Topic 3 - Kingdom Monera

-also known as bacteria

Structure
- unicellular, but some form colonies or filaments
-prokaryotes (no membrane-bound nucleus or cellular organelles)

Size
1-10 micrometers

Reproduction
- asexual:  binary fission, in good conditions a bacteria can copy itself every 20 minutes!

Image from :  http://web1.stmaryssen-h.schools.nsw.edu.au/SMSHS/ricks%20sites/Biology%20web%20site/HSC_9_4%20search%20for%20health/Chapter10_overview/disease_causing_organisms_files/reproductionofbacteria.htm 

- sexual:  conjugation

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Image from:  http://commons.wikimedia.org/wiki/File:Bacterial_Conjugation_en.png

Occurrence
EVERYWHERE!  Can be found in soil, air, water, even extreme environments.
Why?
1.  small and simple
2.  rapid reproduction (adapt quickly to changes)
3.  less specialized (adapt quickly to changes)
4.  slimy, thick capsule and cell wall (great protection)
5.  can use "poisons" (or things humans consider poisonous!)
6.  can form endospores (survive freezing, boiling, drying, radiation and chemicals)

Nutrition
1.  Autotrophs (self-feeders)
a) photoautotrophs can produce food for themselves through photosynthesis.  So they use the energy from the sun to produce sugar.
b) chemoautotrophs can produce food for themselves through chemosynthesis.  So they use chemical energy from the oxidation of inorganic molecules (like hydrogen sulfide) to produce sugar.

2.  Heterotrophs (fed by others)
a) consumers (fogyasztók)
b) parasites - pathogens (kórokozók), they cause disease (eg. Lyme's disease, tuberculosis, salmonella, tetanus)
c) saprotrophs - feed on dead things, also called decomposers (lots found in soil and oceans)
d) mutualists/symbionts - live together with another organism and each provides a "service" to the other (eg. E. coli and humans, cyanobacteria and fungi=lichens)


Respiration
1.  Aerobe:  an organism which requires oxygen.  Releases the energy found in food in a process called cellular respiration
2.  Anaerobe:  an organism which doesn't need oxygen.  Releases the energy found in food in a process called fermentation. They are commonly found in soils (facultative), lake sediments (obligate) and are used in sewage treatment plants to digest sewage sludge.

Classification
1.  Archea (ősbaktériumok): often found in extreme habitats
- newer classification now places the Archea as a separate group from the bacteria, because they seem to have a different evolutionary history.  For a long time they were considered part of the bacteria, but no longer!  Physically they resemble bacteria, but their genes seem to be more closely related to eukaryotes (still they don't have a nucleus) 

2.  Eubacteria (valodi bakteriumok)
- classified by shapes: cocci (spheres), bacilli (rods), spirilli (spirals)

 

 - this group contains the bacteria that cause most human bacterial diseases.  Most can be either prevented by vaccines, or treated with anti-biotics

-most bacteria DON'T cause disease!!

E. coli

 Bacterial colonies on a plate

3.  Cyanobacteria (aka blue-green algae, but they aren't algae!) (kékalgák, kékmoszatok)

-autotrophs with bluish-green pigments in cytoplasm

-live in ponds, streams, lakes, moist land

-long chains (filaments) - slimy

-can cause "algal blooms"

Importance

-huge diversity:  producers (make oxygen), consumers, decomposers (keep the cycle of life flowing)

-biotechnology:  fermentation, antibiotics, hormones, insect pest control, sewage/chemical breakdown, genetic research and engineering

Extra credit project:  Make your own yogurt.  See the extra credits tab.