classified in the kingdom __________________.
[c] Most bread molds and cheese molds are usually classified in the kingdom __________________.
[d] Lichens are classified as fungi, but actually they are both ___________ and _______________.
[e] Are slime molds closely related to other fungi? How do we know?
[f] Fungi were once believed to be related to plants; what evidence disputes this hypothesis?
[g] How do bread molds differ from slime molds in feeding?http://campus.queens.edu/faculty/jannr/botany/slimies - fungi
[h] How are they alike in feeding method?
[i] What would happen to a forest if there were no saprophytes?
[j] How do fungi manage to get inside refrigerators, etc.?
[k] Why do many fungi seem to grow in rings?
[l] Lichens are THE classic example of a relationship called ____________; what do the fungi and algae gain and
contribute in the relationship?
[m] In what way are lichens similar to mycorrhizae? What are "V-A" or endo-mycorrhizae?
[n] What's a truffle, and why are truffles expensive?

check answers on the survey web page: http://campus.queens.edu/faculty/jannr/Botany/slimies.htm#Fungi
FUNGUS VIDEO to be shown in lab Wednesday
1. The video is about fungi: molds, mushrooms, yeasts, etc. Notice that the British narrator pronounces them "fun-
ggee," but most American botanists say, "fun-jiiii." Near the beginning, the narrator refers to the "beauty or beast"
aspects of fungi, and throughout the video he keeps mentioning positive and negative aspects of fungi. You might want to keep
a list like this:
beautiful:
beastly:

2. Who were the medieval herbalists, and why did fungi matter to them?

3. What characteristics of fungi make them seem to be associated with supernatural effects, magic, and     could it be   the devil?

4. What is a "fairy ring"?
What other rings are caused by similar effects?


5. How does a mycelium digest its surroundings?
How is this related to decay and decomposition and ecological mineral cycles?



6. What is a spore?

7. What is the job of a mushroom (the above-ground parts)?

8. Why do cup fungi have cups? What is their job?

9. What is the dust that is blown out of mushrooms, cup fungi, bird's nest fungi, etc.?
Why is there so much dust?

10. Why does he keep referring to the 3rd kingdom?
How many kingdoms are there anyway?

11. Examples of interactions with insects, list some:

12. Interactions with algae (the Lichens!), describe or explain:

13. Examples of interactions with us and our stuff:

14. Why would a fungus lasso a worm?

15. Smuts, rusts, blights, mildews: what do they have in common?

16. Irish potato famine: What's its connection to water, fungi, American history?

17. Slime molds considered by some authorities to be protozoa (protist animals), not fungi. What characteristics of slime
molds are animal-like? Which slimy characteristics are fungal?

18. In summary, how are fungi like the beauty?


And how are they like the beast?
LAB ACTIVITIES
1. Learn to identify slides of the following groups (divisions or phyla in some classification systems; classes in other
   systems) of fungi. The best way is the distinctive reproductive structures; this is easier if you have already learned their life
   cycles:

    a.       Zygomycota or zygomycetes have distinctive gametangia (=gamete-containers), sporangia (=spore-containers),
             and zygospores (in this case a zygospore is the distinctive container where zygotes apparently undergo meiosis to
             produce spores, but sometimes it means something else in other groups). You must remember that Rhizopus, the black bread mold, is in
             this group. Pronunciation: RIZE-oh-pus in ZIE-go-my-COT-uh or ZIE-go-my-SEE-tease.
             Study these two types of slides of Rhizopus [=black bread mold]




