BACTERIAL GROWTH CURVE AND BACTERIA

Question 1

Generation time can be every

Answer 1

30 minutes (E. coli) to every 24 hours (M. tuberculosis)

Question 2

Increase in cell size, preparation to multiply

Answer 2

Adjustment/Lag phase

Question 3

Increase in number of living cells; sensitive to antimicrobials

Answer 3

Exponential/Log phase

Question 4

Equal number of dead and alive cells (constant number of cells); Decrease in nutrients; Increase in toxins; Sporulation occurs (Bacillus, Clostridium)

Answer 4

Stationary/Plateau phase

Question 5

Increase in number of dead cells; more dead cells than alive cells

Answer 5

Death/Decline phase

Question 6

In general Culture media preparation contains

Answer 6

pH: 7.2-7.4, distilled/deionized water; Dissolved till clear and no particles seen

Question 7

Sterilization method for general culture media

Answer 7

AUTOCLAVE 121°C, 15PSI, 15 minutes

Question 8

Sterilization method for heat-labile or delicate media

Answer 8

116-118°C or membrane filtration (pore size 0.2-0.45μm)

Question 9

Types of Bacterial Culture

Answer 9

Pure culture, Mixed culture, Stock culture

Question 10

Most common solidifying agent in bacterial culture

Answer 10

Agarose

Question 11

Step after media sterilization and cooling

Answer 11

Add supplements (blood, vitamins, nutrients, or antibiotics)

Question 12

Volume of cooled media dispensed on a 100 mm petri dish

Answer 12

20-25 mL at 55-60°C

Question 13

LIQUID media examples

Answer 13

BHIB, THIO broth, TSB

Question 14

SEMI-SOLID media example

Answer 14

SIM (0.5-1% agar)

Question 15

SOLID media examples

Answer 15

TSI, MAC, CHOC (2-3% agar)

Question 16

SYNTHETIC/DEFINED media

Answer 16

For research, all content is known

Question 17

NONSYNTHETIC/COMPLEX media

Answer 17

Has some unknown content; examples: Nutrient broth, MAC

Question 18

TISSUE CULTURE media for obligate intracellular organisms

Answer 18

Chlamydia, Rickettsia - McCoy, Vero, HeLa, Hep2

Question 19

Sterilize and Dispense using petri dish

Answer 19

PLATED MEDIA

Question 20

Dispense and Sterilize, examples: Agar Deep, Agar Slant, Butt-Slant media

Answer 20

TUBED MEDIA

Question 21

Routinely used without special supplements for non-fastidious organisms (e.g., Nutrient agar, Trypticase soy)

Answer 21

SIMPLE/GENERAL PURPOSE/NUTRITIVE media

Question 22

Grow certain groups with supplements while suppressing other flora (e.g., APW, Selenite F, BCYE, THIO, LIM)

Answer 22

ENRICHMENT MEDIA

Question 23

For fastidious organisms (e.g., BAP, CAP)

Answer 23

ENRICHED MEDIA

Question 24

Visualizes metabolic differences of bacteria (e.g., MAC, BAP, EMB, HEA)

Answer 24

DIFFERENTIAL MEDIA

Question 25

Contains inhibitors to grow specific groups of bacteria (e.g., HEA, MAC, XLD, MSA)

Answer 25

SELECTIVE MEDIA

Question 26

Isolate bacteria with specific requirements (e.g., LJ, TCBS, Cysteine agar)

Answer 26

SPECIAL MEDIA

Question 27

Inhibitors that inhibit Gram-positive bacteria

Answer 27

Crystal violet, basic fuchsin, bile salt, sodium deoxycholate

Question 28

Inhibitors that inhibit Gram-negative bacteria

Answer 28

Phenylethyl alcohol, potassium tellurite, sodium azide

Question 29

Inhibitors for swarming Proteus spp

Answer 29

Alcohol, chloral hydrate

Question 30

Base agar for Neisseria

Answer 30

Chocolate agar

Question 31

Thayer Martin agar components

Answer 31

VCN (Vancomycin, Colistin, Nystatin)

Question 32

Modified Thayer-Martin agar components

Answer 32

VCNT (Vancomycin, Colistin, Nystatin, Trimethoprim)

Question 33

NYC agar components

Answer 33

VCAT (Amphotericin B)

Question 34

Martin-Lewis agar components

Answer 34

VCAT (Amphotericin B, Anisomycin)

Question 35

GC agar components

Answer 35

VCATL (Amphotericin B)

Question 36

NYC agar supports growth of

Answer 36

Neisseria, Ureaplasma, some Mycoplasma

Question 37

Antimicrobials for Neisseria culture media

Answer 37

Vancomycin, Lincomycin, Colistin, Nystatin, Amphotericin B, Anisomycin

Question 38

Antimicrobials for Neisseria growth inhibition

Answer 38

Vancomycin (Gram positive), Colistin (Gram negative), Nystatin, Amphotericin B (Fungi)