Updated: Tuesday, July 6, 2010
Eukaryotic
Microbes
Supplemental instruction
Fall 2010
For Dr. Wright’s Bio 7/27 Class
Picture from http://berkeley.edu/news/media/releases/2006/12/21_microbes.shtml http://sustainabledesignupdate.com/?p=409
http://www.mycology.adelaide.edu.au/gallery/hyaline_moulds/?template=print
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Eukaryotic microbes: Eukaryotic microbes: we considered unique features of each, their niche in the environment,
and whether they might cause disease.
Algae: as photosynthetic organisms, why are they so important in the environment? What features of algae
are considered when classifying them? What are some potentially harmful effects of algae?
Fungi: what features of fungi make them so unique that they are grouped in their own kingdom? How do
fungi reproduce? Fungi are placed into groups according to what feature? What is the major
contribution of fungi to ecosystems? What are some differences between yeasts and molds? What is
a dimorphic organism? What are some potentially harmful effects of fungi? How can fungi cause
disease?
Protozoa: In what kingdom are protozoans found? What is the distinguishing feature of Mastigophora,
Sarcodina, Ciliophora, Apicomplexa? How do they reproduce? Why is their complex life cycle a
challenge in treating (or preventing) disease caused by protozoans?
What is a parasite? What is a saprophyte? Which type of the above organisms can be parasitic? Which
types can be saprophytes?
Helminths: what are the three major types of worms that we discussed in class? Be able to give examples of
each, the disease they cause, and explain how they are transmitted to the host?
What do we mean by primary and secondary host? Which is which?
Vector: what is the difference between a mechanical vector and a biological vector? Give examples of each.
What do we mean by “vector control” and how is it achieved? Why might this help reduce the spread
of certain diseases?
-From Study guide Dr. Wright Bio27 Fall 2009
Symbiosis - living together; love each other
http://plantbio.berkeley.edu/~bruns/tour/fungi2.html
; can be single love.; one side hates the other.
1) Mutalism (both beneficial) love each other.
mycorrhizae = fungi +plant roots
• ___________
fungi~ nitrogen fixation
plant~ provide sugars
•Lichen = ____________
Algae or cyanobacteria+fungi
algae or cyanobacteria – provide sugars
fungi – provide by retaining water
*Cellulose –undigestible carbohydrate.
•Cellulose-digesting symbiosis
Herbivores + bacteria
_________________
or protozoans
Help to digest cellulose
• Bacteria in the large intestine
Help to digest Vitamin K and B.
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1) Commensalism (one beneficial; no harmful)
Single love
Bacteria living on the skin to get food and others.
the host (human) – to get nothing; no harmful
one side hates the
2) Parasitism (one beneficial; the other harmful) other.
Parasites
bacteria, protozoa, algae, fungi, and helminths that cause disease
http://www.polconsultant.com/conteduc/immunolog
y/invaders.htm
http://www.ctahr.hawaii.edu/nelsons/kava/algae2.jpg
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Saprophytes
-any organism living upon dead or
decaying organic matter.
-obtain nutrients from dead organic
matter.
-Most fungi in eukaryotes
some bacteria in prokaryiotes
Mycobateria
What is the difference saprophytes from decomposers?
___________
Saprophytes are organisms that live and feed on dead
organic matter.
-Most fungi and some bacteria.
___________
Decomposers are organisms that breakdown complex
organic (dead or decaying organisms) into simpler mineral
components.
-Fungi, bacteria, and protozoa.
Picture from http://en.wikipedia.org/wiki/Saprotroph
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Protozoa (Kingdom protista)
-Only unicellular
-Not photosynthetic but, Euglena?
-Sexual ~fusion of gametes, conjugation..
Asexual ~ binary fission or multiple fissions
-Motile(flagellates, cilia)
-Lack cell wall
-some are decomposers
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Protozoa (cont’d)
•Classified by…
- mean of movement: cilia, flagella, peudopodia or nonmotile
Mastigophora, Sarcodina, Ciliophora, Apicomplexa
-Sarcomastigophora (Mastigophora)
by flagella; pathogen
-Ciliophora
by cilia; free-living
-Apicomplexa
by pseudopodia; parasitize other hosts
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Protozoa (Kingdom protista)
•Reproduction
- polymorphic
trophozoite
___________
~ Vegetative or feeding form
Favorable environment
cyst
___________
~ Resting form, also can reproduce
Adverse conditions
Protective cyst wall within the cytoplasm.
