Download Kingdom Monera - Monerans are single celled, prokaryotic

Kingdom Monera
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Monerans – are single celled, prokaryotic organisms.
o Remember that a prokaryote has no nucleus and no double membrane
organelles
There are 4 phyla (singular = phylum) that you need to know
o 1 – Phylum Eubacteria – the “true bacteria”
All have a cell wall, cell membrane, cytoplasm, circular DNA, ribosomes
and one or more flagella
Flagella – long microtubules used for movement
There is a lot of diversity in eubacteria
• Some are even photosynthetic
o 2 – Phylum Cyanobacteria – were once called “blue-green algae”
Are photosynthetic
• Have green pigment – chlorophyll
• Also have blue pigment – phycocyamin
• May also have other pigments ∴ will have different colours
They can be found in water (salt and fresh) and on land
They can be found in all temperature ranges
• From ice to volcano
o 3 – Phylum Archaebacteria – also called “methanogens” because they produce
methane
Are all anaerobic
Have a different cell wall and cell membrane than eubacteria
Are believed to be very similar to the very first cells on the planet.
o 4 – Phylum Prochlorobacteria – are all photosynthetic
Are more similar to photosynthetic plants than cyanobacteria
Identification of Bacteria (Eubacteria)
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Because of the diversity among bacteria, there are many different ways to classify
bacteria
o 1 – Cell shape –
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There are 3 basic cell shapes
• A – Bacilli – rods
• B – Cocci – spheres
• C – sparilla – spirals
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Bacteria in any of these shapes can live as individuals, can form chains or
colonies of bacteria
2 – Cell wall –
The chemical nature of the cell wall allows for 2 types of identification
• A stain is used, and the bacteria cell wall will either absorb or not
absorb the stain
• Ex) G+ or Gram positive – absorbs the stain
• Ex) G- or Gram negative – does not absorb the stain
3 – Movement –
There are 4 basic types of movement for bacteria
• A – Flagella – with 1, 2 or many flagella
• B – Shake-like movement – bacteria spiral forward
• C – Glide – on a slime that the bacteria produce
• D – no movement
4 – Obtaining Energy –
Bacteria are placed into one of 2 main groups for how they obtain their
energy.
Each main group also has 2 subgroups.
• A – Autotrophs – produce their own food
o A1 – phototrophic autotrophs – use sun (light) to produce
their food
o A2 – chemotrophic autotrophs – intake inorganic
chemicals to produce their food
• B – Heterotrophs – need to intake food
o B1 – phototrophic heterotrophs – use photosynthesis and
inorganic molecules
o B2 – chemotrophic heterotrophs – take in organic
materials for food
5 – Producing Energy – Respiration
There are 2 ways for a bacteria (or any cell) to produce energy
• A – Respiration – aerobic – requires O2
• B – Fermentation – anaerobic – no O2
There are 3 groups of bacteria (according to their respiration style)
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Obligate aerobics – require O2 to live
Obligate anaerobics – cannot have O2, (O2 will kill them)
Faculative anaerobics – don’t need O2 but are not harmed by it.
Reproduction in Bacteria
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Bacteria reproduce mostly asexually
o Binary fission – one cell splits into 2 identical cells
o All offspring are identical
There is a “kind” of form of sexual reproduction
o Conjugation – where there is an exchange of genetic material between 2
bacteria through a protein bridge
This allows for some genetic diversity, and therefore bacteria can evolve
or adapt to new environments
During extreme conditions, some bacteria will go into spore formation.
o During spore formation, an endospore is formed
The endospore has a thicker cell wall that encases the DNA and some of
the cytoplasm
The endospore can remain dormant for months
Ex) Clostridium difficile (C. difficile or C. diff)
• The endospores cannot be killed directly with bleach and remain
dormant for about 6 months
• Hospitals with a C. diff problem have outbreaks every 6 months