Chapter 7

Question 1

Increase in cellular constituents

Answer 1

growth

Question 2

Period of apparant inactivity during which the cells are adapting to a new environment and synthesizing new cell components. Short & very long.

Answer 2

lag phase

Question 3

Period during which the organisms are growing at the maximal rate possible given their genetic potential, smooth curve.

Answer 3

exponential phase

Question 4

Period in which teh number of viable microbes remains constant either because they metabolically stop reproducing or because the reproductive rate is balanced by the rate of cell death.

Answer 4

stationary phase

Question 5

Why does growth cease??

Answer 5

• Nutrients used up
• Oxygen used up
• Toxic waste produced

Question 6

Starved cells may enter a state called _____________, a dormant state relieved by an appropriate change in environment.

Answer 6

VBNC - viable but nonculturable

Question 7

The length of time it takes for a population of microbes to double in number.

Answer 7

generation time

Question 8

The number of generations per unit time, usually expressed as the number of generations per hour.

Answer 8

mean growth rate constant (k)

Question 9

The number of cells per unit volume that are able to grow and reproduce.

Answer 9

viable cell count

Question 10

A process by which bacteria communicate and carry out certain activities.

Answer 10

quorum sensing

Question 11

A culture system with constant environmental conditions maintained through continual nutrient provision and waste removal.

Answer 11

continuous culture

Question 12

A type of continuous culture in which sterile medium in limiting quantities is fed in at same rate as media w/ microbes removed.

Answer 12

chemostat

Question 13

A type of continuous culture in which teh flow rate of medium through the vessel is automatically regulated to maintain a predetermined turbidity

Answer 13

turbirdostat

Question 14

Organisms that grow over a fairly wide range of water activity.

Answer 14

osmotolerant

Question 15

Organisms that require high levels of NaCl

Answer 15

halophiles

Question 16

Organisms that have optimum growth between pH 0-5.5

Answer 16

acidophiles

Question 17

Organisms that have optimum growth between pH 5.5-8.0

Answer 17

neutrophiles

Question 18

Organisms that have optimum growth between pH 8.5-11.5

Answer 18

alkaliphiles

Question 19

minimum, optimum, and maximum temp

Answer 19

cardinal temps.

Question 20

Organisms that have optimum growth at 15C or lower

Answer 20

psychrophiles

Question 21

Organisms that have optimum growth between 20C-30C

Answer 21

psychrotrophs

Question 22

Organisms with optimum growth between 20-45C

Answer 22

mesophiles

Question 23

Organisms with optimal growth between 55-65C

Answer 23

thermophiles (tide)

Question 24

Organisms with optimal growth between 80-110C

Answer 24

hyperthermophile

Question 25

Organisms completely dependent on oxygen.

Answer 25

obligate aerobe

Question 26

Organisms that do not require oxygen for growth, but grow better in its presence.

Answer 26

facultative anaerobe

Question 27

Organisms that ignore oxygen and grow equally in presence/absence of oxygen

Answer 27

aerotolerant anaerobe

Question 28

Organisms that require oxygen at levels in the range of 2-10% for growth and are damaged by normal atmospheric (20%). Basically need less oxygen

Answer 28

microaerophiles

Question 29

Organisms that grow more rapidly at increased barometric pressure.

Answer 29

barophiles

Question 30

Organisms that grow in harsh environments that would kill most living organisms.

Answer 30

extremophiles

Question 31

Complex involved in replication of the prokar. chromosome

Answer 31

replisome

Question 32

Starved cells may enter this state.

Answer 32

VBNC