Transcript Bacteria Powerpoint

Kingdom
Archaebacteria
Both kingdoms of bacteria have species that are
microscopic; humans can’t see them unless we
stain them and then look at them under the
microscope. The pictures you see are magnified
many times!!
Background
• Biologists have long
organized living things
into large groups called
kingdoms.
• There are six of them:
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Archaebacteria
Eubacteria
Protista
Fungi
Plantae
Animalia
5 common characteristics used for
comparison among living organisms:
• Cell type – 2 kingdoms are prokaryotic; 4
kingdoms are eukaryotic
• Cell wall – 4 of the 6 kingdoms have a cell
wall
• Body type – unicellular vs. multicellular
• Nutrition – autotrophic vs. heterotrophic
• Reproduction – sexual vs. asexual
Some recent findings…
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In 1996, scientists decided to split Monera into
two groups of bacteria:
Archaebacteria and Eubacteria
Because these two groups of bacteria were
different in many ways scientists created a
new level of classification called a DOMAIN.
Now we have 3 domains
1. Bacteria
2. Archaea
3. Eukarya
• “ancient” bacteria
• Some of the first
archaebacteria
were discovered
in Yellowstone
National Park’s
hot springs and
geysers.
• Prokaryotes are
structurally
simple, but
biochemically
complex
The Domain
Archaea
Basic Facts
• They live in extreme environments (like
hot springs or salty lakes) and normal
environments (like soil and ocean
water).
• All are unicellular (each individual is
only one cell).
• No peptidoglycan in their cell wall.
• Some have a flagella that aids in their
locomotion.
Some weird things about this
kingdom…
• Most don’t need oxygen to survive
• They can produce ATP (energy) from sunlight
• They can survive enormous temperature
extremes
• They can survive high doses of radiation
(radioactivity)
• They can survive under rocks and in ocean
floor vents deep below the ocean’s surface
• They can tolerate huge pressure differences
3 Main Types
Methanogens
Thermoacidophiles
Halophiles
• They release methane
(CH4) as a waste product
• Many live in mud at the
bottom of lakes and
swamps because it lacks
oxygen
• Some live in the intestinal
tracts of animals to help
break down food
• Others like to hang out in
the stomach
• Your intestinal gas is a
waste product caused by
bacteria in the body
breaking down the food
you eat—that’s why farts
don’t smell sweet!
Methanogens
Significance of methanogens
• They could play a role in
garbage/sewage cleanup
by having methanogens
eat garbage.
– The methane waste the
bacteria produce after
eating the garbage or
sewage could be used
as fuel to heat homes.
• Some landfills already
employ this method—the
only problem is that it’s
expensive.
Thermoacidophiles
• Live in the dark
• Live without oxygen
• Like to live in superheated water with
temperatures reaching 750 deg F
• Prefer environments that are very acidic (between
pH of 1-3)
• Live in a chemical soup of hydrogen sulfide (H2S)
and other dissolved minerals (rotten egg smell)
Thermo = temperature
Acidophil = acid loving
Black Smokers
The interior layers of the Earth are
made up of many different types of
metals (iron, copper). The black color is
caused by a chemical reaction of the
metals with the ocean water. In
extreme temperatures and pressures,
this is where some thermoacidophiles
like to live.
Other thermoacidophiles like to live in hot springs or
geysers. Hot springs are pools of hot water that have
moved toward earth's surface. The source of their
heat is the hot magma beneath and they can reach
temperatures as high as 400 degrees Fahrenheit
http://www.nps.gov/archive/yell/oldfaithfulcam.htm
Old Faithful erupts more frequently than
any of the other big geysers. Its average
interval between eruptions is about 91
minutes. An eruption lasts 1 1/2 to 5
minutes, expels 3,700 - 8,400 gallons of
boiling water, and reaches heights of
106 - 184 feet.
Halophiles
• Can live in water
with salt
concentrations
exceeding 15%
• The ocean’s
concentration is
roughly 4%
• Halo = salt
phil = loving
The Great Salt Lake in Utah
The Great Salt Lake in Utah
• It is interesting to note that the Great Salt Lake is
actually three to five times saltier than the
ocean.
• Every year, members of the salt industry extract
about 2.5 million tons of sodium chloride (salt,
NaCl) from the lake.
• The Great Salt Lake has no fish. The largest
aquatic critters in the Great Salt Lake are brine
shrimp.
• Given that the salty water can be corrosive to
metal, motorized boats are not very popular at
Great Salt Lake State Park. Additionally, since
the salt content of the Great Salt Lake increases
the water’s density, water skiing and jet skiing is
not very common.
