Bio Final

Question 1

positive coagulase test

Answer 1

solid clot

Question 2

gram negative rod

Answer 2

e. coli, B meg

Question 3

K/K reaction on lactose slant

Answer 3

no sugar fermented

Question 4

bacteriostatic

Answer 4

inhibits growths of microbes, doesn’t kill them

Question 5

indole positive, gram -, green metallic colonies on EMB

Answer 5

E coli

Question 6

plaque forming units

Answer 6

4.5 x 10^7

Question 7

blood agar plate, partial breakdown of hemoglobin in RBC –> greenish discoloration, what type of hemolysis

Answer 7

alpha

Question 8

antiseptic

Answer 8

• alcohol
• betadine
• inhibits microbial growth
• kills microorganisms

doesn’t damage living tissue

Question 9

coag positive, catalase positive, gram positive

Answer 9

s aureus

Question 10

positive methyl red

Answer 10

red

Question 11

MacConkey agar selective for ___ and differential for ___

Answer 11

lactose fermentation

Question 12

barritts A and B associated with

Answer 12

voges proskauer test

Question 13

downside of assessing bacterial cultures by turbidometric method

Answer 13

non viable cells are indistinguishable form viable

Question 14

bacteriophage are viruses that infect bacterial cells

Answer 14

components:

• head
• capsid
• sheath
• tail

Question 15

on a tsi slant hydrogen sulfids production would be indicated by ___ precipitate

Answer 15

black

Question 16

T/F: s aureus produces a hemolysin called alpha toxin that causes a wide clear zone of beta hemolysis on blood agar

Answer 16

true

Question 17

positive catalase test

Answer 17

bubbling after addition of reagent to cells

Question 18

steps of lytic phage infection

Answer 18

• recognition
• penetration
• replication
• release

Question 19

ingredient in MacConkey that makes it selective

Answer 19

bile salts, crystal violet

Question 20

method used to test antimicrobial sensitivity of microorganisms

Answer 20

kirby bauer

Question 21

(gamma) y-hemolysis on a blood agar plate =

Answer 21

no clearing

Question 22

which is true ABOUT thermal death point

Answer 22

thermal death point is the lowest temperature at which a population of an organism is killed

Question 23

characteristics of bacteriophage

Answer 23

• Teven phages infect e coli
• nucleic acid is encased in protein capsid
• they exhibit specificity to hosts
• obligate intracellular parasites

-dont: contain metabolic machinery

Question 24

what does enzyme catalase do

Answer 24

breaks down toxic H2O2

Question 25

characteristics of endospores

Answer 25

• more resistant to heat stress
• contain calcium dipicolinate
• produced by bacillus
• macromolecules less susceptible to denaturation

Question 26

chem agents and use

Answer 26

• chlorine — water pathogens
• ethylene oxide – plastic petri dishes
• sterilant – surgical equip
• sanitizers – cooking equipment

not: disinfectants– applied to skin before surgery

Question 27

positive oxidase test, organism has

Answer 27

cytochrome c

Question 28

elevated temp kills microorganism bc of

Answer 28

enzyme denaturing
protein unfolding
loss of DNA structur

Question 29

function of durham tube

Answer 29

collect gas produced by fermentation

Question 30

bacterial cells that have phage DNA integrated into their DNA

Answer 30

lysogens

Question 31

MacConkey 24 hrs 37c, red colonies

Answer 31

gram -, ferments lactose

Question 32

characteristics of streptococcus

Answer 32

• facultative anaerobe
• gram +
• chains
• spherical

doesn’t produce catalase

Question 33

disinfectants

Answer 33

chem agents applied to inanimate objects to kill microorganisms

Question 34

of bacteria/mL of an original culture if you transferred 1 mL of culture into 99 mL of sterile water and add .1 mL to agar and get 265 colonies

Answer 34

2.65x10^5

Question 35

enteric bacteria

Answer 35

• faculatative anaerobes
• gram -
• rods
• in intestines

not spore former

Question 36

distinguishing factor that strep are separated into by lancefield groups

Answer 36

amount of hemolysis

Question 37

former name of HAIs

Answer 37

nosocomial infections

Question 38

spectrophotometer is used to measure optical density , measurement of

Answer 38

turbidity

Question 39

organism correctly matched with metabolism relationship to oxygen

Answer 39

aerotolerant – only ferments

Question 40

in order to replicate a virus will

Answer 40

hijack host machinery

Question 41

indole

Answer 41

cleavage product of tryptophan

Question 42

nose swab, streak on mannitol salt agar, reddish

Answer 42

cannot ferment mannitol

Question 43

T/F: thermal death time is the lowest temperature at which a population of a target organism is killed in 10 minutes

Answer 43

f

Question 44

you dilute 1 ml from a 10 ml starter culture into 99 ml of liquid, total dilution is

Answer 44

10^-2A

Question 45

gram -, coccus, oxidase +

Answer 45

neisseria

Question 46

viral structure that contains genome

Answer 46

nucleocapsid

Question 47

tsi slant, fermentation

Answer 47

red to yellow

Question 48

characteristics of staph

Answer 48

halotolerant

• gram +
• non-spore forming
• part of human microbiota

not motile

Question 49

zone of inhibition

Answer 49

diameter, in mm

Question 50

positive oxidase test

Answer 50

reagent turns purple on end of swab