1. Viruses, Bacteria, Archaea, Protists, Fungi
Classification
Viruses, Bacteria, Archaea, Protists, Fungi

2. Bacteria

3. Eubacteria Structure Unicellular, prokaryotic organisms
Large circular chromosome
Cell walls (peptidoglycan)
Cell wall prevents osmotic (water) rupture.

4. Prokaryotes are the foundation of life on earth
Decompose dead organisms
Decomposers, saprobes, saprophytes
Put good nitrogen into air
Live in our digestive system and are also used in the food industry
Cheese, yogurt, etc
Used to decompose waste in sewage
Disesase causing bacteria – Usually produce toxins. Ex- bacteria that causes botulism (paralyzes nerve cells)

5. Some Prokaryotes Cause Disease
Bacterial Examples: cholera, diphtheria, leprosy, Lyme disease, meningitis, the plague, pneumonia, syphilis, gonorrhea; tetanus, tuberculosis, strep throat. See book for more.
Antibiotics are the most effective means of fighting bacterial infections
Penicillin breaks down cell wall and allows rupture
**No known Archaea cause disease

6. Archaea

7. Major Groups of Archaea
Extremophiles-3 types
Methanogens: are poisoned by oxygen
use CO2 as the electron acceptor in respiration
produce methane as a waste product
Halophiles- lives in very saline places
Thermophiles (aka hyperthermophiles)

8. Archaeabacteria vs eubacteria
Used to be grouped with bacteria and called Monerans
Now believed eukaryotes “split” from archaeal line of descent
Differences between Arch and Bac:
Archaea have “unusual” diverse lipids in membrane that allow them to live under extreme conditions
Cell walls composed of polysacc and some only are entirely protein. **A few recently discovered have no wall (not on test, just FYI)
Similarities between Arch and Euk:
Arch and Euk share some of the same rRNA sequences and ribosomal proteins
Similar tRNA
Some Archaea have introns; bacteria do not

9. The Origin of the Eukaryotic Cell
Eukaryotic cells arose through a combination of 2 processes:
Membrane Infolding:
Produced all the membrane-bound organelles except the mitochondrion and the chloroplasts.
Endosymbiosis:
Mitochondria and chloroplasts once prokaryotic cells that were ingested or absorbed by other cells.

10. Protista

11. Kingdom Protista Very diverse group of organisms Most are unicellular
Currently being phylogenetically reclassified based on common DNA sequences, proteins, and therefore common ancestors
Most are unicellular
The most elaborate cells of all the kingdoms

12. Kingdom Protista Most are aerobic & use mitochondria for respiration
Some are autotrophs, some are heterotrophs
3 types: ingestive, absorptive, photosynthetic.

13. Amoeba- moves and ingests using pseudopodia

14. Ciliates
Paramecium- has both a macro and micro nucleus, so it has a “reserve” copy of genome. Macro regulates metabolism and micro is used in conjugation.

15. Flagellates
Euglena- unique flagellate. Both autotrophic and heterotrophic

16. Diatoms
Contain silica “shells”- forms diatomaceous earth

17. Volvox- single cells, but colonial

18. Red Tide

19. More Plant-Like Protists
P. Phaeophyta – the brown algae
include the largest seaweeds, the kelps (**multicellular)
P. Rhodophyta – the red algae
include the red seaweeds, some encrusted and common in coral reefs

20. Fungi

22. What is a fungus? Most are multicellular Cell walls made of chitin.
Heterotrophic
Nonphotosynthetic
Digest food outside bodies (using enzymes) and absorb it
Some live off of dead organic matter
Decomposers

23. Structure and Function of Multicellular Fungi
Composed of tiny filaments called hyphae
Hyphae are long strings of cells. Mass called mycelium. Some species can grow a km of hyphae/day!
Can reproduce asexually by releasing haploid spores
Unicellular fungi-yeast
Multicellular ex: mushrooms, molds

24. Ecological Impacts of Fungi
Decomposers! Important nutrient recyclers
Some are pathogens, such as ringworm and athletes foot.Plant pathogens--Dutch elm disease, Chestnut blight
• Some produce deadly toxins-ex-some species of mushrooms
• We use them for their antibiotics-penicillium. Produce enzymes that rupture bacterial cell walls