Chapter II Classification and Nomenclature Flashcards
6 Major types of Microorganisms
-bacteria, – archaea, – fungi, – protozoa, – algae, and – viruses.
• unicellular • they lack a nucleus. • they exist in four major shapes: – bacillus (rod shape), – coccus (spherical shape), – spirilla (spiral shape), and – vibrio (curved shape) • have a peptidoglycan cell wall • they divide by binary fission; • and they may possess flagella for motility.
Bacteria
(rod shape)
bacillus
(spherical shape)
coccus
(spiral shape),
spirilla
(curved shape)
vibrio
2 cell wall structure of bacteria
- Gram-positive
* Gram-negative
(living in the presence of oxygen)
aerobic
(living without oxygen)
anaerobic
(can live in both
environments)
facultative anaerobes
2 types of bacteria on how they obtain energy
- Autotrophs
* Heterotrophs
- cell wall structure lack peptidoglycans
* with avidity to extreme environmental conditions.
Archaea
4 types of Archaeans based on their habitat
- methanogens
- halophiles
- thermophiles
- psychrophiles
(methane-producing organisms)
methanogens
(archaeans that live in salty environments)
halophiles
(archaeans that live at extremely hot temperatures)
thermophiles
(cold-temperature Archaeans)
psychrophiles
• eukaryotic cells (with a true nucleus)
• most are multicellular
• their cell wall is composed of chitin
• they obtain nutrients by absorbing organic
material from their environment
(decomposers), through symbiotic relationships
with plants (symbionts), or harmful
relationships with a host (parasites).
•they form characteristic filamentous tubes
called hyphae that help absorb material. The
collection of hyphae is called mycelium
• they reproduce by releasing spores
Fungi
Filamentous tubes that help absorb material.
hyphae
The collection of hyphae is called ______
mycelium
• unicellular aerobic eukaryotes
• they have a nucleus, complex organelles, and
obtain nourishment by absorption or ingestion
through specialized structures
• they make up the largest group of organisms
in the world in terms of numbers, biomass,
and diversity
• their cell walls are made up of cellulose.
Protozoa
5 Classifications of Protozoa
Protozoa, Flagellates, Ciliates, Amoeboids, Sporozoans
Have been traditionally divided
based on their mode of locomotion
Protozoa
Produce their own food and use
their whip-like structure to propel forward
Flagellates
Have tiny hair that beat to produce
movement
Ciliates
Have false feet or pseudopodia
used for feeding and locomotion
Amoeboids
______ are non-motile. They also have
different means of nutrition, which groups
them as autotrophs or heterotrophs.
Sporozoans
• also called cyanobacteria or blue
-green
algae,
• are unicellular or multicellular eukaryotes
that obtain nourishment by photosynthesis.
•they live in water, damp soil, and rocks and
produce oxygen and carbohydrates used by
other organisms.
•it is believed that cyanobacteria are the
origins of green land plants
Algae
• are noncellular entities that consist of a
nucleic acid core (DNA or RNA)
surrounded by a protein coat
• they are not considered living organisms
• they cannot reproduce outside a host cell
and cannot metabolize on their own.
• viruses often infest prokaryotic and
eukaryotic cells causing diseases.
Viruses
A group of eukaryotic organisms consisting of the flatworms and roundworms, which are collectively referred to as the \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
Helminths.
____ is the science of naming,
describing and classifying organisms
and includes all plants, animals and
microorganisms of the world.
Taxonomy
Considered the Father of Taxonomy developed taxonomic
system for naming plants and animals
and grouping similar organisms together.
Carolus Linnaeus
Plural of taxon
taxa
Several taxa of lower rank
– Kingdom (not used by most bacteriologists) – Phylum – Class – Order – Family – Genus (plural: Genera) – Species (both singular & plural)
Based on: • Morphology • Metabolism (Biochemical Activity) • Molecular Techniques • Fatty Acid Profiles • Protein Differentiation • DNA Finger Printing
Whittaker Classification
Based on: • differences in the 16S ribosomal RNA (rRNA) structure • cell’s membrane lipid structure and its sensitivity to antibiotics.
Woese Classification
The first part is the _____ to which the species belongs and the second part is
the ______name.
- Genus
- species name.
The binomial naming system was first uniformly used by _____.
Carl Linnaeus
Generic part is ______, species is _____.
- Generic
- species
Archaea is divided
into two phyla:
– Phylum Crenarchaeota
– Phylum Euryarchaeota
Originally containing thermophylic and hyperthermophilic
sulfur-metabolizing archaea
Phylum Crenarchaeota
Contains primarily methanogenic archaea, halophilic
archaea, and thermophilic, sulfur-reducing archaea
Phylum Euryarchaeota
• very diverse, with all four modes
of nutrition represented
• grouped because of shared rRNA
sequence
• also has endosymbionts such as
nitrogen fixers
• of medical importance are the
chemoheterotrophs
Phylum Proteobacteria
• grow only in eukaryotic host cells
• small phylum containing the genus
Chlamydi
Phylum Chlamidiae
• spiral bacteria
• characterized by flexible, helical cells with a modified outer membrane (the outer sheath) and modified flagella (axial filaments) located within the outer sheath
• important pathogenic genera include
Treponema, Borrelia, and Leptospira
Phylum Spirochaetes
• includes opportunistic pathogens
• includes genera Bacteroides,
Flavobacterium, Flexibacter, and
Cytophyga
Phylum Bacteroidetes
• oxygenic photosynthetic bacteria
• provide an enormous amount of
food for organisms in freshwater
and marine ecosystems
Phylum Cyanobacteria
• low G+C content;
