Microbiology Test 4

Front 1

steno-

Back 1

narrow range

Front 2

eury-

Back 2

wide range

Front 3

obligate

Back 3

necessary

Front 4

facultative

Back 4

not necessary

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philo-, philic-

Back 5

lover, loving

Front 6

phobe-, phobic-

Back 6

fearer, fearing

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extreme

Back 7

very high or low

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hyper-

Back 8

also extreme

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psychro-

Back 9

cold

Front 10

acido-

Back 10

low pH

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meso

Back 11

middle

Front 12

akali- or baso- or alkaline

Back 12

high pH

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thermo-

Back 13

hot

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halo-

Back 14

salt

Front 15

psychrophile

Back 15

grow in cold temperatures

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obligate psychrophile

Back 16

only grows at low (cold) temperatures

Front 17

eurythermic

Back 17

grow over wide range of temperatures

Front 18

hyperthermophile

Back 18

grows at very high/extreme temperatures

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heterotroph

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an organism that must obtain carbon in an organic form made by other living organisms such as proteins, carbohydrates, lipids, and nucleic acids

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autotroph

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an organism that uses CO2, an inorganic gas, as its carbon source--> not dependent on other living things

Front 21

chemotroph

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energy obtained by the oxidation of electron donors (substances) in their environments. these molecules can be organic (chemoorganotrophs) or inorganic (chemolithotrophs)

Front 22

Phototroph

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carry out photon capturing pigments to acquire energy from light--> photosynthesis (cyanobacteria/algae/or plants)

Front 23

What are the environmental factors that can fundamentally affect the function of metabolism, cell structures, and energy usage

Back 23

*Temperature
*Oxygen (gas) requirements
*pH
*Pressure

Front 24

True or False.
Microbes have an internal control for stable temperature

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FALSE. Only mammals and birds keep their internal temperature constant; all other organisms have no internal temperature homeostasis

Front 25

List the 3 cardinal temperatures

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1.) Minimum temperature - lowest temperature that permits a microbe's growth and metabolism
2.) Optimum temperature - promotes the fastest rate of growth and metabolism
3.) Maximum temperature - highest temperature that permits a microbe's growth and metabolism

Front 26

List the 3 temperature adaptation groups

Back 26

1.) Psychrophiles - optimum temperature below 15°C, capable of growth at 0°C
2.) Mesophiles- optimum temperature 20°C - 40°C, most human pathogens
3.) Thermophiles - optimum temperature greater than 45°C (some hyperthermophile bacteria can grow above 80°C.

Front 27

Which gases have the most influence on microbial growth?

Back 27

Oxygen and Carbon Dioxide

Front 28

what happens when oxygen enters cells?

Back 28

It produces TOXIC substances. Cells growing under aerobic conditions must have a way to detoxify these products

Front 29

What organisms grow best under higher concentrations of CO2 than normally present in the atmosphere?

Back 29

Capnophiles

Front 30

What are some of the toxic byproducts of oxygen introduction in cell?

Back 30

*Superoxide ion (O2)
*Peroxide (H2O2)
*Hydroxyl radicals (OH-)

Front 31

Most cells have developed __________ and mechanism that neutralize oxygen toxin byproducts

Back 31

Enzymes

Front 32

What are two enzymes that can counteract oxygen toxin byproducts?

Back 32

*Superoxide dismutase
*Catalase

Front 33

If a microbe is not capable of dealing with toxic oxygen by-products, it is forced to live in _______ _________ habitats (or is an ______________)

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Oxygen free; anaerobe

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Obligate aerobe

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cannot grow without oxygen

Front 35

Facultatitve anaerobe

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utilizes oxygen but can also grow in its absence (prefer oxygen but not required)

Front 36

microaeropilic

Back 36

requires only a small amount of oxygen

Front 37

Obligate anaerobe

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lacks the enzymes to detoxify oxygen so cannot survive in an oxygen environment

Front 38

Aerotolerant anaerobes

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do not utilize oxygen but can survive and grow in its presence

Front 39

What is the pH range where the majority of microorganisms can successfully replicate?

Back 39

between 6 and 8 (or near neutral pH of 7)

Front 40

Acidophiles

Back 40

grow at extreme acid pH

Front 41

Alkalinophiles

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grow at extreme alkaline pH

Front 42

neutrophiles

Back 42

grow at neutral pH

Front 43

How can many microbes keep an internal pH constant?

