1. Guide to infectious Pathogens (“Disease Causers”)
Viruses: Bacteria: Protists/Fungi:
(not alive) (Prokaryotes) (Eukaryotes)
protein coat cell membrane cell membrane
DNA or RNA maybe cell wall DNA in nucleus
that’s all! DNA -no nucleus chromosomes ribosomes organelles
Very small ~ 5 mm ~ 100 mm
no cure antibiotics invented
(vaccines) cure antibiotics
Cell membrane
DNA in nucleus
Chromosomes
Organelles

2. Guide to the Pathogens (= “Disease Causers”)
Viruses: Bacteria: Protists/Fungi:
(not alive) (Prokaryotes) (Eukaryotes)
HIV/AIDS Tuberculosis Malaria
“Flu” Plague Amoebic
Colds Lyme Disease Dysentery
Ebola Leprosy
Smallpox Cholera

3. Prokaryotes: 2 kingdoms, Eubacteria and Archeabacteria.
No nucleus
No Organelles
Small
Evolved ~ 3.5 million years ago
Some require oxygen (O2) some do not

4. More about the Eubacteria:
Cell Walls – two types
Gram stain (+) or (-)
Gram-negative do not respond to antibiotics
Shapes: spherical (“cocci”), spiral, rod shaped

5. More about the Eubacteria:
Reproduction: DNA duplicates, cell divides
Nutrition: Autotrophs (make own food by photosynthesis or chemosynthesis)
Heterotrophs (food made by others)
Roles: decomposers, N2-fixers, yoghurt, cheese, etc.
N=N

6. More about the Eubacteria:
Food contamination: salmonella & botulism!
Sanitation, heat, cold, vaccination and antibiotics our best defenses
(blue-green bread mold makes penicillin, an antibiotic.)

7. More about viruses: Not alive. Not cells
Reproduce by taking over a cell’s nucleus and ribosomes
Vaccines won’t work if virus mutates quickly
Antibiotics don’t work at all against viruses

8. 1. Virus lands on cell membrane
How do viruses work?
1. Virus lands on cell membrane

9. 2. Virus injects its DNA or RNA:
How do viruses work?
2. Virus injects its DNA or RNA:

10. 3. Cell’s enzymes and ribosomes make new virus parts
How do viruses work?
3. Cell’s enzymes and ribosomes make new virus parts

11. 4. New virus parts assemble themselves.
How do viruses work?
4. New virus parts assemble themselves.

12. 5. Cell fills with new viruses and then bursts:
How do viruses work?
5. Cell fills with new viruses and then bursts:

13. Eukaryotes ( 4 kingdoms: Animals, Plants, Fungi, Protists.)
Have nuclei
Have many organelles
Big
Evolved ~1 billion years ago
Require O2
Cell membrane
DNA in nucleus
Chromosomes
Organelles

14. Archae- Bacteria Eu- bacteria
Fungi =
decomposers
Plants =
Photo-
synthesizers
Animals
Eukaryotes = cells with nuclei
Protists =
one cell
Archae-
Bacteria
environments)
(extreme
Eu-
bacteria
Prokaryotes = no nuclei