Download Unit 9 Tax Microbes

Classification & Taxonomy 10-1
Taxonomy: An organized system to classify all
living things, and the study, practice, & science of
the classification of organisms
Target
• List the 8 taxons in order from most to
least inclusive
• Use binomial nomenclature to write a
scientific name
• Use a dichotomous key to identify
organisms and their relationships
• Compare and contrast the 6 kingdoms of
life (based on the BIG 5)
Biology is the study of life… PG 131
• But how do we know
something is “alive”?
– Metabolism
• Consume molecules
• Produce wastes
• Exchange gases
– Reproduction
– Cells
– DNA
The Need for a Classification System…
• Organizing and categorizing all of the organisms that
exist on earth today is quite a task!
• Problems: common names & different languages
• Solutions: A system of classification must be…
- organized and logic
- universal (used by all scientists) use Latin for the
basis of the names
• Our current system breaks down organisms into more & more
closely-related groups until only one group is left…the
“species”!
Binomial Nomenclature
(“to name with 2 names”)
• Each species is named with 2 words
– The first word is the “genus”
– The second word is the “specific epithet”
– When written together, this name is called the
“species”
– Ex: Homo sapiens (usually when typing) or
Homo sapiens (usually when hand writing)
• Homo = genus of humans
• sapiens = specific epithet of humans
• Note: genus is capitalized, other is not…both
underlined (when writing) or italicized (when typed)
Taxons
• Groups of related genera are classified together in the
same family
• Groups of related families for an order
• This follows the pattern…
Orders  Class  Phylum  Kingdom
• We usually memorize these from the largest to
smallest direction:
– Domain, kingdom, phylum, class, order, family, genus,
species
– DKPCOFGS
– Dear King Phillip Called Out For Grape soda!
Test Yourself!
Name the 8 major taxons in order…
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Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Dichotomous Keys
• Rules:
– Always start at clue set #1
– One of the choices must be correct…the other
must be incorrect
– Identify the correct one and go where it says
– When creating a key, it is better to use
“is…is not” format for clues
– Will always have one fewer clue than # of
objects
Dichotomous Key Example
• Example:
• 1. A. contains ink……………..…..go to 2
•
B. does not contain ink………..go to 3
• 2. A. point made of metal………..pen
•
B. point not made of metal……marker
3. A. made of plastic…..mechanical pencil
B. not made of plastic…...regular pencil
Draw on page 138
(Just the Tree part)
All organisms have been placed
into one of 6 kingdoms. 10-2
• This is a generally agreed-upon standard,
but is subject to change
• We have not always had 6 kingdoms, and
some scientists use fewer or more
• What criteria are used to place an
organism in a kingdom?
Basic Criteria for Kingdoms
(The Big 5!) 10-2
• # of Cells
– Unicellular or Multicellular
• Type of Cell
– Prokaryotic or Eukaryotic
• Cell Wall
– Yes or No (if yes, then state the composition)
• Nutrition
– Autotrophic or Heterotrophic
• Motility
– Yes or No
Test Yourself!
What do the following mean? If you do
not write down the definitions!
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Unicellular
Multicellular
Prokaryotic
Eukaryotic
Autotrophic
Heterotrophic
Motile
Non-motile
Cell Wall
Bacteria
• The Big 5:
• Domain Archaea
– K. Archaebacteria
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Harsh environments
Methanogens (anaerobic)
Thermophiles (high heat)
Halophiles (salt)
• Domain Eubacteria
– K. Eubacteria
• “common” bacteria
• Ex: E.coli; Staphylococcus aureus
– Unicellular
– Prokaryotic
– The other 3
traits are
variable…
examples of
bacteria exist
for each trait
(cell wallpeptidoglycan)
Domain Eukarya
• Includes the following
kingdoms:
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PROTISTA
FUNGI
PLANTAE
ANIMALIA
K. Protista
• The most diverse and
oft-changing kingdom!
