1. What is your “take away” from Mr. Chesser’s talk yesterday?
Catalyst
What is your “take away” from Mr. Chesser’s talk yesterday?

2. Fungal colonies vs. bacterial colonies

3. Post lab:
Why do we need to swab our control dish with distilled water?
Was the control effective? Why/ why not?
Some quadrants have Zero growth in them. Explain why this is.
Why did the growth of the microorganisms vary with location?
Are bacteria ubiquitous? How do you know?

4. Catalyst:
List down the following factors in the bacterial culture investigation:
Independent variable
Dependent Variable
Control
Constants

5. Species, kingdom, domain, family, order, genus, phylum
DO YOUR BEST:Arrange the following from the largest to the smallest taxon( group)
Species, kingdom, domain, family, order, genus, phylum

6. Taxa/levels of classification

8. Domains of Life
Prokaryotes

9. Domain Prokarya
An Overview

10. Prokaryotes Vs. eukaryotes
Characteristic
Eukaryote
Prokaryote
Genetic Material
Location
Contained in membrane bound nucleus
Free in cytoplasm, attached to a structure called mesosome located in the cell membrane
Form
Multiple chromosomes
Single circular piece of DNA
Replication
Mitosis & meiosis
Binary fission
Extrachromosomal DNA
In mitochondria
Plasmids, small circular taining accessory pieces of DNA containing accessory info, maybe present in the cytoplasm

11. Prokaryote vs. Eukaryote
Characteristics
Eukaryote
Prokaryote
Protein Synthesis
Site
Rough ER
No ER, ribosomes are free in the cytoplasm or attached to the cell membrane
Energy site
Within membrane- bound mitochondria
ETC is located in the cell membrane; no mitochondria
Lysosomes
Contain hydrolytic enzymes
Not present
Cell envelope
Plasma membrane
Cell Wall
Lipoprotein membrane;regulates transport
Usually absent except for fungi, which contain chitin in the cell wall
Lipoprotein membrane; regulates transport
Present; imparts rigidity; various types ( gram negative/gram positive)

12. Archaebacteria
Detection of pathogens,
amplify/make copies of DNA

13. Prokaryotes include: Archaebacteria/ archaea “ Extremophiles” Ex:
Methanogens – intestines, produce methane from hydrogen
Halophiles – salt (Utah’s great Salt Lake)
Thermophiles – heat tolerance (Hot Springs, deep sea hydrothermal vents)
May have been on Earth for 3.5 billion years
Eubacteria – all other bacteria

15. Archaebacteria Salt crust is colored red by dense colonies
of halophilic archaebacteria. Sierra Nevada
Halophilic bacteria surviving in salt crystals.
Owens Valley, California

16. Characterizing Eubacteria
Bacteria can be characterized by shape

17. Characterizing Bacteria
A. Oxygen requirements
a. Aerobic Bacteria require oxygen to support reproduction
ex.Esherichia coli
B. Anaerobic bacteria reproduce in the absence of oxygen
Listeria
Clostridium botulinum

18. Characterizing Bacteria
Facultative bacteria reproduce either in the presence or in the absence of oxygen.
Salmonella
Staphylococcus aureus

19. Characterizing Bacteria:

20. Gram Positive Vs. Gram Negative Bacteria

21. Characterizing Bacteria
Bacteria secrete a covering for themselves - cell wall
Do not contain cellulose like plant cell walls
Mostly made of peptidoglycan (polypeptides bonded to modified sugars)
the amount & location of the peptidoglycan are different in the two possible types of cell walls, depending on the species of bacterium

22. Characterizing Bacteria
Some antibiotics, like penicillin, inhibit the formation of the chemical cross linkages needed to make peptidoglycan.
These antibiotics don’t outright kill the bacteria, but just stop them from being able to make more cell wall so they can grow.
That’s why antibiotics must typically be taken for 7-10 days until the bacteria die (unable to grow)
If a person stops taking the antibiotic sooner, any living bacteria could start making peptidoglycan, grow, and reproduce.

23. Characterizing Bacteria
Dr. Hans Christian Gram, a Danish physician, invented a staining process to tell the two types of bacteria apart, and in his honor, this process is called Gram stain.

24. Gram Stain
the amount of peptidoglycan in the cell walls of the bacteria determine how those bacteria absorb the dyes with which they are stained
bacterial cells can be Gram+ or Gram -.
E.Coli and Strep

25. Gram Stain
Gram+ bacteria have simpler cell walls with lots of peptidoglycan, and stain a dark purple color.
Anthrax

26. Gram Stain
Gram- bacteria have more complex cell walls with less peptidoglycan, thus absorb less of the purple dye used and stain a pinkish color instead
Pseudomonus aerugenosa
E.coli

27. Gram Stain
Gram negative bacteria often incorporate toxic chemicals (called endotoxin) into their cell walls, thus tend to cause worse reactions in our bodies.
antibiotics like penicillin are less effective against gram negative bacteria.
Ampicillin was developed to treat gram negative bacteria

28. Gram Stain Gram staining involves a four-part process, which includes:
crystal violet, the primary stain
iodine, the mordant
a decolorizer made of acetone and alcohol
safranin, the counterstain