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Figure 1. Fungal forms of either singles cells or hyphae (filaments)
Kingdom Fungi
Molds, Sac Fungi, Mushrooms, and Lichens
Essential Question(s): What makes fungi have their own kingdom?
Objectives:
1. Student will be able to describe the characteristic features in the kingdom Fungi.
2. Student will be able to compare and contrast the fungi with plants and animals in terms of
body plan and life cycle.
3. Student will recognize and discuss various forms of fungi and their respective reproductive
cycles.
Fungi are a diverse group of organisms that have two major roles; decomposition of organic materials
and to symbiotically aid algae and plants. Examine the chart below showing basic characteristics of
fungi.
Cell
Feature
Eukaryotic, no chloroplast present, cell wall made of chitin
Body Plan Multicellular (hyphae) or Unicellular
Nutrition Heterotrophs by extracellular digestion followed by absorption.
Life Cycle Haploid (multicellular) and diploid (unicellular) phase
Introduction:
Fungi are not photosynthetic
and therefore cannot produce
their own food like plants do.
Much like animals, fungi are
heterotrophs. However fungi
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Figure 2: Chytridiomycota, Zygomycota, Basidiomycota, and
Ascomycota are the four major phyla in the Fungi Kingdom
Figure 3. General life cycle of fungi.
are absorptive meaning they do not ingest their foods are first extracellularly digested and then
absorbed. Fungi are saprophytes meaning they feed on dead or decaying organic matter.
The hyphae (thread‐like structures), are the most
basic structure of fungi and contain many nuclei
distributed throughout the cytoplasm.
Sometimes the hyphae are divided into
compartments by cross walls called septa. Fungi
with cross walls are called septate fungi, while
fungi without cross walls are called coenocytic
fungi. A collection of hyphae is called
mycellium. The mycellium can penetrate water,
soil, and living tissue in order to absorb
nutrients through the tips of the hyphae that
produce digestive enzymes to digest organic
material. The soluble products are absorbed into
the hyphae. There are four major phyla, Ascomycota, Basidiomycota, Zygomycota, and
Chytridiomycota. Classification of fungi is determined based on differences of specialized structures
during their reproductive cycles. Fungi reproduce asexually most often but they do have a sexual
reproductive phase.
Asexual Reproduction:
Asexual reproduction occurs through mitosis of
haploid cells in three different methods. Spores
are produced in reproductive structures called
sporangia, and conidiophores, among others.
Spores are well equipped to endure harsh
environments and when optimal conditions
arise, they have the ability to develop into a
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fully functional organism. During budding, another method of asexual reproduction, a cell arises
and grows from the original cell and then detaches itself and develops into a new organism. In yeast,
budding usually occurs in the uneven distribution of the cytoplasm through mitosis. Fragmentation
is the breakage of an organism into one or more units that can individually give rise to new
mycelium.
Sexual Reproduction:
Sexual reproduction of fungi begins when hyphae from two genetically different individuals meet.
Once the hyphae meet the two haploid cells will often fuse their cytoplasms in a process called
plasmogamy having two nuclei per cell (dikaryotic). Karyogamy is the fusion of the two nuclei to
become diploid zygotes. The generalized life cycle of a fungus has four important features: 1) during
most of its life cycle the nuclei in mycelium are in the haploid state. 2) Mitosis occurs to produce
gametes during which haploid cells are differentiated. 3) Soon after formation of the zygote (diploid),
meiosis takes place. 4) Meiosis produces more haploid cells called spores. Spores are not gametes but
rather haploid cells that develop into a haploid organism through mitosis.
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Phylum Illustration Common name Reproductive Characteristic
Chytridiomycota
Chytrids
Zygomycota
Zygote Fungi
Ascomycota
Sac Fungi
Basidiomycota
Club Fungi
Figure 4: Summary table of four fungi phyla, their general appearance, and reproductive structures.
Chytridiomycota:
These are the group of fungi known as the chytrids, whose distinctive characteristic is their
flagellated gametes. Chytrids have a well‐defined sporophyte diploid stage. They are responsible for
a significant reduction on the populations of many amphibians.
Slides
1) Obtain 2 common chytrids : Allomyces or Chytridium and prepare a wet mount to examine
morphology.
a) Draw your observations from the wet mounts.
b) Are hyphae apparent?
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Figure 5. Reproductive structures of Rhizopus (bread mold); Rhizopus reproductive structures.
Zygomycota:
Zygomycetes are most commonly known as the bread molds. They are characterized by their sexual
structure called the zygosporangium, the short diploid stage. The vegetative hyphae lack septae
versus the reproductive structures which are septate. The most common genus of the bread mold is
Rhizopus. Refer to these figures below to become familiar with sexual and asexual reproduction of
zygomycetes.
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Figure 6: Life cycle of Rhizopus, bread mold)
Observe:
1) Obtain a petri plate with moldy bread that has been moistened and exposed to air from
your instructor
2) Use dissecting microscope to examine mycelia, note if they are tangled.
a) Describe the texture and the color of the molds. Where is the pigment concentrated on each mold?
b) How many species of molds do you have?
c) Why is it significant that bread molds have meiosis (as in plants) to produce spores and asexual
spores produced my mitosis?
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Figure 8: Penicillium Conidia 100x
Figure 7: Rhizopus Conjugation 40X:
Lactophenol alcohol cotton blue
Figure 9: Yeast, Saccharomyces
3) Observe prepared slide of Rhizopus
conjugation and Rhizopus Sporangia under a
microscope.
