Chapter 5

Question 1

bacterial and archaean cells reproduce asexually via……

Answer 1

binary fission

Question 2

what ensures proper division during of the bacterial cell cycle

Answer 2

two checkpoints

Question 3

the interval required to progress through the cell cycle and produce two daughter cells

Answer 3

generation time or doubling time

Question 4

how many daughter cells are produced at the end of the bacterial cell cycle

Answer 4

two

Question 5

in pathogens a ________ doubling time means a _______ incubation period of disease

Answer 5

shorter
shorter

Question 6

bacteria adapt to their new environment; no cell division occurs

Answer 6

lag phase

Question 7

exponential growth; human disease symptoms usually develop

Answer 7

log phase

Question 8

reproductive and death rates equalize

Answer 8

stationary phase

Question 9

accumulation of waste products and scarcity of resources cause the population to die

Answer 9

decline phase

Question 10

a subset of bacterial cells that maintain a low rate of metabolism

Answer 10

persister cells

Question 11

persister cells are unaffected by what

Answer 11

antibiotics

Question 12

when antibiotic is withdrawn from persister cells, these cells can……..

Answer 12

repopulate the colony

Question 13

are a response to nutrient limitation

Answer 13

endospores

Question 14

how many genera are endospore forming and what are they

Answer 14

2
bacillus and clostridium

Question 15

are bacillus and clostridium gram positive or gram negative

Answer 15

gram positive

Question 16

what is an example of a diseases caused by bacilli

Answer 16

anthrax

Question 17

what is an example of a disease causes by clostridium

Answer 17

tetanus or botulism

Question 18

endospores are highly resistant to _______ and __________

Answer 18

heat and desiccation

Question 19

what phase are endospores formed in

Answer 19

stationary

Question 20

returning favorable environment conditions cause the protective layers of the endospore to _________

Answer 20

break down

Question 21

after the protective layer of endospores break down, what happens

Answer 21

the spore germinates into a vegetative cell

Question 22

between what degrees celsius are psychrophiles most optimal for growth

Answer 22

-10 and 20

Question 23

between what degrees celsius are psychotrophs most optimal for growth

Answer 23

0 and 30

Question 24

between what degrees celsius are mesophiles most optimal for growth

Answer 24

10 and about 50

Question 25

between what degrees celsius are thermophiles most optimal for growth

Answer 25

40 and about 72

Question 26

between what degrees celsius are hyperthermophiles most optimal for growth

Answer 26

about 68 and 110

Question 27

the majority of species grow optimally at a _________ pH

Answer 27

neutral

Question 28

what are species called that growth optimally at a neutral pH

Answer 28

neutrophiles

Question 29

acid tolerant bacteria

Answer 29

acidophiles

Question 30

what are two examples of acidophiles

Answer 30

lactobacillus and streptococcus

Question 31

extreme acidophilus are typically __________

Answer 31

archaea

Question 32

grow best at pH levels above 9

Answer 32

alkaliphiles

Question 33

need salty/hypersaline conditions for optimal growth

Answer 33

halophiles

Question 34

what prefers 2-5% NaCl

Answer 34

vibrio cholerae

Question 35

what is an example of an extreme halophile

Answer 35

halo bacterium salinarium

Question 36

what percent of NaCl do extreme halophiles grow at

Answer 36

20-30%

Question 37

what is an example of a nonhalophile

Answer 37

E. coli

Question 38

What percent of NaCl do nonhalophiles grow best at

Answer 38

less than 2%

Question 39

What is an example of a halotolerant bacteria

Answer 39

staphylococcus

Question 40

what percent of NaCl do halotolerants grow best at

Answer 40

non saline or slightly saline but only up to 8%

Question 41

requires oxygen to grow

Answer 41

obligate aerobes

Question 42

live in low oxygen environments

Answer 42

microaerophiles

Question 43

do not or cannot use oxygen

Answer 43

anaerobes

Question 44

species are insensitive to oxygen

Answer 44

aerotolerant

Question 45

are inhibited or killed by oxygen

Answer 45

obligate anaerobes

Question 46

grow either with oxygen or in reduced oxygen environments

Answer 46

facultative anaerobes

Question 47

require an atmosphere low in oxygen and rich in carbon dioxide

Answer 47

capnophilic bacteria

Question 48

what are the two basic types of culture media

Answer 48

complex medium and chemically defined medium

Question 49

some components are exactly known, but other components include plant digests, animal digests, or yeast extracts or unknown composition

Answer 49

complex medium

Question 50

the precise chemical composition of all additives is known

Answer 50

chemically defined medium

Question 51

inhibits growth of certain species and allows the growth of others

Answer 51

selective medium

Question 52

contains specific chemical to indicate species that possess or lack a biochemical process

Answer 52

differential medium

Question 53

some fastidious organisms require an ____________ containing specific nutrients

Answer 53

enriched medium