Objective 1.1: Identify unicellular
organisms, including bacteria & protists,
by their methods of locomotion,
reproduction, ingestion, excretion, and
effects on other organisms.
Invention of the microscope led to
discovery of unicellular organisms.
Advances in technology have led us to
discover the good & bad of
microorganisms, benefiting the world.
How we divide the unicellular
organisms:
Organisms are put into domains &
kingdoms based on 3 things:
Cell type: prokaryotes or eukaryotes
Ability to make food: heterotroph or
autotroph
Number of cells in bodies: unicellular (1 cell)
or multicellular (many cells)
3 Domains
Bacteria: prokaryotes (no nucleus),
autotrophic or heterotrophic, microscopic
Archaea (Archeabacteria): prokaryotes (no
nucleus), autotrophic or heterotrophic;
microscopic; no cell walls; extreme
environments (hot, cold, salty, acidic)
Eurkarya: eukaryotes, nucleus; in 4
kingdoms—protists, fungi, plants, or
animals
Domain: Prokarya, Kingdom:
Eubacteria
Many are decomposers that break
down dead organisms & wastes.
Some are producers, making their
own food
Use conjugation or binary fission to
reproduce
Conjugation in E. coli bacteria
Here you can
conjugation—transfer
of genetic material
through a threadlike
bridge—it’s bacterial
sex.
http://www.google.com/imgres?imgurl=http://static.flickr.com/88/210973649_b75e67726a.jpg&imgrefurl=http://scienceblogs.com/mikethemadbiologist/2006/12/it
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8&ei=XjaTeTaEcL10gHC8LimBg&prev=/search%3Fq%3Dconjugation%2Bin%2Bbacteria%2B%252B%2Be%2Bcoli%26um%3D1%26hl%3Den%26rlz%3D1T4TSHB_en
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age=1&ndsp=28&ved=1t:429,r:0,s:0
Binary fission in E. coli bacteria
asexual reproduction
in which the cell
basically copies itself
and undergoes cell
division—special type
of mitosis
http://scienceray.com/biology/microbiology/e-coli-bacteria/
Domain: Eurkarya, Kingdom:
Protista (the protists)
CANNOT be classified as plant, animal, or
fungus
“odds and ends” kingdom
Mainly unicellular others multicellular, so it
is usually referred to as singlecelled/unicellular
Classified by the way they get energy-some autotrophs others heterotrophs
Examples of Protists
Euglena:
use flagella
to move
Amoeba:
Use pseudopods
(false feet; cytoplasmic
Extensions to move)
How protists like the Euglena and
Amoeba reproduce
Both of these organisms reproduce
asexually by binary fission—a special
type of mitosis.
Can produce ENDOSPORES when
conditions are bad, preventing the
species from extinction.
Picture of a typical endospore, used
by bacteria & protists
Remain dormant until conditions in the
environment are favorable for development
An endospore
is a tough, resistant
structure used for
survival during
conditions not
favorable for
reproduction
Examples of Protists
Paramecium
Use cilia—hair-like
projections around
its body to
move
Reproduce sexually by conjugation & asexually by
binary fission.
Reproduce with endospores when times are bad.
Getting food & dumping wastes in
protists
Animal-like protists ingest their food—the process is called
ingestion—surrounding it with pseudopods or engulfing it
and trapping it in a food vacuole for digestion, a process
known as endocytosis.
http://www.ibiblio.org/virtualcell/textbook/chapter3/cmf4a.htm
for endocytosis animation by amoeba
http://highered.mcgrawhill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/007243731
6/120068/bio02.swf::Endocytosis%20and%20Exocytosis
Contractile vacuoles keep these single-celled animals from
exploding due to excess water that collects in their
cytoplasm due to osmosis. They collect the excess water &
then excrete it—the process is called excretion.
All organisms dump wastes through
this process
Exocytosis—think ex = exit
this is the process where unwanted materials in
the cell are literally dumped out of the cell. this
may be through contractile vacuoles, diffusion,
or in more complex structures such as those of
the paramecium, the anal pore.
http://www.ibiblio.org/virtualcell/textbook/chapte
r3/cmf4b.htm for exocytosis animation
Plant like protists: algae, producers
Domain Eukarya, Kingdom Fungi
Multicellular eukaryotes except yeasts
which are unicellullar
Heterotrophs, can act as
decomposers
Absorb nutrients to get energy
Cell walls present
Reproduce using endospores
Examples: molds, yeasts, mushrooms
Fungi Examples
Yeast (Candida albicans)
Fungi Examples
Bread mold, Rhizopus, the happy
accident of penicillin
Examples of Fungal Spores
Mushroom spores
Toxic molds: Stachybotrys
chartarum or Stachybotrys atra