The Microbial W orld

1. The Microbial World Chapter 5 http://www.youtube.com/watch?v=1TmHlcMDIOQ

2. Microorganisms • All three domains have microogranism representation • What are those three domains? • Without microorganisms there would be no life on earth.

3. Domain: Bacteria

4. Domain: Archaea

5. Domain: Eukaryota

6. Primary producers • Microorganisms are the most important primary producers • Directly or indirectly feed most marine animals

7. Prokaryotes • Small • Structurally simple • Oldest life forms on earth • Carry out nearly all the chemical processes more complex organisms do • Some unique processes to prokaryotes • Most chemical processes evolved first in prokaryotes

8. Prokaryote Structure • Cell wall • Lack a nucleus • Lack membrane bound organelles • Differ from Eukaryotes in • Shape of DNA – circular shape • Size of ribosomes

9. Prokaryote

10. Two Prokaryotic Domains • Bacteria • Archaea • Even these two prokaryotic domains have important differences • Bacteria and Archaea are as different from each other as they are from humans! Woah! • Discovery ed

11. Bacteria • Structurally simple • Classified as prokaryotes • Evolved a range of metabolic abilities • Abundant in all parts of the ocean • Shapes • Spheres, rods, sprials, rings -Ridged cell wall with slimy covering (attach to surfaces)

12. Size of bacteria • Smaller than unicellular eukaryotes. • Exception- bacteria found in sediment off southwest Africa- large enough to be seen with the naked eye

13. Where do they live • Can grow to extremely high numbers in favorable conditions • Detritus (particles of dead organic matter) • Decay bacteria – break down waste products and dead organic matter • Releases nutrients into the environment

14. Why are they important • As we know bacteria are very abundant – Marine environment offers some new discoveries • Make up large part of the organic material that feeds bottom-dwellers • Important in dredging oil and other toxic pollutants • Bad side- spoil fish and shellfish catches

15. http://www.youtube.com/watch?v=mYG5vmad1mk

16. Cyanobacteria • Blue-green algae • Photosynthetic • Pigments chlorophyll • Phycocyanin (Blue) • Phycoerythrin (Red) • Visible color depends on the relative amounts of the two pigments

17. Cyanobacteria • Where among the first photosynthetic organisms on earth. • Accumulation of oxygen in our atmosphere • Stromatolites- Massive calcareous mounds formed by cyanobacteria. • Date back to 3 million years • http://www.youtube.com/watch?v=uzwvjOSS2Pc

18. Cyanobacteria • Endolithic- burrow into calcareous rocks and coral skeletons • Red tides- caused by a planktonic form that blooms • Some can cause skin rashes on divers and swimmers • Epiphytes- on algae and plants • Endophytes- live inside algae

19. Bathroom Break • 

20. Archaea • Some times called archaebacteria • Simple • Primitive life • Important role in the early evolution of life

21. Structure • Small • Spherical, spiral, rod shaped • Despite being prokaryotic, there is evidence that archaea are more closely related to eukaryotes than bacteria

22. Where do they live? • Some groups were discovered recently • Extreme environments • Hot sulfur springs, saline lakes, highly acidic or alkaline environments • Extremophiles “lovers of extreme environments” • Also found in extreme marine environments • They are not restricted to extreme environments • Common in the water column and other marine environments • http://www.youtube.com/watch?v=D69hGvCsWgA

23. Exit Ticket • 1)Blue green algae are known as • a) Archaea b) Extremophiles c) Cyanobacteria d) Cilliates • 2) Which of the following is not a domain a) Archaea b) Bacteria c) Eukaryota d) Fungi • 3) Bacteria and Archaea are very closely related • a) True b) False • 4) Stramenopiles are made up of • a)Cyanobacteria b) Diatoms c) Dinoflagellates d) Amebas • 5) Bacteria are prokaryotes • a) True b) False