1.
4 staining procedures?: SImple
Differential
Special
Negative
2.
avg size of most bact?: 1-3 microns
3.
bacterial endospores:: a form of cellular differentiation (NOT reproductive and not spores) formed within vegetative cells, survive nutrient limitation, highly resistant to drying
4.
Bacterial intracellular storage materials:: inclusion bodies; storage units for bact; glycogen, poly-beta-hydroxybutyric acid; inorganic polyphosphate (metachromatic granules)- these are not membrane bound
5.
Basic Shapes of bacteria: 1. Coccus - divide in 1 or 2 planes or random; spherical
2. Rod (bacillus)- divide in one plane
3. Helical - spiral bacteria
4. Square - only in extremes
6.
Basis for gram staining?: differentiating bacterial species into two large groups (Gram-positive and Gram-negative) based on the chemical, primarily the presence of high levels of peptidoglycan, and physical properties of their cell walls.
It yields results much more quickly than culture,
7.
brightfield:: light microscopy, fixed preps
8.
cell wall deficient forms:: Mycoplasma - take on many different shapes ( bc no cell wall)
pleiomorphic - many shapes
9.
Characteristics of Viruses: neither prok or euk
not cells
they are nucleic acid (DNA or RNA)
may be enclosed in viral envelope
need to infect living to replicate.
10.
chemical composition of capsule: polysaccharides, polypeptides
11.
Chemical composition of cell wall: Peptidoglycan (murein) - repeating disaccharide polymer of N-acetyl glucosamine (NAG) and N-acetylmuramic acid (NAM) w tetrapeptide chain and peptide crosslinking
12.
Colonial Characteristics?: size
shape
elevation
margin (smooth, rough)
consistency (thick, creamy)
light reflecting-light transmitting characteristics
pigmentation
13.
components of cell envelope: cell membrane, cell wall and glycocalyx (capsule)
14.
darkfield:: background dark, specimen is light
15.
Define a colony: visible mass of cells derived from a single cell, it is a pure culture.
16.
Describe the Gram staining procedure: 1. crystal violet gets stuck to wall
2. mordant used to fix dye iodine
3. decolorize to wash away dye (gram + retains dye bc cell wall much thicker)
4. counterstain - safranin used to add red to Gram(-) cells so they can be seen.
17.
Differential Staining:: gram stain (most impt) - one group looks one way and the other looks another way
18.
diplo:: 2 cells pairs
19.
electron microscpy:: highest level of magnification
scanning and transmission. use e- instead of photons of light.
20.
Explain how Animal methods are used in ID'ing procedures: culture medium for certain MO's
helps in determining effects of antisera, drugs, etc
source of antisera, cells, blood, etc
ID of MO's or their products
follow pathogenesis of infectious disease
21.
Explain how biochemical methods are used in ID'ing procedures: needed for further differentiation and identification - fermentation of different sugars and enzymatic activity
22.
Explain how Serological methods are used in ID'ing procedures: test is mainly for confirmation of ID. by providing a brief description of the immune system/response, antigen and antibody, serotyping for epidemiological purposes
You would mix antibody and antigen to see if they agglutinate
follow course of disease
23.
extrachromosomal DNA:: plasmids (antibiotic resitant)
24.
fluorescnce:: UV light instead of white light, fluorescent stain
25.
Fx of cell membrane: 1. Semipermeable osmotic barrier
2. Electron transport (in euk mitoch)(bact = no mito); oxidative phosphorylation (ATP synthesis)
3. Active transport; export of hydrolytic enzymes and other proteins (secretion)- nutrients in and waste out of cell
4. Cell wall biosynthesis- assembly of peptidglycan (done in the cytoplasmic membrane
5. Mesosomes: invaginations of cytoplasmic membrane, possible role in replication or cell wall synthesis
***Flagella are embedded in the plasma membrane, this is where they get their energy from
26.
fx of flagella: motility
chemotaxis
27.
glycocalyx:: capsule, slime layer
28.
Gram negative cell wall composition: lipopolysaccharides, two periplasmic spaces on either side of the peptidoglycan , has porins on outer membrane
29.
Gram positive cell wall chemical composition:: peptiodoglycans, teichoic acid, polysaccharides, proteins
30.
GRAM:: gram gives Reaction Arrngmt Morphology
31.
Lipopolysaccharide LPS - endotoxin:: toxicity due to Lipid A
heat stable at 60 C
Assoc w outer membrane
can cause endotoxic shock
32.
List the "laws" from Koch's postulates: 1. Causative agent must be found in every case of the disease.
2. Microbe must be isolated from the infected host or patient and grown in pure culture containing no other microorganisms.
3. Pure culture must reproduce the specific disease after inoculation into a new, normal, healthy susceptible animal.
4. The same organism must be recovered again from the experimentally infected host.
33.
lysozyme:: an enzyme that cleaves the glycosidic bond between the nam and the nag units, weakens bacteria cell wall, found in mucous secretions (tears, saliva). Affects already formed cell wall
34.
mechanisms for cell wall removal or prevention of cell wall formation: 1. lysozyme
2. penicillin
35.
