Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BACTE (LEC) LESSON 1 > Environmental Factors Influencing the Growth > Flashcards

Environmental Factors Influencing the Growth Flashcards

1
Q

What are the 3 factors inffluencing the growth of bacteria?

A

-pH
-Temperature
- Gaseous composition of atmosphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

T or F
Most bacteria grow best in neutral pH. (7.0-7.35)

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Types of bacteria grow best in cold temp (10-20°C) are called

A

Psychrophiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Bacteria that grow best in moderate temp. (20-40°C)

A

Mesophiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Bacteria grow best at high temperatures. (50-60°C)

A

Thermophiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

T or F most bacteria grow in the human body are mesophiles

A

True- near the body temp (37°C)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Diagnostic laboratories routinely incubate cultures for bacterial growth at what degree celsius?
A. 37
B. 36
C. 35
D. 38

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Fungal culture are incubated at what temp?

A

30°C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Example of Thermophiles bacteria

A

Pseudomonas sp.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Type of bacteria that require oxygen to grow.

A

Obligate aerobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Example of obligate aerobes bacteria.

A

M. tuberculosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

It can survive in the presence of O but not used O in metabolism.

A

Aerotolerant anaerobes/ facultative aerobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Cannot grows in the presence of Oxygen. Common in body.

A

Obligate anaerobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Common spp. of aerotolerant anaerobes.

A

Clostridium spp.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Can grow either with or w/o the presence of oxygen. Majoritiy in the body.

A

Facultative anaerobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Organisms grow best in increase of CO2

A

Capnophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Examples of capnophilic

A
  • Helicobacter
  • campylobacter
18
Q

Type of bacteria that require a decrease in O2.

A

Microaerophilic

19
Q

Examplen of facultative anaerobes.

A

E. coli

20
Q

Bacteria replicates through what?

A

Binary fission

21
Q

The time required for one cell to divide into two cells is called

A

Generation time or doubling time

22
Q

T or F
The fast growing bacteria usually grow for about 20 mins.

A

True

23
Q

T or F
For slow-growing bacteria, it usually takes 12 hours to grow.

A

False- 24 hrs.

24
Q

Example of fast and slow growing bacteria.

A

Fast (E. coli)
Slow (M. tuberculosis)

25
Q

T or F
If bacteria are in a balanced growth state, the increase in bacterial numbers is proportional to the increase of mass, protein content, nucleic acid content.

A

True

26
Q

What are the 4 phases of bacterial growth phase?

A
  • lag phase
  • log phase
  • stationary phase
  • death phase
27
Q

In this phase, there is no multiplication of bacteria because they’re only preparing to divide.

A

Lag phase

28
Q

Which is true about the log phase?
A. High multiplication, low no. of bacteria, short period of time
B. No multiplication, long period of time, low no. of bacteria
C. High multiplication, high no. Of bacteria, short period of time
D. No multiplication, low no. Of bacteria, short perdiod of time

A

C

29
Q

It is a phase in which nutrients are limited. The no. of bacteria is constant. (Equal no. of dead and living cells.)

A

Stationary phase

30
Q

Phase in which the no. of nonviable bacterial cells exceeds the no. of viable cells.

A

Death phase

31
Q

Adjustments phase: lag phase
Plate phase:

A

Stationary phase

32
Q

It is a procedure done to maintain the living bacteria alive.

A

Subculture

33
Q

3 ways in determination of cell numbers.

A
  • Direct microscope count
  • Direct plate count
  • Density measurement
34
Q

Which is/are true about Direct microscopic count?
A. It distinguishes between live and dead cells
B. All bacteria are already dead
C. Estimate the no. of bacteria present in specimen
D. Common in urine sample

A

B,C,D

35
Q

Which is/are not true about direct plate count?
A. Can be done by growing dillution of broth cultures on agar plates.
B. Can determine the no. of colony-forming units per milliliters (CFU/mL)
C. Limit is 500 colonies
D. Provides a count of viable cells only

A

C. Limit is only 300 colonies

36
Q

A measurement based on the density of bacterial broth culture in log phase.

A

Density measurement.

37
Q

The desity refers to what?

A

Turbidity/cloudliness

38
Q

This method is used to prepare a standard inoculum for antimicrobial susceptibility testing

A

Density measurement.

39
Q

method usually used in water analysis

A

Direct plate count

40
Q

What equipment is used in density measurement?

A

Spectrophotometer

BACTE (LEC) LESSON 1 (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions