Download MONERANS (bacteria) - Laguna Middle School

MONERANS
(bacteria)
Notes
Bacteria are ancient
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fossil bacteria have been found dating back
3.5 billion years
Bacteria = been around for 76% of earth’s
history
People = been around for 0.004% of
earth’s history
How long is 1 million years?
Ex. You must spend $1,000/day How
long will it take you to spend . . .
$1,000?
 $1,000,000?
 $1,000,000,000

1 day
 2.74 years
 2,740 years
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Bacteria are Everywhere!!
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In water
volcanic vents at the bottom of the sea
in the air
on your skin
in the soil (Actinomycetes gives soil it’s
smell)
How many bacteria are
there?
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There are more bacteria in your mouth than
all the people that have ever lived!
Bacteria may outweigh trees in total
biomass -- How possible? They are found
deep in the soil, on the highest mountains
and in the deepest oceans
Characteristics of Bacteria
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Shapes- round, rod-shaped, spiral, many
others
Colors - red,yellow,blue,tan,orange,
violet and others
Appearance - colonies of bacteria will
appear as slick, wet looking circles of
colored growth
Structure of bacteria
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Bacteria have no nucleus
The hereditary material, RNA, floats freely
in the cytoplasm
Some bacteria have flagella
In addition to a cell membrane and a cell
wall bacteria have a capsule that protects
them
Basic Bacteria Structure
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Flagella
Capsule
Cell Wall
Cell Membrane
Hereditary Material
Cytoplasm
Life functions of bacteria
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Aerobic - use oxygen (most common today)
Anaerobic - does not need oxygen
Magnetotitic - use the Earth’s magnetic
field to stay buried in the mud
heterotrophic - parasites, decomposers
autotrophic - photosynthesis,
chemosynthesis
How tough are bacteria?
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When conditions for growth deteriorate
bacteria can form an endospore. This tough
coating can protect them for a long time.
Example: Dr. Cano at Cal Poly has
removed 20 million year old bacteria from
fossilized amber, put it in optimal growth
conditions and watched as it came back to
life and started growing!
Why are bacteria so
important?
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They are the world’s ultimate recyclers
As decomposers bacteria breakdown dead
organisms returning the molecules from the
organisms
to the soil
so the
cycle of
life can
continue
Bacteria: the + and the 
the positives
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decomposers
added first oxygen to
atmosphere
start soil production
make vitamins
make foods
make antibiotics
base of food chain
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the negatives
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spoil food(fridge
slows down growth)
cause disease
tooth decay
damage roads
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Bacteria Lab
Differential staining
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Different types of bacteria have cell walls
that are structurally different
In this lab, we will see how we can use this
fact to help determine different types of
unkown bacteria