Media types for pure culture?: Broth (liquid medium)
Agar (semisolid
36.
Negative Staining:: use india ink to stain background (for capsules)
37.
penicillin:: antibiotic that inhibits the last step in peptidoglycan synthesis, weakened cell wall causes bacterial cell to lyse.... Inhibits new cell wall
38.
phase contrast:: used to observe living specimens
39.
Pili (fimbriae) fx: common - allow bacteria to attach to "something"
sex - transfer of nucleic acid between bacteria
40.
Problems w koch's postulates: subclinical disease -you can be infected but have no symptoms yet still infect other.
cant grow all MO's, sometimes humans are only hosts (ethics)
polymicrobic etiology - biofilm (must be in community w other bact)
These all make it diffult to ID bacteria
41.
Proks v Euks: Proks - bacteria, no genetic material in nucleus (sprea throughout cell), no membrane bound organelles, single chroms, d.s. circular DNA, ETC and ATP synthesis in syto membrane (no mito), 70 s ribosomes
Euks - much larger, complex, membrane bound organelles, nucleus bound by membrane w/DNA, 80 s ribosomes.
42.
Properties of Agar?: semi-solid or a solid medium;
able to withstand incubation temps.
Comes from seaweed
Not digestable by bact
43.
Properties of Cell Wall: 1. Shape Maintenance
2. Resistance to osmotic changes
3. Gram stain rx determinant
44.
protoplast: a g+ cell that the pptg is lost and you only have the cellmembrane and the guts left (cell whose cell wall has been destroyed via lysozymes)
45.
Purpose of culturing?: ID, Diagnosis, Serology and to seperate pathogens from normal flora
46.
Sarcina: cuboidal cell arrngmts
47.
significance of capsule: 1. antiphagocytic - slime layer makes it difficult to be engulfed "slippery"
2. adherence - biofilms "dental plaque"
3. antigens for vaccines
48.
SImple staining:: one stain
49.
Special Staining:: used for flagella, spores and granules
50.
spheroplast: g- the pptg is lost but everything else is still there unless you also take off the outer membrane then you can actually get a protoplast from the g- as well.
51.
staphylo: cells arrng'd in clusters
52.
Steps of Gram staining: 1. primary stain (crystal violet) to a heat-fixed (death by heat) smear of a bacterial culture
2.addition of a trapping agent (Gram's iodine),
3. rapid decolorization with alcohol or acetone,
4. counterstaining with safranin.
53.
strepto: chains
54.
Structure of Cell membrane: phosphilipid bilayer, proteins embedded throughout, polar head, non polar tail, hydrophobic FA's
55.
tetrad: square formation
56.
These laws aided in growing bacteria in pure culture in 1880's: Koch's Postulates
57.
This media is used to enhance growth of a certain species over competitiors: Enrichment media
58.
This media type is for nutritionally fastidious bacteria (those with special growth requirement..: Enriched Media
59.
This media type provides a means by which it is easier to recognize a certain species from a mixed culture (make colonies diff colors): Differential
60.
Types of microscopy in micro?: brightfield
phase contrast
darkfield
fluorescnce
electron
61.
types of preparations for microscopic examination: wet mounts - living cells (looks for motility)
tissue sections - take very thing sx's)
bacterial smears - smear onto slide
62.
Variations of Helical bacteria: 1. Spirochete - corkscrew and thin (many turns)
2. Spirillum - corkscrew w/ few turns
63.
Variations of Rod shaped bacteria?: 1. Fusiform - long and pointy ends
2. Vibrio - comma shaped
3. Filamentous - long and branching
4. Pleomorphic - many shapes (literally)
5. Coccobacillus - short squatty rods, look like cocci
64.
We have 80 S ribosomes made of 40 s and 60 s subunits, describe those of bacteria: 70 S (30S and 50 S subunits)
65.
What acts as the selective agent and what acts as the differential agent in the selective and differential media type?: selective - salt
differential - mannitol
66.
What are the 5 I's for ID'ing collection of a specimen: Specimen collection --> inoculation--> incubation --> isolation --> inspection --> identification
67.
What are the 6 types of culture media?: 1. All purpose
2. Enriched Media
3. Selective
4. Differential
5. Selective and Differential
6. Enrichment
68.
What bacterial species are endospores characteristic of?: bacillus and clostridium
69.
What factors affect quality of a culture: temp = 37 C
pH
presence or absence of Oxygen
70.
What is a pure culture?: culture of a single species
71.
What is the best temp for culturing: 37 C
72.
What is the media type that inhibits growth of interfereing species. So pathogen can grow but the normal flora can't grow.???: Selective
73.
What is the media type that supports the growth of most bact.: All purpose
74.
What rigid structure gives bacteria its shape and serves as a target for antibiotics and disinfectents?: Cell Wall
75.
Why is a colony considered a pure culture?: Because it was derived from a single cell