• The Big 5:
– Unicellular*** (mostly)
– Eukaryotic
– The other 3 traits are
variable…protists of
various types exhibit
both versions.
K. Fungi
• Often seem plant-like…but
cannot make food!
• The Big 5:
– Multicellular
– Eukaryotic
– Cell wall – of chitin
– Heterotrophic – absorb food
– Nonmotile
K. Plantae
• Usually green due to
chlorophyll
• The Big 5:
– Multicellular
– Eukaryotic
– Cell wall – of cellulose
– Autotrophic
– Nonmotile
K. Animalia
• Large, motile creatures
that eat!
• The Big 5:
– Multicellular
– Eukaryotic
– No cell wall
– Heterotrophic – ingest
food
– Motile
Bell Ringer
• A Key to New Pamishan!
– This is individual work!
– Show me when you are finished
– Do not write on the dichotomous key! Just in
your notebook
Taxonomic Tree
Which group of organisms are most closely related?
Butterflies, moths and flies
Taxonomic Tree 10-3 pg 130
• Cladistics- classification system based on phylogeny;
assumes that as groups of organisms diverge and
evolve from a common ancestral group, they retain
derived traits.
• Cladogram is the diagram used to represent the
phylogeny of a species based on those derived traits
• Work on 10-3 as a table group
X
Y
Z
1. A. Is multicellular………………………………..go to 2
B. Is unicellular……………………….…………go to 3
2. A. Contains chlorophyll; is green…………….Chlorella
B. Contains erythrophyll; is red………………Hemalia
3. A. Cell is oblong with tiny cilia………………...Paramecium
B. Cell is blob-like with slender extensions….Amoeba
Target
• Use a dichotomous key to identify
organisms and their relationships
• Identify various bacteria based on shapes
and groupings
• Describe the harmful and helpful impact of
bacteria
Taxonomic Classification
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Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Anura
Family: Ascaphidae
Genus: Ascaphus
Specific epithet: montanus
Scientific name: Ascaphus montanus
http://calphotos.berkeley.edu/cgi/img_qu
ery?enlarge=0000+0000+0601+0118
Bacteria 10-4 pg 133
The First Cells
Bacteria are grouped
into one of 2 Kingdoms
• What is the difference between them?
– K. Archaebacteria
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Harsh environments
Methanogens – no O2; marshes; cow gut
Halophiles – high salt; dead sea; great salt lake
Thermophiles – high heat; thermal vents of
oceans
– K. Eubacteria
• Common bacteria, found all around us
The Big “5”
Type of cell
- prokaryotic
# of cells
- unicellular
Cell wall
- murien or peptidoglycan
– The other 2 traits are variable… examples of
bacteria exist for each trait
What structures do all bacteria have?
• ALL have…
– Cell membrane, ribosomes, DNA, cell wall
semipermeable membrane, site of mRNA translation and protein synthesis,
genetic material, polysaccharides surrounding cell
• SOME have…
– Flagella, pili, capsule, endospore
Movement, attachment to surfaces, gelatinous covering, resist destruction
Test Yourself!
What do each of the structures listed
above do?
What structures do all bacteria
have?
How do we classify bacteria?
• Based on SHAPE:
– Coccus- round cells
– Bacillus- rod cells
– Spirillum- spiral cells
How do we classify bacteria?
• Based on GROUPINGS:
– Diplo- (pairs)
– Staphylo- (clusters)
– Strepto- (chains)
Test Yourself!
What would these look like?
• Diplobacillus
• Streptococcus
• Staphylococcus
• Diplospirillum
How do bacteria reproduce?
• 1. Binary fission
– Asexual (genetically same)
– Copies DNA & splits into 2 cells
– Very fast!
How do bacteria reproduce?
• 2. Conjugation
– Sexual (genes
recombine)
– Transfer DNA
through tube
Why are some bacteria so tough to kill?