Ascomycota:
Ascomycetes (sac fungi) have a sac shaped reproductive
structure called the ascus. Acomycetes are a diverse group
that includes yeasts, truffles, morels, and some molds. Some species like Penicillium lack the sexual
stage. Asexual reproduction takes place by the formation of conidia, specialized spores. Each
conidium may contain one or more nuclei. In ascomycetes conidia form on the surface of the
conidiophore unlike the spores of Rhizopus which form within the sporangia. Yeasts are a type of
ascomycete whose bodies are not made from hyphae and are unicellular. They have both sexual and
asexual reproductive cycles but the most prevalent cycle is asexual reproduction by mitosis.
Slide:
1) Using a microscope to observe Penicillium Conidiophores prepared slide,Penicillium Conidia 100X.
2) Obtain a stock culture of Saccharomyces (yeast) and prepare a wet mount by using only a small
amount.
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a. Describe the morphology of yeast cells.
b. Compare the yeast hyphae to that of mold hyphae.
3) Obtain a culture plate of living Aspergillus, Penicillium, or Neurospora and examine the soft
texture of the colonies under a dissecting microscope.
Basidiomycota:
Figure 10. Basidium schematic
Basidiomycetes are the most familiar fungi that include puff balls, shelf fungi, and mushrooms. This
group is characterized by its reproductive structure called the basidiocarp, a tight bundle of hyphae.
The basidiocarp forms a cap and gills.
Observe:
1) Examine fresh mushrooms (earthstar). Using a
scalpel obtain a thin slice and observe under a microscope to
look for spores on the gills of the mushroom.
a. Where would you find dikaryotic cells, haploid cells, and
Figure: 11 Coprinus Mushroom
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Figure 9: Lichen Thallus 100X
diploid cells?
2) Observe the prepared slide Coprinus Mushroom under a microscope to observe the spores
and hyphae.
Lichens
A lichen consists of two organisms living together in a symbiotic relationship. In most cases the two
organisms are fungi (ascomycete) with a photosynthetic algae (protist) or cyanobacterium. The algae
provides the sugars produced by photosynthesis while the fungus provides protection and nutrients
used by the alga. This symbiotic relationship allows both organisms to proliferate in harsh
environments.
1) Observe the prepared slide of lichen thallus
a. Draw your observation labeling the algal cells and
fungal cells.
2) Observe the whole lichen.
a. Where would you expect to see lichens. Why?
Figure: 12 Lichen Thallus
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Sources:
1. Content Survey of the Fungi Kingdom: Molds, Sac Fungi, Mushrooms, and Lichens
2. De Anza Lab Manual http://faculty.deanza.edu/heyerbruce/bio6a
Image Sources:
Figure 1 ‐ Fungal forms http://gallery4share.com/s/saccharomyces.html,
https://www.google.com/search?q=fungal+forms&rlz=1C1KMZB_enUS545US545&espv=2&biw=1440&bih=799
&source=lnms&tbm=isch&sa=X&ved=0CAYQ_AUoAWoVChMIj5S2k5H6xgIVyJENCh0L0wKZ#tbm=isch&q=
hyphae+filaments&imgrc=h‐5VSlO1nAQcFM%3A
Figure 2 ‐ Four major fungi phyla
http://faculty.collegeprep.org/~bernie/sciproject/project/Kingdoms/Fungi5/Fungi_Evolution.htm
Figure 3 ‐ General Life cycle of fungi http://www.tanelorn.us/data/mycology/myc_life.htm
Figure 4‐ Summary table of fungi:
http://www.apsnet.org/edcenter/intropp/PathogenGroups/Pages/Oomycetes.aspx
ʺSpizellomyceteʺ by Author and original uploader was MidgleyDJ at en.wikipedia ‐ Transferred
from en.wikipedia to Commons.. Licensed under CC BY‐SA 2.5 via Wikimedia Commons ‐
https://commons.wikimedia.org/wiki/File:Spizellomycete.jpg#/media/File:Spizellomycete.jpg
https://sharon‐taxonomy2010‐p2.wikispaces.com/Fungi
ʺSmardz‐Morchella‐Ejdzej‐2006ʺ. Licensed under CC BY‐SA 3.0 via Wikimedia Commons ‐
https://commons.wikimedia.org/wiki/File:Smardz‐Morchella‐Ejdzej‐2006.jpg#/media/File:Smardz‐Morchella‐
Ejdzej‐2006.jpg
ʺAscocarp2ʺ by Debivort. Licensed under CC BY‐SA 3.0 via Wikimedia Commons ‐
https://commons.wikimedia.org/wiki/File:Ascocarp2.png#/media/File:Ascocarp2.png
https://commons.wikimedia.org/wiki/File:Amanita_muscaria_(fly_agaric).JPG
https://www.studyblue.com/notes/note/n/bio‐211‐study‐guide‐2014‐15‐dr‐john‐fowler/deck/12725408
Figure 5 ‐ Bread Mold http://www.biologyjunction.com/fungi_notes_b1.htm
Figure 6 ‐ Bread Mold life cycle
https://www.google.com/search?q=chytrids+public+domain&biw=977&bih=771&source=lnms&tbm=isch&sa=
X&ei=OMyRVajiOsbcQH6x4CoDA&ved=0CAYQ_AUoAQ#tbm=isch&q=rizopus+reproductive+cycle+public+
domain&imgrc=n3aOebOsfa_eDM%3A
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Figure 10 ʺBasidium schematicʺ by Debivort ‐ From English Wikipedia. Licensed under CC BY‐SA 3.0 via
Wikimedia Commons
https://commons.wikimedia.org/wiki/File:Basidium_schematic.svg#/media/File:Basidium_schematic.svg