Back 43

By expelling protons and hydroxyl ions

Front 44

Which gram negative bacteria is present in patients with chronic gastritis and gastric ulcers?

Back 44

Helicobacter pylori

Front 45

Halophiles

Back 45

require a high concentration of salt

Front 46

osmophiles

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require a high concentration of solutes, such as sugar

Front 47

osmotolerant

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do not require high concentration of solute but can tolerate it when it occurs

Front 48

Barophiles

Back 48

deep see microbes that live under pressure many times higher than atmospheric pressure

Front 49

All cells need _______ to live and function.

Back 49

Water

Front 50

In what growth stage can microbes tolerate extremely dry conditions?

Back 50

Dormant stage (e.g, spore, cyst)

Front 51

Generation (doubling time)

Back 51

time required for a complete fission cycle under optimum conditions

Front 52

Each new fission cycle increases the population by a factor of ___________

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Two (which is exponential or logarithmic growth)

Front 53

What is a growth curve?

Back 53

the predictable pattern over time that populations of a certain microbe typically display

Front 54

What are the stages in the normal growth curve?

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1.) Lag phase - "flat" period of adjustment, enlargement; little growth
2.) Exponential (log) growth phase - a period of maximum growth that will continue as long as cells have adequate nutrients and a favorable environment
3.) Stationary phase - rate of cell growth equals rate of cell death caused by depleted nutrients and O2 excretion of organic acids and pollutants
4.) Death phase - as limiting factors intensify, cells die exponentially

Front 55

What is a batch culture?

Back 55

Culture where media is innoculated with a small sample of bacteria, then the growth in the media is measured over stages. Initially, growth is slow, but after a certain point, growth becomes logarithmic.

Front 56

In the stationary phase, the number of growing (alive) cells is ____________ to the number of dead cells.

Back 56

Equal

Front 57

Turbidometry

Back 57

simplest method of analyzing population growth by observing the degree of cloudiness/turbidity (reflects the relative population size)

Front 58

A method of analyzing population growth which looks at both the viable colony count and the direct cell count

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Enumeration of bacteria

Front 59

What is direct cell count?

Back 59

A count of all cells present automated or manual; either manual with observations under the microscope or automated with a Coulter counter or a flow cytometer

Front 60

Viable colony

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samples of culture taken in time intervals and spread on an agar plate; then the resulting colonies are counted

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Flow cytometer

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uses lasers and can distinguish living cells from dead cells

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genome

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sum total of genetic material of an organism

Front 63

chromosome

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majority, large complex DNA + protein (contains most of the genes for life under normal conditions)

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extrachromosomal DNA

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plasmids; small, replicating DNA (genetic info not necessary for life & growth under normal conditions)

Front 65

Characteristics of DNA?

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*Two strands twisted into a helix

*Consists of nucleotides with 3 parts

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Nucleotide

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Basic unit of the DNA structure

Front 67

What are the three components of a nucleotide?

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1.) a 5 carbon sugar - deoxyribose

2.) a phosphate group

3.) a nitrogenous base - adenine, guanine, thymine, cytosine

Front 68

Nucleotides covalently bond to form a sugar-phosphate linkage -- the __________________

Back 68

backbone

Front 69

Making an exact replication of DNA involves many different enzymes called ____________ ____________

Back 69

DNA polymerases

Front 70

DNA replication is ___________________ because each chromosome ends up with one _______ strand of DNA and one ______ strand.

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semiconservative; new; old

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Transcription

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DNA transcribed into RNA

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Translation

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RNA translated into Protein

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Characteristics of RNA?

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*Single-stranded polymer molecule made of nucleotide monomers

Front 74

RNA is composed of:

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1.) 5 carbon sugar-- ribose

2.) 4 nitrogenous bases -- adenine, uracil, guanine, cytosine

3.) a phosphate group

Front 75

List the 3 types of RNA

Back 75

1.) messenger RNA (mRNA): carries DNA message through complementary copy; message is in triplets called codons

2.) transfer RNA (tRNA): secondary structure creates loops; bottom loop exposes a triplet of nucleotides called anticodon which designates specificity and complements mRNA; carries specific amino acids to ribosomes

3.) ribosomal RNA (rRNA): component of ribosomes

Front 76

What are codons?

Back 76

the chemical language of mRNA