Kingdom
Eubacteria
“true bacteria”
Bacteria vs. Eukarya
Bacteria
Eukarya
Internal
compartmentalization
No nucleus, few
organelles
Nucleus with many
organelles
Cell size
Very small; microscopic Small; still microscopic
but 10 to 100 times
bigger than bacteria
Number of cells
unicellular
multicellular
Chromosomes
Single, circular DNA
strand
Many chromosomes
made up of DNA
Reproduction
Asexually by binary
fission
Sexually by mitosis and
meiosis
Flagella
Common in most
species
Seldom seen in
species; longer and
stronger than bacteria
Metabolic diversity
Can survive with or
without oxygen
Require oxygen to
survive
Bacterial Cell Shapes
Bacillus (rod-shaped)
Coccus (round-shaped)
Spirillum (spiral-shaped)
Obtaining Energy
• Most scientists classify bacteria based on
how they obtain energy:
Photosynthesizers
Chemoautotrophs
Heterotrophs
• A significant fraction
of the world’s
photosynthesis is
carried out by
bacteria
• Cyanobacteria are
blue-green bacteria
that contain
chlorophyll in their cell
membrane
• Cyanobacteria are
thought to have made
the Earth’s oxygen
atmosphere
Photosynthesizers
Chemoautotrophs
• Breakdown chemicals
found in the soil; they
use those chemicals
for nutrition
• The bacteria’s waste
products act as
fertilizer and helps
with agriculture
• A handful of soil can
have up to 10 billion
bacterial organisms
• Most types of
Eubacteria are
heterotrophic
• Together with
fungi, they serve
as primary
decomposers for
the environment by
releasing nutrients
back to the soil
after living things
have died.
Heterotrophs
Pathogenic Bacteria
• Your body is a treasure chest of wealth
just waiting to be discovered by bacteria.
• Bacteria have evolved various ways of
entering your body and taking what they
need in order to survive
• In some cases, the competition for the
resources in your body can result in you
becoming ill.
Bacteria are harmful in two ways:
1.
#1 - Bacteria can
metabolize their host by
using different parts of
the body as their food
source.
Tuberculosis is a less
common bacterial
infection that attacks the
lungs of humans.
Mycobacterium tuberculosis
is the bacteria that uses
the lung tissue as a food
source.
The warm, moist environment
allows the bacteria to
reproduce and populate
the lungs.
#2 - Bacteria cause disease by secreting chemical
compounds called toxins into their environment.
Humans are most affected when food is not properly
prepared. Food poisoning is the common name
given to people who get severely sick after eating
something that wasn’t cooked well.
Most types of toxin bacteria can be killed by boiling
water and cooking foods at recommended
temperatures.
Kitchen and surface antibacterial products also help
in ridding our house of these relentless pests.
• In 1928, Alexander
Fleming noticed a fungus
growing on a Petri plate
that was growing bacteria.
• He saw that the bacteria
did not grow near the
fungus.
• He concluded that the
fungus was secreting a
substance that killed the
bacteria.
• He later called the
secretion penicillin.
• Penicillin is one of many
medicines that help fight
bacterial infections.
Antibiotics
Antibiotic-Resistant Bacteria
Problem #1:
• Because bacteria can multiply very quickly, a 710 day course of antibiotics might not kill all of
the bacteria.
• The bacteria that remain become resistant and
may mutate their DNA and reproduce more
cells.
• The new cells are now resistant to the antibiotic
and make it harder to treat an infection the next
time around.
Problem #2:
• Another problem in
society is related to
people not taking their
prescribed course of
pills.
• Sometimes if people
start to see
improvement in their
symptoms they stop
taking their
medication.
• This leaves more
opportunity for the
bacteria not yet killed
by the antibiotic to
reproduce and create
resistant cells.
Problem #3:
• Do antibacterial
soaps really work?
• Regular, routine use
of these types of
soaps may be doing
more harm then good.
• The bacteria that are
commonly found on
our skin may become
resistant to the
antibacterial
chemicals put in the
soaps.
We’ve talked about why bacteria is BAD…Is
there anything GOOD about bacteria?
• Act as decomposers
• Live within our digestive
tract (called probiotics)
• Many foods we eat are
processed by bacteria
(pickles, buttermilk,
cheese, sauerkraut,
olives, vinegar, etc.)
• Bacteria can be used in
mines to breakdown the
surrounding rock and
leave behind the useful
ore/metal.