– Bacilli include Lactobacillus,
Streptococcus, Staphylococcus,
Listeria, and Bacillus
– Clostridia includes Clostridium
Phylum Firmicutes
• genetically, high G+C content
– Includes genera Actinomyces,
Streptomyces, Corynebacterium,
Micrococcus, Mycobacterium,
Propionibacterium
Phylum Actinobacteria
Cocci in pairs are called
____.
diplococci
Cocci in chains are called
_____.
streptococci
Cocci in irregular groups
are called ______.
Staphylococci
Bacilli may be arranged in:
-chains
-branching chains
-mass together
-remain attached at various angles
resembling Chinese letters
Rods that are slightly curved
• Vibrios
Polar flagella
• Spirilla
Axial filaments
•Spirochaetes
The term ______ is used for eukaryotes that are not plants,
animal and fungi
Protist
-normally two flagella when present,
with hairlike projections on one of them
- Phylum Oomycota (water molds)
- Phylum Bacillariophyta
(diatoms) - Phylum Chrysophyta (golden algae)
- Phylum Phaeophyta (brown algae)
Kingdom Stramenophila
Characteristics:
sac-like alveoli that form a continuous
layer just under the plasma membrane
- Phylum Dinoflagellata
(dinoflagellates) - Phylum Apicomplexa
(sporozoans) - Phylum Ciliophora (ciliates)
Kingdom Alveolata
Characteristics:
produce elaborate shell-like coverings
of cells; use very slender pseudopodia
to move
- Phylum Foraminifera (forams)
- Phylum Radiolaria
(radiolarians)
Kingdom Rhizaria
Characteristics:
possess “excavating” feeding grooves;
flagellated
- Phylum Diplomonadida
(Giardia lamblia) - Phylum Parabasalia
(Trichomonas vaginalis)
Kingdom Excavata
Characteristics:
Move using relatively large lobeshaped pseudopodia
- Phylum Gymnamoeba
(free-living amoebas) - Phylum Entamoeba
(parasitic amoebas) - Phylum Acrasiomycota
(cellular slime molds) - Phylum Myxomycota
(plasmodial slime molds)
Kingdom Amoebozoa
Characteristics: flagellate cells, such as the sperm of most animals and the spores of the chytrid fungi, propel themselves with a single posterior flagellum.
Opisthokonta
The \_\_\_\_\_ are a broad group of eukaryotes, including the animal and fungus kingdoms. The \_\_\_\_\_\_, are generally recognized as a clade.
opisthokonts
• Decomposers
• Heterotrophic; absorb nutrients. Most
have chitin in cell walls
– The feeding structures of a fungus
are threadlike filaments called
hyphae
– Hyphae branch repeatedly as they
grow, forming a mass known as a
mycelium
– Lichen is a symbiosis between
fungi and green algae
– Mycorrhiza is a symbiosis
between fungi and plant roots.
Fungi
The feeding structures of a fungus
are threadlike filaments called
hyphae
Hyphae branch repeatedly as they
grow, forming a mass known as a
___.
mycelium
___ is a symbiosis between
fungi and green algae
Lichen
______ is a symbiosis
between fungi and plant roots
Mycorrhiza
• with flagellated spores; includes
parasites of other animals
Phylum Chytridiomycota
Chytrids
• have protective zygosporangia,
where zygotes produce haploid
spores by meiosis. Includes bread
molds
• may include microsporidia,
obligate intracellular parasites
Phylum Zygomycota
• form mycorrhizae
Phlyum Glomeromycota
• have asci or sac (sac fungi)
• can be unicellular or
multicellular.
• includes some of the most
devastating plant pathogens,
or in lichen (e.g. morels, cup
fungi, yeasts)
Phylum Ascomycota
• club fungi with spore-producing
basidia
• excellent decomposers
• includes mushrooms and shelf
fungi
Phylum Basidiomycota
– prokaryotic, with peptidoglycan in cell wall, no nucleus; some
disease-causing species
Bacteria
- Proteobacteria – includes coliform (e.g. E. coli), pseudomonads, and vibrios
- Chlamidiae – Chlamydia
- Spirochaetes – includes Treponema, Borrelia, and Leptospira
- Bacteroidetes – includes Bacteroidetes
– Gram – negative
• Firmicutes – clostridia, mollicutes, bacilli (Bacillus, Lactobacillus, Streptococcus,
etc.)
• Actinobacteria – includes Streptomyces and Mycobacterium
– Gram – positive:
with nuclei
Eukaryotes
– includes dinoflagellates, ciliates (B. coli), and
apicomplexans (e.g. Plasmodium)
Alveolata
– includes flagellated protozoans; e.g. Giardia and
Trichomonas
Excavata
– ascomycetes (e.g. Pneumocystis and Candida),
mushrooms, zygomycetes (e.g. microsporidia)
Fungi
– tapeworms (e.g. Taenia), flukes (e.g.
Schistosoma), nematodes (e.g. Ascaris), arthropods (e.g.
mosquitoes, fleas, mites_
Animals
