bacterial culture growth curve

Question 1

observed when microbes are cultivated in batch culture=

Answer 1

closed vessel, limited nutrients

Question 2

usually plotted as

Answer 2

logarithm of cell number vs time

Question 3

has 4 phases

Answer 3

Lag

Exponential (Log)

Stationary

Death (Decline)

Question 4

Lag phase

Answer 4

no increase in cell numbers

Question 5

Exponential (Log)

Answer 5

maximal rate of division and population growth

Question 6

Stationary

Answer 6

population growth ceases - death rate = division

Question 7

death (decline)

Answer 7

population number decreases

Question 8

in the LAG PHASE cells are

Answer 8

synthesizing new components

Question 9

in the LAG PHASE cells are preparing for

Answer 9

exponential phase (dedicated growth)

Question 10

in the LAG PHASE cells are replenishing

Answer 10

spent materials, making new ones

Question 11

in the LAG PHASE cells are adapting to

Answer 11

new medium or other conditions

Question 12

in the LAG PHASE cells are repairing

Answer 12

damage

Question 13

the LAG PHASE varies in

Answer 13

length (can be so short, its undectable)

Question 14

exponential phase aka

Answer 14

log phase

Question 15

in the EXPONENTIAL PHASE (LOG) rate of growth is

Answer 15

constant

Question 16

in the EXPONENTIAL PHASE (LOG) the population is most

Answer 16

uniform in terms of chemical & physical properties

Question 17

in the EXPONENTIAL PHASE (LOG) all cells are dedicated to

Answer 17

growth

Question 18

in the EXPONENTIAL PHASE (LOG) bacteria are MOST

Answer 18

susceptible to antibiotics

Question 19

in the STATIONARY PHASE total number of

Answer 19

viable cells remans constant

Question 20

in the STATIONARY PHASE no net growth in number of cells because

Answer 20

reproductive rate equals death rate

Question 21

in the STATIONARY PHASE as many cells dying as being

Answer 21

replicated

Question 22

in the STATIONARY PHASE cells are changing to become more

Answer 22

resistant to harsh conditions

Question 23

in the STATIONARY PHASE bacteria are MOST

Answer 23

resistant to antimicrobials

Question 24

why enter stationary phase?

Answer 24

inhospitable environement

low nutrients/O2
high wastes or population density

Question 25

starvation response adaptations in the STATIONARY PHASE

Answer 25

morphological changes production of starvation proteins production of secondary metabolities including antibiotics & antimicrobial compounds can lead to increased virulence

Question 26

what are the morphological changes in starvation response adaptations

Answer 26

endospore formation decrease in size condense the nucleoid

Question 27

in the DEATH PHASE, why do cells die?

Answer 27

limited nutrients buildup of toxic wastes

Question 28

in the DEATH PHASE cells are viable but not

Answer 28

culturable

Question 29

in the DEATH PHASE many cells undergo programmed

Answer 29

apoptosis (cell death)

Question 30

what are the 2 categories for cell growth

Answer 30

physical and chemical

Question 31

what are physical requirements for cell growth

Answer 31

temp pH change osmotic pressure

Question 32

what are chemical requirements for cell growth

Answer 32

carbon nitrogen, sulfur, phosphorous trace elements organic growth factors oxygen availability

Question 33

optimal temp definition

Answer 33

is the temp at which a procedure is best carries out

Question 34

cardinal groups definition

Answer 34

based on the optimal temp range for organism's growth

Question 35

what are the cardinal groups

Answer 35

psychrophiles psychrotrophs mesophiles thermophiles hyperthermophiles

Question 36

thermophiles optimal temp:

Answer 36

60-65 degrees C

Question 37

hyperthermophiles optimal temp:

Answer 37

75-80 degrees C

Question 38

mesophiles optimal temp:

Answer 38

35-40 degrees C

Question 39

psychrotrophs optimal temp:

Answer 39

25-30 degrees C

Question 40

psychrophiles optimal temp:

Answer 40

10-15 degrees C

Question 41

what are the pH cardinal groups

Answer 41

acidophiles neutrophiles alkalophiles

Question 42

alkalophiles optimal pH

Answer 42

8.5-11.5

Question 43

acidophiles optimal pH

Answer 43

1-5.5

Question 44

neutrophiles optimal pH

Answer 44

5.5-7

Question 45

neutrophiles optimal pH

Answer 45

5.5-7

Question 46

cellular pH regulation

Answer 46

some synthesize special proteins that provide protection from toxic pHs change pH of their habitat by producing acidic or basic waste products

Question 47

osmotic pressure cardinal groups

Answer 47

extreme/obligate halophiles facultative halophiles

Question 48

extreme/obligate halophiles optimal concentration of salt

Answer 48

above 30% NaCl

Question 49

facultative halophiles optimal concentration of salt

Answer 49

2& NaCl

Question 50

what phases are heterogeneous

Answer 50

lag stationary

Question 51

what phase is homogeneous

Answer 51

exponential (Log)

Question 52

what phase is most susceptible to antimicrobials

Answer 52

Exponential (Log) Phase

Question 53

what phase is Most resistant to antimicrobials

Answer 53

Stationary Phase

Question 54

what phase Beginning to produce endospores (if applicable)

Answer 54

Stationary Phase

Question 55

What are some characteristics and observations that can be made of cells in the stationary phase?

Answer 55

The total number of viable cells remains constant because reproductive rates equals death rate. This means as many cells that are dying as being replicated. Cells begin to change and become more resistant to harsh conditions. The cells go through starvation response this includes: endospore formation, decrease in size, and condensing the nucleoid.

Question 56

which cardinal group make humans sick

Answer 56

mesophiles

Question 57

which cardinal groups spoil refrigated groups

Answer 57

psychrophiles psychrotrophs

Question 58

which cardinal group can spoil room temp food

Answer 58

psychrotrophs

Question 59

which cardinal group can spoil refrigated frozen but NOT room temp

Answer 59

psychrophiles

Question 60

which cardinal group can spoil refrigated frozen room temp

Answer 60

psychrotrophs