Chapter 7 Fundamentals of Microbial Growth

Question 1

Cell division that produces new daughter cells and increase the total cell population.

Answer 1

Microbial growth

Question 2

Another method of asexual reproduction that certain fungi and some bacteria such as Hyphomicrobium reproduce this way.

Answer 2

Budding

Question 3

A type of formation that can be sexual or asexual while in bacteria it is asexual.

Answer 3

Spore formation

Question 4

The time it takes for a particular species of cell to divide.

Answer 4

Generation time

Question 5

As bacteria divide by binary fission, one cell turns to two, two to four, four to eight and so on.

Answer 5

Exponential

Question 6

Cells alter their gene expression in response to their new setting. For example they make new enzymes and transporter proteins so that they can take up and metabolize nutrients provided in their new environment

Answer 6

Lag Phase (1)

Question 7

If the growth conditions are optimized for nutrients, pH level and temperature, then once the cells have adjusted to their new environment, then will enter a phase of rapid exponential growth.

Answer 7

Logarithmic or Log phase (2)

Question 8

The population growth rate slows and eventually levels off as the number of cells dying matches the number of cells dividing.

Answer 8

Stationary phase (3)

Question 9

A critical point of waste buildup and decreasing nutrients, the cell begins to die.

Answer 9

Death Phase (4)

Question 10

Fresh growth medium is added at one end of the culturing device, while waste, nutrient-depleted medium, and excess cells are removed at another end fate system to maintain a constant culture volume.

Answer 10

Chemostat

Question 11

Organisms that tend to live in environments that are consistently cold like the Arctic. Temperatures ranging -20C to 10C.

Answer 11

Psychrophiles

Question 12

These grow in 0-30C temperatures and are associated with food-borne illnesses because they can grow in refrigerator and frozen foods.

Answer 12

Psychrotrophs

Question 13

These grow in between 10-50C which includes the body temperature. Found on the soil to streams to dwelling in eukaryotic systems.

Answer 13

mesophiles

Question 14

Typically found in compost piles and hot springs with temperatures ranging form 40-75C.

Answer 14

Thermophiles

Question 15

These prefer extremely hot temperatures ranging from 65-120C. These organisms are found in boiling water and volcanic vents.

Answer 15

Extreme thermophiles

Question 16

Bacteria that live near thermal’s vents are not only extreme thermophiles and have the ability to withstand the high pressure environment of the deep sea.

Answer 16

Barophiles

Question 17

Organisms that survive in high Salt environments.

Answer 17

Halophiles

Question 18

Reactive intermediates that include superoxide ions and hydrogen peroxide, both of which can rapidly damage cellular proteins and DNA.

Answer 18

Reactive oxygen species ROS

Question 19

Microbes that have the ability to detoxify ROS and safely use oxygen in their metabolism.

Answer 19

Aerobes

Question 20

Organisms that have an absolute dependence on oxygen for cellular processes and will die unless it is abundant.

Answer 20

Obligate aerobes

Question 21

Organisms that require small amounts of atmospheric oxygen and live in low oxygen settings where they can limit their exposure to ROS while still meeting their oxygen needs.

Answer 21

microaerophiles

Question 22

Organisms that do not require the use of oxygen in their metabolic processes.

Answer 22

Anerobes

Question 23

A group of microbes that span both aerobic and anaerobic environments. Switch hitters.

Answer 23

Facultative anaerobes

Question 24

Elements such as carbon, hydrogen, nongaseous oxygen and nitrogen are regard to build new cells and can be found in the organic and inorganic compounds microbe’s environment.

Answer 24

Essential nutrients

Question 25

Requires and external source of organic carbon scubas sugars, lipids, and proteins.

Answer 25

Heterotrophs

Question 26

Organisms known as self feeding that use a process called carbon fixation

Answer 26

Autotrophs

Question 27

The process to convert inorganic carbon into organic carbon.

Answer 27

Carbon fixation

Question 28

A process that can convert atmospheric nitrogen from a gas form to a non gaseous form like ammonia that can be used by other cellular life.

Answer 28

Nitrogen fixation

Question 29

The necessary substances that a cell can't make on its own.

Answer 29

Growth factors

Question 30

Organisms that are need multiple growth factors.

Answer 30

Fastidious

Question 31

Organisms that use light energy

Answer 31

phototrophs

Question 32

Organisms that break down chemical compounds for energy

Answer 32

chemotrophs

Question 33

Cooled at an angle in a test tube

Answer 33

slants

Question 34

cooled in an upright position

Answer 34

deep

Question 35

Useful for growing certain autotrophs and some heterotrophs. Chemically defined or precisely known composition.

Answer 35

defined media

Question 36

Used to grow fastidious organisms with complex growth requirements. Contains a mixture of organic and inorganic nutrients that are not fully defined.

Answer 36

Complex media

Question 37

Media formulated to visually distinguish one microbe from another.

Answer 37

Differential media

Question 38

A common example of a differential medium contains sheep red blood cells that serve as both a nutrient and a differentiation indicator.

Answer 38

Blood Apgar

Question 39

Breaks down red blood cells

Answer 39

Beta hemolytic

Question 40

Partial breaks down red blood cells

Answer 40

alpha hemolytic

Question 41

do not lyse red blood cells

Answer 41

gamma hemolytic

Question 42

A process that singles out bacteria that have specific properties.

Answer 42

selective media

Question 43

Most bacteria can not grow on this medium due to its high salt content.

Answer 43

mannitol salt agar MSA

Question 44

Methods designed to prevent the introduction of contaminating microbes to a patient, clinical sample or others in the health care setting.

Answer 44

Aseptic techniques

Question 45

A method or technique that isolates bacteria to identify the potential pathogen in a clinical sample.

Answer 45

Streak plate technique

Question 46

As cells divide their population increases to form a mound of cells known as

Answer 46

A colony

Question 47

Enumerates the number of cells in a small portion of the sample, and can be done using automated or manual procedures

Answer 47

Cell count

Question 48

Allows for direct enumeration of bacteria using agar plates. Applied to agar using either the spread plate method or pour plate method. After the incubation period, colonies are visible and can be counted.

Answer 48

Viable plate count

Question 49

A fast and easy way to indirectly measure cell number is to measure ____ of a liquid culture.

Answer 49

Turbidity

Question 50

Removes or reduces microbial populations to rend an object safe for handling.

Answer 50

Decontamination

Question 51

Eliminates all bacteria, viruses and endospore. Required for drugs. Objects used for medical procedures, and for lab media and glassware.

Answer 51

Sterilization

Question 52

Reduces microbial numbers. Used for cosmetics, foods, surfaces, and external medical equipment.

Answer 52

Disinfection

Question 53

The shortest period of time that a given temperature must be held to kill all microbes in a sample.

Answer 53

Thermal death time

Question 54

The minimum temperature needed to kill all microbes in a sample within ten minutes.

Answer 54

Thermal death point

Question 55

A machine that applies steam heat along with pressure to sterilize microbiological media and assorted medical or lab equipment.

Answer 55

Autoclave

Question 56

Formed when free floating bacteria adhere to a surface.

Answer 56

Biofilm

Question 57

A type of communication for bacteria to determine if their population is large enough to attack more tissue with the enzyme.

Answer 57

Quorum Sensing