Transcript Look Mom! No organelles!!!!! (except for ribosomes…why???)

Kingdom Monera
• All prokaryotic
• Unicellular
• Metabolically the most diverse
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Photosynthetic autotrophs
Chemosynthetic autotrophs
Chemosynthetic heterotrophs
Photosynthetic heterotrophs
Obligate anerobes
Facultative anaerobes
• Members include bacteria and blue-green bacteria
• Extremophiles
Ecological/Economic Importance
• Ecologically, monerans are major
decomposers in the world’s ecosystems
• Many have symbiotic relationships: some
mutualistic, some parasitic
• Economically they can be used in food
production, in the manufacture of artificial
snow, in mining, and in biotechnology in
the manufacture of pharmaceuticals
Basic Anatomy of the Prokaryote
Look Mom!
No organelles!!!!!
(except for ribosomes…why???)
Some bacteria have plasmids
Plasmids are used in biotechnology to carry
foreign genes into bacterial cells
The cell walls of prokaryotoes
• contain a unique
substance called
peptidoglycan
• This substance is found
only among prokaryotes
• The thickness of the
peptidoglycan layer helps
to differentiate between
types of bacteria
Bacterial Shapes
• Bacteria can be classified according to
three main shapes:
– Round bacteria (cocci)
– Rod shaped bacteria (bacilli)
– Spiral shaped (spirilla)…
Anthrax
The Gram Stain
• Used to help distinguish types of bacteria
• Gram positive (appear purple when
stained)
• Gram negative (appear pink when stained)
• Those bacteria with thick peptidoglycan
layers will stain purple (Gram +) because
the thick layer retains much of the stain
Anthrax
Comparison of Gram positive and
Gram negative bacteria
“Scalded Skin Syndrome”
(a type of “staph” infection)
Avert your eyes if you are
squeamish!!!!!
Reproduction by
binary fission
But can do some other cool genetic
rearrangements…
Bacterial conjugation
transduction
transformation
Bacterial Endospore
Controlling bacterial growth
• Sterilization by using an autoclave (or
pressure cooker)-the only way to kill all
bacteria
• Antibiotics
• Temperature (freezing will stop bacterial
growth but not kill the bacteria;
refrigeration will only slow down the
growth
Microbes: The unseen majority on Earth
Did you know that microbes :
- By weight, represent 60% of the biomass of all life on Earth
- Are found everywhere on Earth, but are largely unculturable
- Constitute more cells in the human body than human cells
- Are the oldest form of life on Earth (~ 3.8 billion years)
- Produce more than 1/2 of all the oxygen we breathe
- Can cause disease, but the vast majority do not...
The Domain Bacteria and Domain
Archea
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Peptidoglycan wall
One kind of RNA
Introns rare
No histones on DNA
Circular chromosome
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Absent
Many kinds of RNA
Present in some
Histones
Circular chromosome