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Flashcards in Lab Exam 1 Deck (59):
1

Place one drop of water in the center of the slide, transfer small amount of bacterial inoculum from the culture, spread into the size of a nickel, Air dry, heat fix.

Preparation of bacterial smears from solid medium

2

Wet mount

Determine how to do a wet mount

3

Let slide dry, heat fix, apply stain (1 to 2 minutes), gently wash with tapwater, blot slide with bibulous paper

Simple staining Crystal violet 20 to 60 seconds

4

Place a drop of Negrosin at one end of the slide, place loop full of inoculum in the drop, mix, place slide against the drop at 45° angle and spread, Air dry.

Negative staining

5

Prepare a slide (Inoculum, water, smear, heat fix). Flood slide with crystal violet. One minute. Wash with tapwater (Still purple). Flood slide with gram's iodine. One minute. Wash with tapwater. Decolorize with ethyl alcohol (Almost clear). Wash with tapwater. Counterstain with saffranin for 45 seconds. Wash with tapwater. Blot dry.

Gram staining

6

The bending power of light passing through air from glass slide to objective lens

Retractive index

7

When one lenses and focus, the other lenses will also have the same focal length, and can be rotated into position without further major adjustment.

Parfocal

8

Vibratory movement of the cells due to their bombardment by water molecules in the suspension

Brownian movement

9

Pair of cocci

Diplococcus

10

Chain of cocci

Streptococcus

11

Cluster of cocci

Staphylococcus

12

Packet of four cocci

Tetrad

13

Packet of eight cocci

Sarcina

14

Rod shaped, pair

Diplo bacillus

15

Rod shaped chain

Streptobacillus

16

Spiral bacteria, curved rods

Vibrios

17

Spiral, helical and Rigid

Spirilla

18

Spiral bacteria, helical and flexible

Spirochetes

19

Two Loopfulls of the cell suspension, spread suspension, allow the smear to air dry, heat fix.

Preparation of bacterial smears from broth medium

20

Requires the use of at least four chemical reagents that are applied sequentially to heat fixed smear

Differential staining

21

Imparts it's color to all cells, Crystal violet

Primary stain

22

Killing agent, increases the cells affinity for a stain, Used to intensify the color of the primary stain, grams iodine

Mordant, Crystal – Violet – iodine complex CV –I

23

Protein dehydrating agent and lipid solvent. In gram-negative cells, the alcohol increases the porosity of the cell wall by dissolving the lipids in the outer layer. CV – I complex is washed out. Gram-positive cells retain CV – I complex do you to thicker peptidoglycan. May or may not remove the primary stain from the entire cell or for only certain cell structures.

Decolorizing agent, ethyl alcohol

24

Contrasting color to that primary stain. Gram-negative.

Counterstain, safranin

25

Divides bacterial cells into two major groups, gram-positive and gram-negative

Gram stain

26

Malachite green

Used to stain free spores with impervious coats

27

Used to isolate specific groups of bacteria. They incorporate chemical substances that inhibit the growth of one type of bacteria while permitting growth of another, thus facilitating bacterial isolation.

Selective media (Phenylethyl alcohol auger, crystal violet auger, 7.5% sodium chloride auger)

28

Distinguish among morphologically and biochemically related groups of organisms.

Differential/selective media (macconkey agar, mannitol salt auger (staphylococci), eosin-methylene blue auger)

29

7.5% sodium chloride selects for staphylococci

Mannitol salt auger (differential selective)

30

Crystal violet allows the isolation of gram-negative bacteria by inhibiting gram-positive organisms

Macconkey agar (differential selective)

31

Lactose and dyes permit differentiation between enteric lactose fermentors and non-fermenters as well as the identification colon bacillus E. coli.

Eosin-methylene blue auger (differential/selective media)

32

Highly nutritious Materials for fastidious organisms. Blood, serum, or yeast extract.

Enriched media

33

Permits the demonstration of hemolytic properties particularly streptococci

Blood agar (enriched media)

34

No lysis of red blood cells

Gamma hemolysis, enriched media, blood agar

35

Incomplete lysis of red blood cells, greenish halo around bacterial growth.

Alpha hemolysis, enriched media, blood agar

36

Lysis of red blood cells, clear zones surrounding the colonies.

Beta hemolysis, enriched media, blood agar

37

Non-antigenic oxygen stable lysin

Streptolysin S

38

Use both aerobic and anaerobic pathways, fermentors of carbohydrates, degradation of glucose by the way of the glycolytic pathway

Facultative anaerobes

39

Inverted vile for the detection of gas production in fermentation

Durham tube

40

Design to differentiate among different groups of Enterobacteriaceae. All gram-negative bacilli capable of fermenting glucose with the production of acid and Gram-negative intestinal bacteria. (Differences in carbohydrate fermentation patterns and hydrogen sulfide production).

Triple sugar – iron auger test

41

Aerobic and anaerobic

Cellular respiration

42

Bioxidations in which molecular oxygen can serve as the final electronic acceptor

Aerobic

43

Bioxidations in which inorganic ions other then oxygen such as nitrate (no3-) or sulfate (so4 2-) can serve as the final electronic acceptor

Anaerobic

44

A bioxidative process not requiring oxygen in which an organic substrate serves as the final electronic acceptor, produces an organic acid that may be accompanied by gases, facultative anaerobes are usually fermenters of carbohydrates

Fermentation

45

Nutrient broth ingredients for all organisms, specific carbohydrate, pH indicator

Carbohydrate fermentation medium

46

Fermentation

Net two ATP, alcohol, lactic acid (in animals and some organisms)

47

One glucose to two pyruvic acid to Krebs cycle

Glycolytic pathway

48

Lack of carbohydrate fermentation. Alternative nutrients can be used as energy sources. These reactions liberate ammonia producing an alkaline environment. Phenyl red turns deep red in it now basic medium indicates aerobic respiration.

Peptones

49

Alkaline slant (red) and acid butt (yellow) with or without gas production (breaks in the auger butt)

Results of triple sugar iron auger test, glucose fermentation only, peptones used in the production of alkali

50

Acid slant (yellow) and acid butt (yellow) with or without gas production.

Results of the triple sugar iron Auger test, lactose and or sucrose fermentation

51

Alkaline slant (red) and alkaline butt (red) or no change (Orange – red) butt

Results of the triple sugar iron auger test, no carbohydrate fermentation, peptones catabolized under anaerobic and or aerobic conditions create ammonia.

52

A substrate for hydrogen sulfide production, blackening in the butt because of the precipitation of the insoluble ferrus sulfide

Sodium thiosulfate in TSI auger, indicates the production of h2s.

53

Differentiation of the principal groups of Enterobacteriaceae.
Indole, methyl red, voges – proskauer and citrate utilization

Imvic

54

Determines the ability of microorganisms to degrade the amino acid tryptophan

tryptophanase and Indole production test

55

Detects indole, cherry red reagent layer

Kovacs reagent

56

Detect the presence of a large concentration of acid end products, ph 4, indicative of E. coli. PH 6 indicative of e. Aerogenes

Methyl red test

57

Differentiates further along enteric organisms such as E. coli, E. Erogenes, and K. pneumoniae. Determines the production of nonacidic or neutral end products

Voges-proskauer test

58

Barrett's reagent, pink complex formed imparting rose color to the medium, indicates acetylmethylcarbinal

Voges-proskauer test

59

an organism can use citrate has its sole source of carbon. Indicates the presence of citrate permease, medium becomes alkaline, the carbon dioxide that is generated changes bromthemol blue indicator from green to Prussian blue

Citrate utilization test