3. Viruses Most contain: Nucleic acid Protein coat
Membrane surrounding protein coat

4. replication

6. “Viruses, can replicate themselves, despite their paltry genetic instructions, by hijacking other forms of life. They… inject their genes and proteins into a host cell, which they [manipulate] into producing new copies of the virus. One virus might go into a cell, and within a day, a thousand viruses [come] out.”
– Carl Zimmer “A Planet of Viruses”

7. Newly released phage may infect another cell
Attaches to cell
Phage DNA
Newly released phage may infect another cell
The cell lyses, releasing phages
The phage injects its DNA 1 2 4 3 5 6
Bacterial chromosome
Many cell divisions
Environmental stress
Prophage
Lysogenic cycle OR
The phage DNA circularizes
Lytic cycle
Phage DNA inserts into the bacterial chromosome by recombination
New phage DNA and proteins are synthesized
Phages assemble
The lysogenic bacterium replicates normally,
copying the prophage at each cell division

8. Ebola Filament structure – more surface area to infect many cells
Spreads through direct contact with infected bodily fluids or tissues
The fluids of a person infected with Ebola must enter another person’s mouth, eyes or other opening to skin (ie. Cut, scrap etc.)

9. Ebola Infects white blood cells first (the body’s immune system)
Then infects the other cells
Recognizes the cells by the extracellular matrix

10. More than Domains and Kingdoms
Mnemonic:
Did King Phillip Cry Out “For Goodness Sakes!”?

11. Brief History of Taxonomy
Carl Woese – 1970’s to now
3 Domains, 6 kingdoms
Bacteria
Monera
Archaea
Plantaea
Animalia
Protista
Fungi

12. Microbial life: Prokaryotes and Protists
Prokaryotes consist of Archaea and Bacteria
Recall:

13. Prokaryote Cells Vs. Eukaryote Cells
All are single celled organisms
found in Domains Archaea and Bacteria
Prokaryotic cells are smaller and simpler in structure

14. Prokaryote Cells Vs. Eukaryote Cells
In a prokaryotic cell,
the DNA is coiled into a region called the nucleoid (nucleus-like) and
no membrane surrounds the DNA.

15. Microbial life: Prokaryotes and Protists
Protists are a Kingdom within Eukarya
Protists are mostly single celled, some colonial or multicellular
More complex than the Archaea and Bacteria
Protista
Fungi
Plantea
Animalia
Eukarya

16. Focus on Prokaryotes
Archaea – is the domain of life typically characterized by organisms that live in extreme environments
Bacteria – the domain of life that has a huge diversity of organisms that are often beneficial to multicellular organisms like humans

18. Cell Wall – not just in plants…
Nearly all prokaryotes have a cell wall.
provide physical protection and
prevent the cell from bursting in a hypotonic environment.

19. Gram Stain
When stained with Gram stain, cell walls of bacteria are either
gram-positive - with simpler cell walls
gram-negative - more complex and more likely to cause disease.

20. Capsule a sticky layer of protein.
enables prokaryotes to adhere to their substrate or to other individuals in a colony and
shields pathogenic prokaryotes from attacks by their host’s immune system.
Capsule
Tonsil cell
Bacterium

21. What is pathogenic?
A pathogen is an agent, like a virus, bacteria, or fungus, that can cause disease
Not all viruses, bacteria, or fungi cause disease.

22. Shapes Coccus – (Cocci) Bacillus – (Bacilli) Spirochetes (long)
a spherical shape
Bacillus – (Bacilli)
rod shaped
Spirochetes (long)
Spirilla (short)
corkscrew shaped

23. Movement Flagella propels a cell by an undulating, whiplike motion
Cilia work more like the oars of a boat, all working together
Made of microtubules from the cytoskeleton

26. Other Projections
Hairlike projections called fimbriae (fimbria) enable prokaryotes to
stick to a surface or each other or
latch onto the host cells they colonize.
Flagella
Fimbriae

27. Quick Replication Prokaryote population growth
occurs by binary fission
can rapidly produce a new generation within hours, sometimes multiple generations in an hour

28. Scientists study bacteria in lab with agar plates

31. Swapping Genetic information
The purpose of genetic information is to provide the instructions to make proteins
Bacterial DNA is part of the Nucleoid
Plasmids are small round sections of DNA floating in the cell

33. Swapping Genetic information
Take a minute to share with a partner what you learned from the video clip.

34. Bacterial conjugation
the transfer of genetic material (plasmid) between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells

35. How do humans get energy? How do plants get energy?
Eating other organisms
Sunlight and CO2

36. How do prokaryotes get their energy?
Two sources of energy are used.
Phototrophs capture energy from sunlight.
Chemotrophs harness the energy stored in chemicals.

37. How do prokaryotes get their carbon?
Two sources of carbon are used by prokaryotes.
Autotrophs obtain carbon atoms from carbon dioxide (CO2).
Heterotrophs obtain their carbon atoms from the organic compounds present in other organisms.

38. Combine terms for the source of carbon and source for energy
Energy Source
Sun
Chemicals
Organic Compounds
photoheterotroph
chemoheterotroph
Carbon Source
CO2
photoautotroph
chemoautotroph

39. Combine terms for the source of carbon and source for energy
Photoautotrophs harness sunlight for energy and use CO2 for carbon.
Photoheterotrophs obtain energy from sunlight but get their carbon atoms from organic sources.

40. Combine terms for the source of carbon and source for energy
Chemoautotrophs harvest energy from inorganic chemicals and use carbon from CO2 to make organic molecules.
Chemoheterotrophs acquire energy and carbon from organic molecules.

41. Cyanobacteria Photoautotrophic bacteria Utilize photosynthesis
Often called ‘blue green algae’

42. Bacteria toxins
Exotoxin – a poisonous toxin that is secreted by a bacteria (+)
Endotoxin – a poisonous toxin that is only released when the cell dies (-)

43. Bacteria Protection Cell wall, capsule, toxins
Endospore – formed when environmental conditions are poor for replication
Able to reproduce when conditions improve

44. Archaea Recall – they are often found in extreme environments
Thermophile – thrives in high temperatures
Halophile – lives in a highly saline (salty) environment