                          "sporangia"                                             Zygospores:This slide shows the sexual phase,
This is the vegetative or asexual phase of the life cycle.                        and it is one of THE classics required in botany classes
All these structures are haploid. Locate and identify                             everywhere. You are expected to remember that all the
functions for each of the following:                                              structures except the zygotes are haploid. Locate and
 a hypha (HI-fuh) is a strand within the mycelium (labeled                       identify functions for each of the following:
     [e] on the zygospore slide at right).                                         hypha ([a] and [e])
 [a] rhizoid (RYE-zoyd), a hypha specialized for anchoring the sporangium         rhizoids may be on your slide
     stalk
                                                                                   gametangium (GAM-ee-TAN-jee-um), [b]
 [b] "sporangium," and the black or brown “spores”                                (and then in more mature stages where the gametangia have fused)
  arranged like an "afro" type haircut. (Picky botanists reserve                      zygospore [c] (which may contain zygotes until meiosis
     the terms “spore” for cells produced by meiosis; the so-called "spores" of
     Rhizopus are asuxual spores, like conidiospores of Ascomycetes and               occurs),
     Deuteromycetes below—part “c”); so the so-called sporangia and spores on      and then (in even more mature stages) you may find
     this slide are NOT true botanical spores and sporangia.)
                                                                                      new haploid filaments “hatching” out of much older
                                                                                      zygospore. You may also find on the zygospore slide the asexual
                                                                                      “spores” and "sporangia" like you saw on the first slide.

            See more links and info in the background information and at
             http:// campus.queens.edu/faculty/jannr/Botany/slimies.htm#Fungi ,
   b. Ascomycota (after formation of a zygote) produce 8 spores within a sac-shaped ascus. Yeasts, many molds, and
      a few fleshy fungi are in this division. Look at a slide of Peziza (pea-ZIE-zuh), a cup fungus. On future events, you
      must be able to recognize this slide as an example of the fruiting body of Ascomycota or Ascomycetes, and you
      might be asked which cells are haploid (the ascospores), which cells are diploid (only the zygote, which is not on these
      slides because they were made after meiosis occurred), and which cells are dikaryotic (all the others shown here).
         Ask-us about pronunciation of ASK- oh-my-COT-uh. and ASK-us and ASK-oh-my-SEE-tease.




[a] is the space inside the "cup" of Peziza                                  This is a close-up of some of the asci.
[b] is the row of asci with ascospores inside, almost ready                  Each ascus originally contained a single diploid zygote
to be released into the cup                                                  produced by karyogamy.
[c] is the dikaryotic mycelium beneath the asci. The cells                   Then the zygote divided by meiosis into four haploid
in these hyphae are all dikaryotic, produced by mitosis                      spores. Then each spore divided by mitosis so that each
from the original cell created in plasmogamy. These cells                    ascus contains eight haploid ascospores.
will never get to undergo karyogamy.



   c.   The asexual conidia are indicative of either Ascomycota
        or Deuteromycota. but the Deuteromycota never
        produce the ascus because they are always virgins. This
        is why Deuteromycota are sometimes called Fungi
        Imperfecti; explain why mycologists would even think or a name
        like this. Although molds can be in any fungal division,
        the most common molds are either Ascomycota or
        Deuteromycota. Some molds are classified in both
        groups after the species is discovered not to be nonsexual
        after all. Look at a slide of Penicillium. Note the
        “chicken-finger” appearance of the chains of conidia.
        On future events, you must be able to identify this slide
        as demonstrating conidia, the characteristic asexual
        spores of either Asco- or Deuteromycota. (cone-ID-ee-uh are
        abundant in the DUTY-row-my-COT-uh. = DUTY-row-my-SEE-tease, a.k.a
        FUNJ-I im-purr-FECKT-I, unless you’re British, who say FUN-GKEE im-purr-
        FECK-TEE)

   See more links and info in the background information and at
   http:// campus.queens.edu/faculty/jannr/Botany/slimies.htm#Fungi
    d. Basidiomycota (after formation of zygotes) produce 4 spores attached to the end of a club-shaped basidium, ***.
        Know the basic microscopic parts of a mushroom (***)(Coprinus is the genus in our slides): cap with gills
       containing basidia at the edges, and the 4 basidiospores [all of these are parts of the fruiting body or
       above-ground mycelium or basidiocarp]. (koe-PRINE-us is a JEAN-us which has buh-SID-ee-uh on its gills. It has a die-care-ee-OTT-ick
        my-SEAL-ee-um.)




