Abac Biol 2050 Tortora Chapter 6 (Branch)

Front 1

Physical Requirements

Back 1

_____ are environmental factors that influence growth include temperature, pH, and osmotic pressure.

Front 2

Psychrophiles

Back 2

_______ have an optimum growth temperature between -5° and 20°C.

Front 3

Psychrotrophs

Back 3

____ have an optimum growth temperature between 0o and 30oC

Front 4

Mesophiles

Back 4

____ have an optimum growth temperature between 20° and 50°C.

Front 5

37oC

Back 5

What is human body temperature?

Front 6

Thermophiles

Back 6

____ have an optimum growth temperature between 40° and 70°C.

Front 7

Hyperthermophiles

Back 7

____ have an optimum growth temperature above 70°C.

Front 8

7

Back 8

Most bacteria grow best in a medium with a pH ______

Front 9

Buffers

Back 9

___________are added to media to maintain a constant pH.

Front 10

Buffers

Back 10

____ combine with or contribute H+ or OH- as a function of pH.

Front 11

Acids

Back 11

Proton donors are called ____

Front 12

Bases

Back 12

Proton acceptors are called ____

Front 13

Acids

Back 13

________ have a high concentration of H+ and a low concentration of OH-

Front 14

Bases

Back 14

_________ have a low concentration of H+ and a high concentration of OH-

Front 15

Acidophiles

Back 15

___ are organisms that grow in acidic conditions

Front 16

Osmotic pressure

Back 16

________ is determined by the concentration of dissolved substances in the medium in which bacteria are growing.

Front 17

Hypotonic

Back 17

____ solutions have a low solute concentration

Front 18

Hypertonic

Back 18

____ solutions have a high solute concentration

Front 19

Turgor

Back 19

____ is pressure against the cell wall that occurs within a cell placed in a hypotonic solution

Front 20

Plasmolysis

Back 20

___ is shrinkage of the plasma membrane from the cell wall due to fluid loss

Front 21

Extreme (obligate) halophiles

Back 21

____ are organisms that require high concentrations of salt for growth.

Front 22

Facultative halophiles

Back 22

____ are organisms that do not require high concentrations of salt for growth but can grow in 2-15% salt.

Front 23

Photoautotrophs

Back 23

____ use light (radiant) energy and CO2 as a source of carbon.

Front 24

Photoheterotrophs

Back 24

____ use light (radiant) energy and organic compounds as a source of carbon.

Front 25

Chemoautotrophs

Back 25

____ use chemical energy(inorganic) and CO2 as a source of carbon.

Front 26

Chemoheterotrophs

Back 26

____ use chemical energy(organic or inorganic) and organic compounds as a source of carbon.

Front 27

Fastidious

Back 27

An organism is _________if it has a limited number of compounds that can be used as a carbon source.

Front 28

proteins
inorganic salts (NH4+, NO3-)
N2 (nitrogen fixation)

Back 28

Nitrogen sources are found in ____

Front 29

proteins
inorganic salts (SO4-2)
H2S

Back 29

Sulfur sources are found in ____

Front 30

Inorganic salts (PO4-3)
nucleic acids

Back 30

Phosphorus sources are found in ____

Front 31

Trace elements

Back 31

____ are elements required by microbes in very small quantities such as Cobalt, Zinc, Manganese

Front 32

Obligate (strict) aerobes

Back 32

___ are organisms that have an absolute requirement for oxygen.

Front 33

Obligate (strict) anaerobes

Back 33

____ are organisms that cannot multiply if oxygen is present, since it kills bacteria.

Front 34

Facultative anaerobes

Back 34

____ are organisms that can utilize oxygen if it is available but can grow, although less well, in its absence.

Front 35

Microaerophilic

Back 35

___ are organisms that require small amounts of oxygen (2%-10%) but higher concentrations are toxic.

Front 36

Aerotolerant

Back 36

____ are organisms that grow in the presence or absence of oxygen, but they derive no benefit from the oxygen

Front 37

Organic Growth factors

Back 37

_____ are small organic molecules that serve as subunits of biosynthetic macromolecules and cell components.(AA, lipids, vitamins, and nitrogen bases)

