Chapter 4 Dynamics or Prokaryotic Growth Flashcards Preview

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Flashcards in Chapter 4 Dynamics or Prokaryotic Growth Deck (126)
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1

All the bacterial cells that result from the replication of a single original bacterial organism are said to be a


A. population.

B. pure culture.

C. lag culture.

D. mutant culture.

B. pure culture.

2

The scientist that contributed most to the development of pure culture techniques was


A. Alexander Fleming.

B. Louis Pasteur.

C. Edward Jenner.

D. Robert Koch.

D. Robert Koch.


(keep your Koch clean, with pure techniques)

3

The solidifying agent used most successfully in bacterial nutrient media is


A. gelatin.

B. peptone.

C. agar.

D. starch.

C. agar.

4

Prokaryotic cells divide by a process known as


A. conjugation.

B. mitosis.

C. binary fusion.

D. binary fission.

D. binary fission.

5

In nature, bacteria


A. often grow in close association with many other kinds of organisms.

B. may remain in a prolonged exponential phase.

C. frequently synthesize structures such as slime layers.

D. may adhere to surfaces by means of pili and slime layers.

E. All of the choices are correct.

E. All of the choices are correct.

6

Biofilms


A. are a haphazard mixture of bacteria.

B. are a polysaccharide-encased community of microorganisms.

C. may enhance bioremediation efforts.

D. may protect organisms against harmful chemicals.

E. are a polysaccharide-encased community of microorganisms, may enhance bioremediation efforts AND may protect organisms against harmful chemicals.

E. are a polysaccharide-encased community of microorganisms, may enhance bioremediation efforts AND may protect organisms against harmful chemicals.

7

The simplest technique for isolating bacteria in growth media is referred to as the


A. pour plate method.

B. streak plate method.

C. serial dilution method.

D. MPN method.

B. streak plate method.

8

Bacteria may be stored


A. on a slant in the refrigerator.

B. frozen in glycerol solution.

C. lyophilized.

D. in broth at 37°C.

E. on a slant in the refrigerator, frozen in glycerol solution AND lyophilized.

E. on a slant in the refrigerator, frozen in glycerol solution AND lyophilized.

9

In the growth curve of a bacteria population, the bacteria are rapidly increasing in number in the


A. lag phase.

B. exponential (log) phase.

C. stationary phase.

D. decline phase.

E. boomer phase.

B. exponential (log) phase.

10

During which phase of growth are bacteria most susceptible to antibiotics?


A. lag

B. stationary

C. exponential (log)

D. decline

C. exponential (log)

11

When doing experiments with bacteria


A. it is usually not necessary to standardize which stage of growth is used.

B. it is best to use colonies as all the bacteria in a colony are at the same stage of growth.

C. it is best to use bacteria from the same stage of growth.

D. the age of the bacteria is not important.

C. it is best to use bacteria from the same stage of growth.

12

During which phase of the bacterial growth curve does the total number of viable cells decline?


A. stationary

B. lag

C. exponential

D. death

D. death

13

The lag phase of the bacterial growth curve is marked by


A. a decrease in cell mass.

B. dormant, metabolically inactive cells.

C. metabolically active cells.

D. vigorously dividing cells.

C. metabolically active cells.

14

Late log phase of the bacterial growth curve


A. is marked by the production of primary metabolites.

B. is marked by the production of secondary metabolites.

C. is a transition into the death phase.

D. shows a decline in cell numbers.

B. is marked by the production of secondary metabolites.

15

During which phase of the bacterial growth curve does a bacterial population become much more resistant to harmful conditions?


A. lag phase

B. exponential phase

C. stationary phase

D. late log phase

D. late log phase

16

A urine sample with more than 100,000 organisms is considered indicative of infection. A urine sample containing 5,000 bacteria, with a generation time of 30 minutes, sits for 3 hours before finally being assayed. How many bacteria will then be present within the sample?


A. 10,000

B. 64,000

C. 100,000

D. 320,000

D. 320,000

17

A pure culture in exponential growth phase has a bacterial concentration of 6.4 x 108 cells/ml. If the bacterium has a generation time of 1 h, how long ago was the cell concentration 8.0 x 107 cells/ml?


A. 1 h

B. 2 h

C. 3 h

D. 4 h

C. 3 h

18

In a rapidly multiplying bacterial population, cell numbers increase


A. arithmetically.

B. logarithmically.

C. linearly.

D. indirectly.

B. logarithmically.

19

The speed of enzymatic reactions approximately doubles for each


A. 5° C rise in temperature.

B. 10° C rise in temperature.

C. 20° C rise in temperature.

D. 30° C rise in temperature.

B. 10° C rise in temperature.

20

Generally the proteins of thermophiles


A. resist denaturation.

B. react more efficiently with DNA.

C. are easily denatured.

D. have a particular amino acid sequence that restricts bond formation.

E. are easily denatured AND have a particular amino acid sequence that restricts bond formation.

A. resist denaturation.

21

A hot tub (approx. 104 deg. F or 40 deg. C) would most likely contain


A. psychrophiles.

B. partiers.

C. thermophiles.

D. mesophiles.

D. mesophiles.

22

The optimal temperature for most human pathogens might be expected to range from


A. 35-40°C.

B. 20-45°C.

C. 15-25°C.

D. 93-98.6°C.

A. 35-40°C.

23

Bacteria on fish caught in the Arctic Ocean would


A. be psychrophiles.

B. be mesophiles.

C. continue to grow while the fish is in the refrigerator.

D. not grow very well in the refrigerator.

E. be psychrophiles AND continue to grow while the fish is in the refrigerator.

E. be psychrophiles AND continue to grow while the fish is in the refrigerator.

24

Mycobacterium leprae is typically found infecting the ears, toes and fingers of its host due to its


A. requirement for well-oxygenated blood.

B. easy access to those parts.

C. need for cooler temperatures.

D. long incubation period.

C. need for cooler temperatures.

25

Organisms that require gaseous oxygen for metabolism are referred to as


A. facultative aerobes.

B. obligate aerobes.

C. facultative anaerobes.

D. microaerophiles.

B. obligate aerobes.

26

Which of the following is/are obligate aerobes?


A. Clostridium botulinum

B. Escherichia coli

C. Micrococcus luteus

D. Helicobacter pylori

C. Micrococcus luteus

27

Organisms that are indifferent to the presence of oxygen and do not use it are


A. aerotolerant anaerobes.

B. facultative anaerobes.

C. obligate aerobes.

D. microaerophiles.

A. aerotolerant anaerobes.

28

The enzymes that deal with toxic oxygen-containing molecules is/are


A. glycolase.

B. superoxide dismutase.

C. catalase.

D. hydrogen peroxidase.

E. superoxide dismutase AND catalase.

E. superoxide dismutase AND catalase.

29

Shake tubes are used to determine the


A. pH requirements for bacterial growth.

B. temperature requirements for bacterial growth.

C. oxygen requirements for bacterial growth.

D. salt requirements for bacterial growth.

C. oxygen requirements for bacterial growth.

30

The optimum pH for growth of most species of bacteria is


A. pH 5.

B. pH 7.

C. pH 9.

D. pH 6.

B. pH 7.