Transcript Taking a Closer Look at Kingdom Eubacteria, Archaea and (if we

Taking a Closer Look at Kingdom
Eubacteria, Archaea and Viruses
Objectives:
1. Compare and contrast Eubacteria, Archaea and
Viruses
2. Explain why viruses are not part of any of the 6
kingdoms
3. Discuss some benefits and negatives of bacteria
Microscopic Organisms
• Microscopic bacteria and viruses are the cause of
many diseases.
– Respiratory infections
– Flu
– Plague
• They also play an important role in the ecosystem.
– Recycling nutrients (convert nitrogen into a form plants can
use)
– Production (Cheese, Yogurt, Vitamin K and B12)
– Sewage Treatment
– Digestion
– Decomposer
– Produce antibiotics (to compete with other bacteria)
Prokaryotes
• Domain Eubacteria and Archaea are singlecelled and lack membrane bound organelles.
• Extremely small
• Dominate forms of life because they live in
every habitat
– Inside and on other organisms (100 trillion+ on
your body!)
– In water and soil (even deep within the Earth)
– In boiling hot springs
– In acid and even on and in ice!!! (Totally extreme)
Yellowstone National Park
Cell Shapes
• Both Archaea and
Eubacteria can be
classified based on
their shape..
– Bacillus (rod shaped)
E.coli
– Coccus (round)
Streptococcus
– Spirillum (spiral)
Spirillum minus
Eubacteria
• Consist of a cell wall ( composed of
__________________which makes the cell
strong) and a plasma membrane surrounding
the cytoplasm.
• Chromosome is
___________________________.
• Also may contain _______________(small
loop of extra DNA with a few genes)
• Contains ribosomes which make
___________________
• Have flagellum for ______________________
• ____________help cell attach to surfaces
Metabolism
• Autotrophic bacteria: Make their own food
– Cyanobacteria or blue-green algae, blue-green bacteria
– Use energy from the sun (photosynthesis)
• Heterotrophic bacteria: Get nutrients from other
organisms
– Heterotrophic bacteria include parasitic types
– E.Coli - The products of their metabolism may be toxic to
animals
Reproduction - Asexually
• Reproduce asexually by binary
fission.
• Similar to mitosis
– DNA replicates
– Cell elongates
– Cell splits apart
• Also may be subject to mutations.
– Bacteria reproduce rapidly so
mutations occur more frequently
• Bacteria can gain new DNA
through infection by a virus or
conjugation.
• Conjugation: Form of
sexual-like
reproduction (two cells
join and exchange
genetic info.)
Archaea
• Similar to bacteria in some ways…
– Have a cell wall, but lack peptidoglycan
– Different genetic information
– Can occupy much more extreme
environments (acidic, boiling)
Subgroups
Methanogens: Live in low oxygen environments
- Swamps, Sewage lagoons, Digestive tracts
- Convert methane gas into energy
Halophiles: Salt lovers that live in environments that
are very salty
- Dead Sea, Foods preserved by salt
- Convert food molecules into energy
Extreme Thermophiles: Live in very hot
environments (70 - 95ºC is optimal for growth)
Psychrophiles: Live in Antarctic and Artic
environments
(-10 to – 20 ºC is optimal for growth)
Viruses
• Non–living infectious particles that
pass from cell to cell and organism to
organism.
• They infect a cell and take over control
forcing or tricking the cell into making
copies of the virus.
Your Turn
• Complete the hand out on ‘Comparing and
Contrasting the structure and function of
Prokaryotes, Eukaryotes and Viruses.
Plenary
1. Compare and contrast Archaea and
Eubacteria (how are they similar and different)
2. How do bacteria reproduce?
3. How are bacteria classified?
4. How are bacteria harmful/helpful?
5. Why are viruses considered to be non-living?
6. Compare and contrast virus and bacteria
reproduction.
Additional Questions
• H/W
• Page 344 #1, 2, 4, 6, 7
• Make a table to summarize the benefits of
bacteria and the harmful effects of bacteria