Transcript Aqua Cave Template

UNIT 3 –
MICROBIOLOGY
Where did we come from?
DO NOT COPY… For Entertainment Purposes Only!
The Beginnings of Life
• The earth is ~ 4.567 billion years old
• Think of the earth’s history as one 24h period
(each second = 53 000 yrs)
• The universe began 2 days ago (14 billion y.a.)
• First signs of life at 3 am: “replicator” (4 billion y.a.)
• First prokaryotic cell at 5:20 am (common ancestor)
(survived in CO2 and water)
• 8 am – Organisms began to use light as an energy
source – photosynthesis (oxygen was produced
and was toxic!)
• Oxygen and UV combine to create the ozone
layer…the atmosphere was formed!
Early days on planet Earth
The Beginnings of Life
• 2 pm – Bacteria and
Archaea, and eukaryotes
combine…endosymbiosis
• Small organelles like
mitochondria and
chloroplasts fuse into larger
cells.
• 6:15 pm – plant, animal,
fungi lines begin to form
• 7:15 pm – Multicellular
plants and water animals
form
• 10:12 pm - (340 million y.a)
the evolution of the amniotic
egg allowed eggs to be laid
on land.
The super-continent Pangea
The Beginnings of Life
• 2 seconds before
midnight–
Homo sapiens arise
HOW MANY ORGANISMS?
• 287,655 plants,
including:
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15,000 mosses,
13,025 ferns,
980 gymnosperms,
199,350 dicotyledons,
59,300 monocotyledons;
• 74,000-120,000 fungi;
• 10,000 lichens;
HOW MANY ORGANISMS?
• 1,250,000 animals,
including:
– 1,190,200 invertebrates:
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950,000 insects,
70,000 molluscs,
40,000 crustaceans,
130,200 others;
– 58,808 vertebrates:
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29,300 fish,
5,743 amphibians,
8,240 reptiles,
9,934 birds,
5,416 mammals.
BIODIVERSITY
The Amazon – An example of
Biodiversity
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1 million insect species.
Tens of thousands of plants.
2000 birds and mammals.
To date, at least 40,000 plant
species, 3,000 fish, 1,294 birds,
427 mammals, 427 amphibians,
and 378 reptiles have been
classified.
Scientists have described between
96,660 and 128,843 invertebrate
species in Brazil alone.
One square km may contain over
75,000 types of trees.
One square km can contain about
90,790 tons of living plants.
This constitutes the largest
collection of living plants and
animal species in the world.
One in five of all the birds in the
world live in the rainforests of the
Amazon.
The Amazon – Under Seige
• 1/5 has been
destroyed
• Between 1991 and
2000 an area 2x
the size of Portugal
has disappeared.
• 52 000 square Km
are disappearing
per year…mostly
for cattle farms.
It is
estimated
that we
are losing
140 000
species a
year!
MORE NUMBERS…
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Organism Number
Estimated # to be
Discovered
Viruses 5,000
Bacteria 4,000
Fungi 70,000
Protozoans 40,000
Algae 40,000
Flowering plants 250,000
Roundworms 15,000
Mollusks 70,000
Crustaceans 40,000
Spiders and mites75,000
Insects 950,000
Vertebrates 45,000
500,000
400,000-30 million
1.5 million
100,000-200,000
200,000-10 million
300,000-500,000
500,000-1 million
200,000
150,000
750,000-10 million
8-10 million
50,000
CLASSIFYING LIVING THINGS
• We have a lot of critters to organize!
• The science of classifying organisms, called
TAXONOMY, has 2 purposes:
– Categorize (organize) all living things
– Speak in a language that every scientist can
understand (unifying system)
• Present system developed by Karl von
Linne (Latin = Carolus Linnaeus)
• System based on an organism’s structure
• The more features in common, the closer
the relation.
HOW DO BIOLOGISTS
KEEP TRACK OF ALL
THESE ORGANISMS?
CLASSIFYING LIVING THINGS
Linnean System of Classification
• Binomial nomenclature…
– The first part of any scientific name is
called the genus. A genus may be used
alone. First letter capitalized. (Written in
italics.)
– The second part is called the species and
is never used alone. (Written in italics.)
– Eg. Canis lupis, Escherichia coli (E. coli)
TAXA
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Kingdom
Phylum
Class
Order
Family
Genus
Species
Less similar (broad category)
Very similar (narrow category)
• Each different level of hierarchy is called a taxon
• “King Philip Could Order Four Good Salads”
Classification:
Kingdom Animalia
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Cells do not have cell walls
All are multicellular
All are Heterotrophs
Most reproduce sexually
Live in terrestrial and
aquatic habitats
• Includes invertebrates (no
backbone) and vertebrates
(have backbone)
• e.g. Clam, fish, turtle, cat,
human
Kingdom Plantae
• Cell walls contain
cellulose
• All are multi-cellular
• Autotrophs
• Most reproduce
sexually and
asexually
• Have chloroplasts
• e.g. Mosses, ferns,
seed plants
Kingdom Archaebacteria
• Prokaryotic
• heterotrophs
• Bacteria that live in
extreme conditions
• e.g. Bacteria in
volcanoes
Kingdom Eubacteria
• Simple organisms
lacking nuclei
(prokaryotic)
• Either Heterotrophs
or autotrophs
• Can reproduce
asexually
• Bacteria that are
found everywhere
• E.g. E. coli
Kingdom Protista
• Found many places,
some terrestrial, some
aquatic
• Some have
chloroplasts
• Most are single celled.
• Some are autotrophs,
some Heterotrophs,
some both
• Reproduce sexually
and asexually
• e.g. Amoeba,
Paramecium
Kingdom Fungi
• Similar to plants but
unable to carry out
photosynthesis
• Heterotrophs
• Most are multicellular
• Have cell walls but not
made of cellulose
• Reproduce sexually
and asexually
• Most are terrestrial
• e.g. Yeasts, moulds,
mushrooms
So…
How do we
classify???
Dichotomous Classification Keys
Choose your own adventure!
• Used to help place
organisms into
appropriate groups.
• Each key includes two
choices for each
characteristic.
• No two keys are the
same.
• WARNING…Do not
classify based on the
behavior of the
organisms…just their
structure!
A Classification Tree of the Six Kingdoms:
All Living Organisms
Prokaryotic?
YES
NO
Live in harsh
environment?
YES
Archaebacteria
Eukaryotic cells: Are they multi-cellular?
NO
NO
Protista
YES
Eubacteria
Cell Wall?
YES
NO
Animalia
Wall of Cellulose?
YES
NO
Plantae
Fungi
YOU TRY IT!!
• Make a classification tree using 10
items!
• When done, exchange with someone
else and see if it works!
• If totally done… Try Text Activity!!!