Front 38

Inoculum

Back 38

The microbes introduced into a culture medium to initiate growth are called the _____

Front 39

culture

Back 39

The microbes that grow and multiply in or on a culture medium is the ____

Front 40

Sterile

Back 40

____ is the absence of living organisms.

Front 41

Koch

Back 41

Scientist that developed the use of agar as a solidifying agent in media was ____

Front 42

Agar

Back 42

____ is the polysaccharide extract from algae used as a solidifying agent in media

Front 43

Synthetic (defined) medium

Back 43

____ is a media that consists of chemically pure materials added in known amounts.

Front 44

Complex (undefined) medium

Back 44

____ is media that consists of undefined nutrients such as ground meat, added in known amounts.(Yeast extract, peptone, digested plant products etc.)

Front 45

Nutrient agar or nutrient broth

Back 45

___ is undefined media that is rich in a variety of nutrients and can grow many different microbes

Front 46

Reducing media

Back 46

____ is media to which chemicals have been added to deplete molecular oxygen

Front 47

Capnophiles

Back 47

____ are organisms that require high concentrations of CO2

Front 48

Differential media

Back 48

Media used to distinguish organisms based on metabolic activity is _____

Front 49

Selective media

Back 49

____ is media that preferentially inhibit the growth of certain organisms.

Front 50

Enrichment media

Back 50

____ is media that enhance the growth of specific organisms.

Front 51

1,000,000

Back 51

How many bacteria are in a single pinpoint colony?

Front 52

Refrigeration(4oC)

Back 52

___ is the temperature that can be used for short-term storage.

Front 53

Deep-freezing at -50 to -95 oC

Back 53

___ is the temperature that can keep cultures viable for years.

Front 54

Lyophilization

Back 54

____ is quick freezing at -54 to -72 oC followed by sublimation.

Front 55

Binary fission

Back 55

The most common mode of asexual reproduction in bacteria is ____

Front 56

Generation time

Back 56

____ is the time it takes to complete one cell cycle.

Front 57

Bacterial growth curve

Back 57

_____ is tracing the growth of bacteria over time

Front 58

Lag phase

Back 58

Phase of growth that involves no increase in cell numbers is the _____

Front 59

Exponential phase (log) growth

Back 59

The time during which cell number increases exponentially is ______

Front 60

Stationary phase

Back 60

Growth phase reached when the numbers of viable cells stops increasing is _____

Front 61

Death phase

Back 61

Growth phase characterized by an exponential decrease in the number of viable cells ____

Front 62

Plate count
Filtration
Direct microscopic count
Most probable number method

Back 62

Name the direct measurements of microbial growth.

Front 63

Plate count
Filtration Most probable number method (estimates # of viable bacteria)

Back 63

Which counting procedures count only the number of viable cells that can grow?

Front 64

CFU (colony forming units)

Back 64

A _____ is the viable bacteria that multiply and form a colony.

Front 65

Serial dilution

Back 65

______ is the stepwise dilution of a substance in solution

Front 66

Filtration

Back 66

___ is the process of separating suspended bacteria from a liquid, by causing the latter to pass through the pores of a membrane

Front 67

Direct microscopic count

Back 67

Direct counting procedure that does not require incubation is ____

Front 68

Most probable number method

Back 68

An estimation of numbers in which samples are diluted until no growth occurs is _______

Front 69

Turbidity
Metabolic activity
Dry weight

Back 69

Name the procedures that count bacterial numbers by indirect methods.

Front 70

Turbidity

Back 70

____ is estimation of numbers by comparison of cloudiness to a standard.

Front 71

Scattering of light

Back 71

________ measures living and dead cells using a spectrophotometer

Front 72

Metabolic activity

Back 72

Measuring a metabolic product to estimate culture density.

Front 73

Dry weight

Back 73

______ is measurement of the mass of dried filamentous organisms.

Front 74

Akalinophiles

Back 74

Organisms that grow at high pH are ____