Lesson 7

Front 1

Growth

Back 1

Increase in number of cells, not size, by binary fission

Front 2

Colony

Back 2

A group of cells originating from a single cell that can be seen with the naked eye

Front 3

Colony forming unit

Back 3

A measure of viable cells

Front 4

5 I's

Back 4

Inoculation: sample is placed into a container of medium

Incubation: incubator creates proper growth conditions

Isolation: a way to separate species

Inspection: observation micro or macroscopically

Identification: identify isolated microbe to species level

Front 5

Culture

Back 5

Microbe growing on media

Front 6

Inoculum

Back 6

Microbe added to media

Front 7

Inoculate

Back 7

Process of adding microbes to media

Front 8

Broth

Back 8

Liquid media

Front 9

Agar

Back 9

Solidifying agent derived from algae that is liquid at 100°C and solid at 40°C

Front 10

Chemically defined media

Back 10

Exact chemical composition is known

Front 11

Complex media

Back 11

Precise components are unknown

Extracts and digests of meat, plants, or yeasts (most bacteria grown on complex media)

Front 12

Selective media and an example

Back 12

Designed to encourage only growth of the desired microbe

Sabouraud agar pH of 5.6, mannitol salt agar, EMB agar

Front 13

Differential media and examples

Back 13

Contains substances that allow different microbes to be identified growing in the same media

EMB and MSA

Front 14

Enrichment culture

Back 14

Encourages growth of desired microbe (conditions like temperature, pH, salt concentration, light, nutrients, oxygen are specifically tailored to requirements of desired microbe

Front 15

Pure culture

Back 15

Contains one specific type of microbe

Front 16

Mixed culture

Back 16

More than one type of microbe

Front 17

Streak plate steps

Back 17

4 zones of growth created to isolate pure colonies

1. Bacterium aseptically streaked into zone 1 of plate

2. Loop flamed and cooled, zone 2 is streaked

3. Loop flamed and cooled, zones 3 and 4 are streaked

Front 18

Function of carbon in cellular function

Back 18

Most abundant element, used to make carbohydrates, proteins, lipids, and nucleic acids

Front 19

Function of nitrogen in cellular function

Back 19

Second most abundant, used to make proteins and nucleic acids

Front 20

Function of phosphorus in cellular function

Back 20

Used to make DNA, RNA, ATP, phospholipids

Front 21

Function of sulfur in cellular function

Back 21

Used to make vitamins and amino acids

Front 22

Function of trace elements in cellular function

Back 22

Needed in small amounts for enzymes to function

Front 23

Define aerobe, anaerobe, obligate aerobe, facultative anaerobe, aerotolerant anaerobe

Back 23

Aerobe - use oxygen

Anaerobe - don't use oxygen

Obligate aerobe - must have oxygen

Facultative anaerobe - uses oxygen when it's present but can grow without

Aerotolerant anaerobe - survives in presence of oxygen but doesn't use it

Front 24

Psychrophile optimum temp, habitat, and example

Back 24

-10 to -20°C

Glaciers and deep in oceans

Psychrobacter cryohaloentis

Front 25

Psychrotrophs optimum temp, habitat, and example

Back 25

10 to 30°C

Food at room temp or in the fridge

Listeria monocytogenes

Front 26

Mesophiles optimum temp, habitat, and example

Back 26

25 to 40°C

Animal hosts, soil, water

E. coli, M. tuberculosis

Front 27

Thermophile optimum temp, habitat, and example

Back 27

40 to 75°C

Compost piles, hot springs

Thermus aquaticus

Front 28

Cardinal temperature

Back 28

Each bacterial species grows a particular minimum, optimum, and maximum temp

Front 29

Minimum, optimum, maximum temperature

Back 29

Minimum: lowest temperature at which growth will occur

Optimum: temperature at which growth is most rapid

Maximum: highest temperature at which growth will appear

Front 30

Acidophile optimum pH, habitat, and example

Back 30

Below 6.5

Acidic environments

Helicobacter pylori

Front 31

Alkaliphile optimum pH, habitat, and example

Back 31

Above 7.5

Soda lakes and alkaline environments

Bacillus alcalophilus

Front 32

Neutrophile optimum pH, habitat, and example

Back 32

Between 6.5 and 7.5

Near neutral environment

E. coli

Front 33

Halophile

Back 33

Require high salt concentration (found in dead sea or great salt lake)

Halococcus

Front 34

Plate count

Back 34

Most common method that measures number of viable cells (pour plate ans spread plate methods)

- serial dilutions prepared and bacteria are diluted

- poured into plates and allowed to grow

- plate with the highest dilution will have the least growth

Front 35

How pour plate method is produced and where do colonies grow

Back 35

Bacteria are affected to liquid awareness then the mixture is poured into empty plates. Agar solidifies and the plate is incubated

Colonies grow in and on surface of agar

Front 36

How is the spread plate method produced and where do the colonies grow

Back 36

Bacteria are added to solid agar and spread over surface with sterile rod

Colonies grow only on the surface

Front 37

What is direct microscopic count and what are the pros and cons

Back 37

A ladder etched grid area has a known volume and area and you count the number of cells in a specific volume

Pro: no incubation time

Con: counts viable and dead cells

Front 38

Turbidity and how to measure it

Back 38

The more bacteria in a liquid culture the more turbid it becomes

A beam of light passes through test tube and the more the bacteria grow, the less light will pass through tube (spectrophotometer)

Front 39

Most probable number and how to tell a positive result

Back 39

Estimated number is bacteria in an original sample using a serial dilution (useful when microbes won't grow on solid media)

Positive result shown by gas production in lactose broth (helpful tip determine fecal coliform counts and used in water testing)

Front 40

Generation

Back 40

Division of one cell into two

Front 41

Generation time

Back 41

Time it takes for population size to double

Front 42

Growth curve

Back 42

Plot of growth of cells over time, used to calculate generation time and uses logarithmic scale

Front 43

Lag phase

Back 43

Period of adjustment with no growth

Front 44

Log phase

Back 44

Population is doubling

Slope of line can be used to calculate generation time

Front 45

Stationary phase

Back 45

Equal number of cells are dividing and dying due to depletion of nutrients, accumulation of waste products, or drop in pH

Front 46

Death phase

Back 46

Cells are dying

Front 47

Flash freezing

Back 47

Bacterial culture quickly Frozen at -50 to -95°C

Front 48

Lyophilization

Back 48

Bacterial culture flash frozen, vacuum removes water (cells dehydrated), results in powdery residue

Front 49

Nutritional categories of microbes

Back 49

Autotrophs, heterotrophs, phototrophs, chemotrophs

Front 50

Symbiosis

Back 50

Two organisms live together in close partnership

Front 51

Mutualism

Back 51

Organisms life and exist in an oblivious and mutually beneficial relationship

Front 52

Commensalism

Back 52

One organism benefits while the other is neither harmed nor benefited

Front 53

Parasitism

Back 53

Host organism provides parasitic microbe with nutrients and habitat while host is harmed