10-5
• Endospores
– Tiny structures with tough coatings
– Resist high temps, dryness, & chemicals
– Holds copy of genes
– Ex: Clostridium botulinum (botulism food
poisoning)
How do bacteria respire? 10-5
AEROBIC
• Those that requires
OXYGEN (O2)
• Example: Mycobacterium
tuberculosis, attacks the
lungs
ANAEROBIC
• Those that DO NOT
require oxygen (O2)
• Many are actually
poisoned by O2
• Ex: Clostridium tetani,
causes tetanus
What are some beneficial impacts
& uses of bacteria?
• 1. nitrogen-fixation – pull N2 from air & add
to soil (N needed to make proteins)
• 2. decomposition – break down dead stuff
• 3. O2-production – blue-green bacteria
• 4. food production – cheeses, pickles, yogurt,
etc
• 5. human digestion – vitamin K
• 6. antibiotics – ex. Streptomycin & acromycin
• 7. Genetic tech- use to make chemicals
What are some harmful effects of
bacteria?
• 1. Crop damage
– Food spoilage
• 2. Livestock diseases
– Foot & mouth disease, zoonosis, anthrax
• 3. human disease
– Strep throat; tetanus; TB; pneumonia; Lyme
disease; dental cavities; food poisoning;
chlamydia; syphilis; gonorrhea
How do we defend ourselves
against bacteria?
• Non-specific immunity
ex. Skin cell barrier
antimicrobial fluids (tears, oils, wax)
white blood cells
• Antibiotics
ex. Penicillin, streptomycin
Penicillin “pokes” holes in the cell membrane
Streptomycin disrupts protein synthesis
Viruses 10-6 pg 134
Are they alive?
No! Considered nonliving!
Target
• Compare and contrast the events of the
lytic and lysogenic cycles
• Recognize examples of common viral
infections
What is a Virus?
• Structure that contains genetic material
(DNA or RNA) wrapped in protein (capsid)
• Has NO cells
– Does NOT: breathe (gas exchange), eat,
produce wastes
• Can reproduce, but only if in a host cell
Types of Viruses
Considered a
RETROVIRUS
Same as Ebola!
Structure of a Virus
How do viruses invade cells?
• 1. Virus attaches to
host cell’s membrane
– is very specific to
certain cells
– Ex: cold virus can only
attach to respiratory
cells
• 2. Virus shoots or
injects its DNA into
the host cell
Viral Reproduction
How do viruses replicate?
Lytic Cycle
– Virus DNA takes over cell
immediately
– New virus parts are made
– Host cell bursts releasing
new viruses to infect
nearby cells
– Has a short “incubation
time”
– Ex: flu, cold, measles
Lysogenic Cycle
– Viral DNA “hides out” within
host’s DNA
– Virus DNA gets copied
every time host cells copy
– At some point, virus goes
into lytic cycle and kills host
cells
– Has long incubation time
(months-years)
– Ex: HIV, warts, shingles,
herpes
Virus Lytic Cycle pg 135
Lytic Cycle pg 135
Lysogenic Cycle
Viral Reproduction
HIV Life Cycle
HIV attacks the
very system in our
bodies that we use
to fight infections.
*destroys/inhibit
T cell production
Virus Evolution
• What makes a virus a “smart” or “successful”
virus?
– A smart virus is one that does not kill its host right
away; moreover, a smart virus wants to be able to
survive and reproduce for as long as possible without
killing its host.
From an evolutionary standpoint, is Ebola a “smart”
virus?
• What would Darwin say???
How to fight off a virus?
• We cannot use antibiotics because… they
target cells
• Vaccines… these are used to stop
infection
• Use broken viruses to trick the body into
making an army to “kill virus”
• If infected only your immune system will
fight!
Part 3: Protists 10-7
PG 134
Kingdom Traits
• All are eukaryotic
• Most are unicellular
– (with exception of the algae)
• Most diverse kingdom!
