Quiz 2 Pages 8-22 Flashcards Preview

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Flashcards in Quiz 2 Pages 8-22 Deck (71):
1

1) Organisms must be present in every case except healthy individuals
2) suspected organism must be isolated and grown In Pure culture
3) isolated pure culture organism must elicit the disease
4) microorganism must be isolated from the newly diseased subject

*Provides knowledge of the disease
*A starting point for curing infections

Koch's postulates

2

Salversan

Chemotherapy for syphilis, does not harm the patient
(arsenic)

3

Antibiotic penicillin
Clear zones
Scottish

Alexander Fleming

4

Invented agar
1) solid surface
2) not digested by most Microorganisms
3) withstands high temps

Eilshemius Hesse

5

Strep
Staph
Pallisade

Chains
Clusters

6

Based on wall composition
Gram stain
Acid fast stain

Differential staining

7

What an organism eats and what it releases

Metabolic capabilities/limitations
Carbohydrate utilization
Metabolic byproducts
Ability to ferment

Biochemical tests

8

Studied anthrax
Cultured Microorganisms from blood
Injected them into healthy animals
Infected Animals died
Isolated and cultured these Microorganisms from dead animals etc...

Robert koch's experiment

9

Using animal responses to organisms for classification

Serology

10

Anything that illicit an immune response

Antigens

11

Using specific antibodies in a multi well plate
Adding unknown bacterial specimen
If antibody recognizes bacteria positive test
See a color change

Elisa
Enzyme linked immuno absorbant assay

12

Run patient protein on a gel
Transfer to filter paper
Wash paper with antibodies to specific bacteria
Antibodies have dye coupled to them
Get color, got disease

Western blot

13

Semi-solid matrix of agarose or acrylamide
Run an electrical current
Molecules move based on size and charge
Use DNA fragments of known size to see progress
Visualize by radiation onto X-ray or ultraviolet fluorescence

Gel electrophoresis

14

Is the sample susceptible to the virus? Positive Id

Phage

15

Useful for id of fluorescent bacteria
Add fluorescent due tag to listeria antibody to milk

Flow cytometry

16

Base composition of cg / at ratio

Genetic Id

17

Restriction mapping: restriction endonucleases cut at specific sequences, run on gel to find pattern to match to known species

Genetic Id

18

PCR - polymerase chain reaction
Use primers to amplify a region of DNA to a level that can be run on a gel

Genetic id

19

1) denature DNA with high salt & temp
2) add a single stranded tagged probe
3) run on a gel and look for probe

Nucleic acid hybridization

20

Make copies of probe DNA
Collect grow muse denature sample
Mix with probe
Detect probe for positive id

DNA probe for known organisms

21

Ask a series of questions by running tests
Each answer reduces the possibilities by 1/2
Identifies organism by it's characteristics
Useful for pathogens

Dichotomous key

22

Resolving power = ocular magnification x objective
bright field

Multiple lenses

23

Light can move through slide, specimen, objective ocular to your eye without any loss to scatter

Oil immersion

24

Each Time light passes from one medium to another some light is lost
Oil immersion helps

Refraction

25

Chromophore is the positive ion
Bacterial cells are slightly negative
Crystal violet, methylene blue, malachite green & safranin

Basic dyes (stains)

26

Chromophore is the negative ion
negative staining (stains the background)
Clear organisms

Acidic dyes (stains)

27

Basic dye and alcohol, general cell properties

Simple stain

28

Bacteria will appear different depending on their characteristics

Differential stain

29

Hans Christian gram
1) heat fix cells to slide 2)add crystal violet 3) wash off excess 4) add iodine as a mordant 5) decolorize with alcohol 6)counter stain with Safranin 7) wash with water 8) blot dry

Gram stain

30

Purple
Retains crystal violet/iodine due to thicker cell walls
Sensitive to penicillin and cephalosporins

Gram positive

31

Pink
Colorless after alcohol
Counter stained with safranin
Thinner cell wall with lipopolysaccArides is disrupted by alcohol so crystal violet and iodine complex wash away
Relatively resistant to antibiotics due to the lipopolysaccArides in the cell walls

Gram negative

32

Binds strongly to bacteria/waxy cell wall
I'd for mycobacterium tuberculosis and M. leprae

1) heat fix smear 2) carbolfuchsin dye 3) heat to aid in penetration of the dye 4) wash with water 5) decolorize with alcohol 6) counter stain with methyl blue 7) acid fast organisms retain the dye