Lack of nutrient, moisture or oxygen, toxic..
For dispersal and survival.
- Sexual
syngamy- gametes from different individuals.
autogamy- gametes are formed and then fuse.
Conjugation
- Asexual
~ Binary fission; Budding; Schizogony (multiple fission)
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Algae (Kingdom protista)
-uni- or multicellular
-Photosynthetic
(chlorophylls and other photosynthetic
pigments)
-sexual ~ conjugation, fusion of Gametes,…
asexual ~ binary fission.
-No vascular system
-Some motile
-Rigid Cell wall
;cellulose a/w pectin; silica(diatoms)
•Environmental
-Photosynthetic; produce O2
-Primary producer: food source
-Most live in fresh or salt water
but, live nearly everywhere.
-Lichen (symbiosis: Mutualism)
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Algae (Con’td)
•Potential harm
-”Bloom”; red tide by
dinoflagellates
- Toxin
shellfish poisoning
*Caution in the Lab - AIDS.
•Classified by…
- photosynthetic pigments (chlorophyll a, b, carotenes…)
Brown algae, green algae, red algae
- storage molecules (starch, fats, oils)
- habitat: fresh or salt water
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Euglena?
-Kingdom protista
-Photosynthetic
-eye spot
-motile: flagella
-Alage? Protozoa?  Controversial!
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Fungi(Kingdom fungi)
-uni-(yeast) or multicellular
-NOT photosynthetic: “saprophytes
-Sexual ~ zygospore, asci, basidiospores
Asexual ~ budding, binary fission
-Dimorphic
-Non-motile
-Cell wall: Chitin
-some decomposers,
some saprophytes
some parasites
-Food production: bread, cheese
Infectious athletes foot!
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Helminths(Kingdom animalia)
-multicellular
-Sexual
-nematodes (roundworms)
trematodes (flukes)
cestodes (tapeworms)
-parasites
Arthropods (Kingdom animalia)
-multicellular
-Sexual
-insects, ticks, fleas, lice, mites
-some parasites
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cyst
trophozoite
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Fungi(Kingdom fungi)
-uni- or multicellular
-NOT photosynthetic: “saprophytes
-Sexual ~ zygospore, asci, basidiospores
Asexual ~ budding, binary fission
-Dimorphic (mold or yeast form)
-Non-motile
-Cell wall: Chitin
-Antibiotics, Vaccines
•Classified by…
-means of sexual reproduction.
Zygomycetes ~ Zygospores
Basidomycetes ~ Basidiospores
Ascomycota ~ Ascus
Deuteromycetes ~ budding, absent or unknown.
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___________Dimorphic
can exist as mold/hyphal/filamentous form or as
yeast.
Fungi grow …
as mycelia(mold) in soil or spores in the air.
as yeast-like cells in the body.
•Yeast
- single-celled
- Asexual
•Mold
- Multicellular
- Hypae (collectively mycellium)
binary fission or budding
*Yeast infection
*Food spoilage
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___________
Dimorphic
- can exist as mold/hyphal/filamentous form or as yeast.
in fungi
Spores in the air are inhaled
 develop into yeast-form in the lungs
 disease
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Helminths(Kingdom animalia)
-multicellular
-nematodes (roundworms)
trematodes (flukes)
cestodes (tapeworms)
-Sexual
-Parasites
•Cause disease through…
-Primary/secondary host
-Ingesting infected food (beef, pork..)
-Swimming infected water (penetrating skin).
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Arthropods (Kingdom animalia)
-multicellular
-sexual
-insects, ticks, fleas, lice, mites
-allergens
-carry cysts of protozoa
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______
Vector - transmit microorganisms or viruses to human.
•_________
Mechanical vector
-transfer contaminated food
from one location to other.
- Flies
Biological vector
•_________
- act as a host for a pathogen before
it is transmited to another organism.
- Mosquitoes
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_________
Host
:an organism that harbors a virus or parasite, or a mutual or
commensal symbiont, typically providing nourishment and
shelter.
_______________
Primary host
-a host in which the parasite reaches maturity
-reproduces sexually. trophozoite
-usually human, big animals but not always.
________________
Secondary host
-host is a host that harbors the parasite
only for a short transition period.
-Mosquito, fly
harbors cysts.
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•Vector control
Medication
Vaccination
Genetic engineering?
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