1. KEY CONCEPT Bacteria and archaea are both single-celled prokaryotes.

2. Prokaryotes are widespread on Earth.
Prokaryotes can be grouped by their need for oxygen.
obligate anaerobes are poisoned by oxygen
obligate aerobes need oxygen
facultative aerobes can live with or without oxygen

3. Modes of Nutrition Saprobes – feed on dead organic matter
Parasites – feed on a host cell
Photoautotroph – use sunlight to make food
Chemoautotroph – oxidize inorganic matter such as iron or sulfur to make food

4. Bacteria commonly come in three forms. rod-shaped, called bacilli
Bacteria and archaea are structurally similar but have different molecular characteristics.
Bacteria commonly come in three forms.
rod-shaped, called bacilli
spiral, called spirilla or spirochetes
spherical, called cocci
Lactobacilli: rod-shaped
Spirochaeta: spiral
Enterococci: spherical
Archaea have many shapes.

8. Clicker Question!
What shape and grouping describes the bacteria pointed out below?
A: Staphalacoccus
B: Streptobacillus
C: Diplococcus

9. Staphylococcus Bacterial

10. Streptococcus Causes Strep Throat

11. Bacillus - E. coli

12. Streptobacilli

13. Spirillum

14. Leptospira

15. Clicker Question! 1. _________ 2. _________ 3. _________ 4. _________
5. _________
6. _________
A. Staphylococcus
B. Coccus
C. Spirillum
D. Bacillus
E. Streptococcus
F. Diplococcus

16. Bacteria

17. Archaebacteria

18. Methanogens Break down cellulose in a cow’s stomach
Produce marsh (methane) gas

19. Extreme Halophiles Live in very salty water
Use salt to generate ATP (energy)
Dead Sea, Great Salt Lake inhabitants

20. Thermoacidophiles or Thermophiles
Live in extremely hot environments
Found in volcanic vents, hot springs, cracks on ocean floor that leak acid

21. Have a membrane bound nucleus and organelles:
Clicker Question!
Have a membrane bound nucleus and organelles:
A: Prokaryotes
B: Eukaryotes
C: Nokaryotes

22. Bacteria vs Archaebacteria

23. Bacteria and archaea have similar structures. plasmid flagellum pili
cell wall
chromosome
plasma membrance
This diagram shows the typical structure of a prokaryote. Archaea and bacteria look very similar, although they have important molecular differences.

24. Bacteria and archaea have molecular differences.
The amount of peptidoglycan within the cell wall can differ between bacteria
GRAM NEGATIVE
GRAM POSITIVE
Archaea have different lipids entirely (cell walls lack peptidoglycan)

25. Gram staining identifies bacteria. stains polymer peptidoglycan
gram-positive stains purple, more peptidoglycan
gram-negative stains pink, less peptidoglycan
Gram-negative bacteria have a thin layer of peptidoglycan and stain red.
Gram-positive bacteria have a thicker peptidoglycan layer and stain purple.

26. Bacteria have various strategies for survival.
Prokaryotes exchange genes during conjugation.
conjugation bridge
TEM; magnification 6000x
Bacteria may survive by forming endospores.

27. Pili in Conjugation
Hairlike structures that help them attach to surfaces and allow for transfer of genetic material between two bacteria

28. Sticky Bacterial Capsule
Prevents drying out, allows it to attach to other surfaces, prevents it from being engulfed, & shelters it from antibiotics

30. Flagella Bacteria that are motile have appendages called flagella
A bacteria can have one or many flagella

31. Monotrichous
Lophotrichous
Amphitrichous
Peritrichous

32. Clicker Question!
What domain can be found in harsh environments like: Undersea volcanic vents, acidic hot springs, salty water?
A: Bacteria
B: Archaea
C: Eukarea

33. Clicker Question!
Some bacteria gain energy from the sun (cyanobacteria), but the rest have to gain energy by consuming other organisms. These are called: A. Homotrophs B. Heteroeaters C. Heterotrophs D. Homoconsumers

34. Clicker Question! What structure does this bacterium use for motility?
A: Flagella
B: Cilia
C: Pili

35. Clicker Question!
Which type of bacteria is susceptible to antibiotics? A: Gram Positive (Dark Purple) B: Gram Negative (Light Pink)

36. Clicker Question!
What kind of reproduction is depicted in the photo below?
A: Asexual
B: Conjugation
C: Binary fission

37. KEY CONCEPT Prokaryotes perform important functions for organisms and ecosystems.

38. Prokaryotes provide nutrients to humans and other animals.
Prokaryotes live in digestive systems of animals.
make vitamins
break down food
fill niches

39. Bacteria help ferment many foods.
yogurt, cheese
pickles, sauerkraut
soy sauce, vinegar

40. Bacteria make Medicine
Vitamins
Antibiotics:
Streptomycin
Bacitracin
Tetracycline
Vancomycin

41. Prokaryotes play important roles in ecosystems.
Prokaryotes have many functions in ecosystems.
photosynthesize
recycle carbon, nitrogen, hydrogen, sulfur
fix nitrogen

42. Bioremediation uses prokaryotes to break down pollutants.
oil spills
biodegradable materials

43. KEY CONCEPT Understanding bacteria is necessary to prevent and treat disease.

44. Some bacteria cause disease.
Bacteria cause disease by invading tissues or making toxins.
A toxin is a poison released by an organism.

45. Normally harmless bacteria can become destructive.
may colonize new tissues

46. Normally harmless bacteria can become destructive.
immune system may be lowered

47. Pathogens
STD: Syphilis, gonorrhea, Chlamydia Respiratory: Strep throat, pneumonia, whooping cough, tuberculosis, anthrax Skin: Acne, boils Digestive: Gastroenteritis, food poisoning, cholera Nervous: Botulism, tetanus, bacterial meningitis Other: Lyme disease, typhoid fever

48. Antibiotics are used to fight bacterial disease.
Antibiotics may stop bacterial cell wall formation.
Antibiotics do not work on viruses.
Prevention is best method to fight bacterial disease.

49. Bacteria can evolve resistance to antibiotics.
Bacteria are gaining resistance to antibiotics.
A bacterium carries genes for antibiotic resistance on a plasmid.
A copy of the plasmid is transferred through conjugation.
Resistance is quickly spread through many bacteria.
overuse
underuse
misuse
Antibiotics must be used properly.