Acid fast stain

33

Examine live specimens
Syphilis diagnosed this way

Darkfield microscopy

34

Live specimens
Visualize internal structures

Phase contrast

35

Electron beam passes through a specimens
electrons impact fluorescent screen or photographic plate
Heavy metals for staining
View subcellular structures and viruses
Thin slices

Transmission electron microscopy

36

Electron Beam knocks an electron from the specimens surface
These are collected and used to create a 3D inmage on a plate or screen
Provide 3D views of intact specimens

Scanning electron microscopy

37

Temp, pH, osmotic pressure

Physical needs of Microorganisms

38

-/+ oxygen
C, N, S and Phosphorus

Chemical needs of Microorganisms

39

Incubators
Mesophyles like us
Psychrotrophs 0-30 Celsius

Temperature

40

Most bacteria neutral
Yeast & molds 5-6
Heliobacter pylori /80% of ulcers/koch's postulates/don't do research on themselves

pH

41

Created by the movement of water
Membrane
Diffusion important too
Plasmolysis - plasma membrane pulls away from cell wall, dehydrates bacteria to death, salt or sugar

Osmotic pressure

42

All Life forms are based on...

Carbon

43

Can survive with CO2 as their only carbon source

Autotrophs

44

Require a reduced carbon source ie, glucose methane fatty acids

Heterotrophs

45

Required for proteins, nucleic Acids and ATP

Nitrogen sulphur phosphorus

46

Survive with or without oxygen

Facultative anaerobes

47

Oxygen is toxic

Obligate anerobes

48

OH- (hydroxyl radical)
O2- (superoxide radical) SOD (superoxide dismutase) makes peroxide
H2O2 (hydrogen peroxide) catalase makes water and O2

Aerobic and aerotolerant organisms have enzymes that handle these toxic products

Oxygen reduction Produces 3 toxic compounds; all have extra electrons

49

Isolation and growth of a single organism
Aseptic technique
Sterile implements and media

How to get a pure culture

50

Obligate aerobe
Obligate anerobe
Facultative anerobe

Location of growth in broth indicates oxygen tolerance

51

Inoculum spread with a sterile loop
Goal is to grow individual colonies

Streak plate

52

Inserted into an agar slant identifies anaerobic metabolic activity

Stab

53

Inoculate liquified agar and Pour into a Petri dish
Allows for isolated colonies
Identifies anaerobic growth ability

Pour plate

54

Storage

Slant

55

All components and amounts are known, fastidious organisms, microbiological assays (to determine if a Microorganism is making a vitamin)

Chemically defined media

56

Exact components and their amounts are unknown i.e. Luria broth, nutrient broth, nutrient agar, chemoheterotrophic organisms

Complex media

57

Provides favorable conditions for target organism whole discouraging the growth of unwanted Microorganisms

Bismuth sulfate agar

Selective media

58

Allows all organisms to grow but appearances differ according to the species, Eosin methylene blue (e coli is green), Blood agar (streptococcus pyogenes, hemolysis)

Differential media

59

Using Anaerobic chambers equipt with air locks and filled with inert gas

Culturing anerobes

60

Utilizing specific growth factors to increase the #'s of desired organism,
(Example: enriching for halophiles by growing sample in subsequent increasingly higher salt media)

Enrichment

61

Time it takes for a population to double
Ecoli 22 min
2n
Logarithmic under optimal conditions

Generation Time

62

Lag, log, stationary, death

Bacterial growth curve

63

Cells adjusting to new media (cell division = cell death)

Lag phase

64

Exponential growth
Shortest generation Time
Division exceeds death
Kept I. This phase by adding nutrients and removing wastes

Log phase

65

Cell division = cell death
Nutrient level decreasing and waste level increasing

Stationary phase

66

Cell decision eclipsed by cell death
pH excessive

Death phase

67

Extrapolate colony count to the original undiluted sample

#colonies x mls x dilution factor = cells per ml

Serial dilution

68

Filtration, direct microscopic count, most probable #, turbidity

Ways to calculate the population of bacteria

69

Transmittance of Light shined through a sample onto a receiver

Helps determine log phase

Turbidity

70

Components provide favorable conditions for target organism while discouraging the growth of unwanted Microorganisms

Selective media

71

Growth of obligate a anarobes

Reducing media