– Very few traits that all protists share…some are
animal-like, some plant-like, some fungus-like
– Has actually been sub-divided into more than one
kingdom…but we will keep it as one
Types (based on how get food)
• Animal-like
– Heterotrophic, motile
– Ex: Amoeba, Paramecium
Types (based on how get food)
• Plant-like
– Autotrophic
– Some unicellular, some multicellular
– Ex: Euglena, algae
Types (based on how get food)
• Fungus-like
– Heterotrophic, nonmotile
– Unicellular, but join in blobs
– Ex: slime molds, water molds
Harmful Effects of Protists
• Disease
– Malaria
• Protists carried by
mosquitoes
– African Sleeping
Sickness
• Protists carried by Tsetse
Flies
– Giardiasis
• Ingesting contaminated
food, soil, water
Helpful Aspects of Protists
• Oxygen to atmosphere
– Green algae do photosynthesis
• Food source in oceans
– Plankton are base of aquatic food chains
• Act like decomposers
Part 4: Fungi 10-7 pg134
Structure of Fungi
• Multicellular, eukaryotic, non-motile
• Cell walls made of chitin
• Heterotrophic (absorb food!)
– Have filaments called hyphae…used to anchor,
feed, & reproduce
– Network of hyphae called a mycelium
– Secretes enzymes
• Habitat = everywhere! (but usually moist
areas)
Examples of Fungi
• Mushrooms
• Moldssaprophytes
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Yeast
Shelf fungi
Morels
Lichenmutualists
Harmful Effects
• Disease
– Athlete’s foot; yeast
infections; toenail
fungus (parasites);
ringworm; etc
• Crop/food damage
– Plants hit especially
hard
– Cattle diseases
Helpful Effects
• Decomposers
– Break down dead stuff
• Some antibiotics (penicillin)
• Food products
– Yeast = breads, beer, etc
– Some cheeses; mushrooms
• Biotechnology
How do fungi get their food?
• Secrete enzymes into surrounding matter…
hyphae soak up nutrients
• Is extracellular digestion… absorb nutrients
after they have been broken down
How do fungi get their food?
• Grouped according to where they get food:
– Saprophytes…from dead stuff (ex: mold on food)
– Mutualists…symbiotic relationship (ex: lichen)
– Parasites…from living organisms (ex: toe fungus)
How do fungi reproduce?
Write under the picture or on nb paper
• Asexually (no
transfer of DNA)
– Fragmentation –
pieces break off &
grow into new fungi
bodies
– Budding – new cell
pinches off from old
one (occurs in
yeasts)
How do fungi reproduce?
Write under the picture or on nb paper
• Sexually (transfer of DNA)
– Spores are reproductive cells
that turn into new fungi bodies
– Very large # of spores made;
are small & light for easy
dispersal
Quiz - Microbes
Use your own paper.
Do not write the question.
Does not need to be in complete sentences.
Quiz - Microbes
• 1. The method of asexual reproduction in
bacteria is called –
– A. conjugation
– B. sporulation
– C. budding
– D. binary fission
Quiz - Microbes
• 2. Which is a spirillum?
• 3. Which is a bacillus?
• 4. Which is a coccus?
A
B
C
Quiz - Microbes
• 5. The large, rounded structures shown within
the bacterial cells below are –
– A. capsules
– B. cell walls
-- C. endospores
-- D. pili
Quiz - Microbes
• 6. List three helpful things that bacteria do or
provide.
• 7. List two diseases caused by bacteria.
• 8. Of viruses and bacteria – which is easier to treat
with antibiotics?
• 9. What is penicillin actually doing when it kills a
pathogen?
Quiz – Microbes (alternate
ending)
• 6. List three helpful things that bacteria do or
provide.
• 7. How does the lysogenic cycle of viruses differ
from the lytic cycle?
• 8. Explain the importance of nonspecific immune
defenses. List 2 particular types of nonspecific.
• 9. What is meant by “specific immune response” as
related to your immune system?