[a] is the edge of the mushroom cap                                       This closer view of the basidiospores hints that they are
[b] is a gill, or thin flap of mycelium, usually on the                   "pushed out" of the stubby basidium as they form from the
underside of the cap.                                                     diploid zygote. Meiosis does produce four basidiospores,
[c] are the basidiospores lining the gills                                but the slide-makers nearly always knock off most of them
[d] is the stalk (in x-sec)                                               during their slicing and dicing. Remember that a
                                                                          mushroom is dikaryotic except for the basidiospores and
See more links in the background information and at                       zygote which produced the basidiospores.
http://campus.queens.edu/faculty/jannr/Botany/slimies.htm#Fungi

2. Examine as many fungal specimens as possible. Learn to identify gross specimens as belonging to one of the following
groups:
    a. Molds: it’s enough on practical sections just to say that a very gross gross specimen is a mold, probably a fungus
        but maybe a slime mold. See if you can pick out the slime molds. (Could be bonus points on a test.) True
        MOLDS may be in any division of the Kingdom Fungi. You need a microscope to tell which division. The
        plastic mount of Penicillium shows the concentric rings found in many fungal growths, and you may be able to
        see the rings on some slides in #1. Slime molds and water molds are usually classified as divisions within the
        Kingdom Protista. Again, you cannot tell which division (and often not even which kingdom) without a
        microscope. You are expected to be able to explain some reasons for their classification, but you do not have to discuss their orgies or
        other sexual aspects of slime molds. You do need to know the details of the life cycles of the Zygo-, Asco-, and Basidiomycota.
    b. Diseases are sometimes molds and sometimes dikaryotic fruiting bodies. Look at some of them.
    c. Fleshy Fungi (mushrooms, shelf fungi, etc.) are the dikaryotic fruiting bodies of either Ascomycota or
        Basidiomycota. You don’t need to be able to tell which division, except on the microscope slides. But
        professional mycologists do know which are which, and you could figure it out using a mushroom manual. Know
        the basic gross (and microscopic) parts of a mushroom: stalk, cap with gills or pores containing spores [all of
        these are parts of the fruiting body or above-ground mycelium or basidiocarp (see pictures next page) or
        ascocarp]. The underground mycelium is huge but invisible; be able to explain.
    d. Lichens are usually (but not always) Ascomycota with distinctive asci and also with algal (sometimes cyanobacterial)
        symbionts (see Physcia slides or next page pictures). Some classification systems have a separate division for
        lichens. For you, it’s enough to be able to identify a gross specimen as a lichen. The best preparation is to look
        at lots of pictures and specimens so that you develop a liking for them.
For all of these, you also need to sound smart when you’re asked about their importance in ecology, medicine, etc. Read
the textbook, and look at the pictures and videos and website movies!
                                                                   On the slide of the
                                                                   lichen Physcia at left,
                                                                   [a] is the row of asci
                                                                   [b] is a patch of algae
                                                                   [c] are other parts of
                                                                   the fungal mycelium
                                                                   (dikaryotic).

                                                                   A slide of a puffball,
                                                                   Lycoperdon, top right,
                                                                   shows that it is packed
                                                                   with spores.

                                                                   The familiar
                                                                   mushroom, bottom
                                                                   right, is technically
                                                                   called a basidiocarp.
                                                                   Point out the stalk,
                                                                   cap, and gills.




3. Look at some of the manuals and keys for lichens and fungi. Are the keys all dichotomous, like RAB? Becoming an
expert at identifying fungi is not easy, but you could train yourself with a few books from a library or used book store.
Amateur mushroom foragers are found everywhere.
 A simple key to lichens http://www.mykoweb.com/CAF/skey.html
 More keys and information linked at http:// campus.queens.edu/faculty/jannr/Botany/slimies.htm#Fungi

4. Several videos and folders are available for your convenience and fun. And much more information is available at
http:// campus.queens.edu/faculty/jannr/Botany/slimies.htm#Fungi

				
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