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Flashcards in Chapter 6 Deck (171)
1

All organisms require a source of these elements _____.

CHNOPS

2

CHNOPS stands for

carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur, represents the six most important chemical elements whose covalent combinations make up most biological molecules on Earth.

3

All organisms need other atomic elements in ____.

smaller quantities

4

______ needed for building molecules in the cell.

carbon source

5

______ use carbon dioxide. Not nutritionally dependent on other living things.

autotroph

6

______ use organic carbon.

heterotroph

7

______ used to generate (ATP) to run cell processes.

energy source

8

____ use chemical compounds for an energy source.

chemotroph

9

_____ use light as an energy source.

phototroph

10

______ use sunlight (nonliving environment) as an energy source.

photoautotroph

11

The carbon source for photoautotroph is ____.

CO2

12

The carbon source for chemoautotroph is ____.

CO2

13

The energy source (nonliving environment) for chemoautotrophs is ____.

simple organic

14

_____ energy source is obtained by metabolizing the organic matter of dead organisms.

saprobe

15

_____ energy source is obtained by utilizing the tissues, fluids of a live host.

Parasite

16

_____ energy source is sunlight and the carbon source is organic.

Photoheterotroph

17

_____ energy source is metabolic conversion of the nutrients from other organisms.

chemoheterotroph

18

Autotrophs (2)

photoautotroph
chemoautotroph

19

Heterotroph (4)

photheterotroph
chemoheterotroph
saprobe
parasite

20

The carbon source for heterotrophs is ___.

organic

21

The carbon source for autotrophs is ____.

C02

22

Two types of chemoheterotrophs

saprobes
parasites

23

Saprobes are free living organisms that feed on organic detritus from ____.

dead organisms

24

Saprobes are ____ of plants, animal matter, and dead microbes.

decomposers

25

_____ recycle organic nutrients

saprobes

26

______ are the majority of microbes causing human disease.

chemoheterotrophs
parasites ?

27

____ obtain nutrients from host cells/tissues.

parasites

28

Parasites often cause damage to tissues or ____.

even death

29

_____ live on the body.

Ectoparasites

30

_____ live in organs and tissues.

Endoparasites

31

____ live within cells.

intracellular parasites

32

____ unable to grow outside of a living host.

obligate parasites

33

Microbes eat by transporting nutrients across the ______.

cell membrane

34

_____ and _____ are the forms of movement from an area of higher concentration to an area of lower concentration. ______ uses protein channels.

passive transport and facilitated diffusion
facilitated diffusion

35

_______ are using proteins and energy to move against a concentration gradient.

active transport

36

Microbes eat via 3 methods

passive transport
facilitated diffusion
active transport

37

The concentration of solutes in an environment can affect _____. Too much can be detrimental.

bacteria

38

The availability of water is critically important because cytoplasm contains up to ___ water.

80%

39

Halophiles like high ____ environments.

salt (NaCl)

40

Extreme halophiles include some archaea that require ____ salt for growth.

15% - 30%

41

______ can tolerate higher salt concentrations.

Halotolerant
i.e. staphylococcus is an example remember MSA

42

Living membranes block the entrance and exit of larger molecules and permit the free movement of _____. (_____)

water
osmosis in living things

43

Osmotic relationships between cells and their environment is determined by the relative _____ of the solutions on either side of the cell membrane.

concentrations

44

______ is the diffusion of water through a selectively permeable membrane.

osmosis

45

Passageways in the permeable membrane allow free diffusion of water, but block ____.

other molecules

46

Osmosis continues until the concentration is ____ on both sides of the membrane.

equalized

47

_____ is the environment is equal in solute concentration tot eh cell's internal environment.

isotonic

48

In isotonic relationships there is ____ net change in cell volume. (stable)

no

49

Generally the most _____ environment for cells is isotonic.

stable

50

______ is when the solute concentration outside the cell is lower than inside the cell.

hypotonic

51

A slightly hypotonic environment can be _____ to bacteria cells.

favorable

52

Pure water provides the most _____ environment for cells because it has no solute.

hypotonic

53

The net direction of osmosis is from the ____ solution into the cell, and cells without walls swell and can _____.

hypotonic
burst

54

Slight hypotonicity is tolerated quite well by most bacteria because of their ______ walls.

rigid cell

55

_____ is when the environment has a higher solute concentration than the cytoplasm.

hypertonic
i.e. preservatives/salt-cure

56

A cell membrane will shrivel up inside the cell wall, plasmolysis, because there is not enough water, ______, left to keep it rigid.

osmotic pressure

57

Fresh pond water is an example of _____ conditions. In bacteria the cell wall protects them from _______. Amoeba (protozoa without cell wall) have a water ______ that moves excess water back out of the cell.

hypotonic
bursting
vacuole

58

High salt environment is an example of _____ conditions. ____ living in the Great Salt Lake absorb salt to make their cells more isotonic with the environment.

hypertonic
halobacteria

59

The range of temperatures for the growth of a given microbial species can be expressed as _____ cardinal temperatures.

three

60

The range of temperatures for the growth of a given microbial species can be expressed as what three cardinal temperatures.

minimum temperature
maximum temperature
optimum temperature

61

The ____ is the lowest temperature that permits a microbe's continued growth and metabolism; below this temperature, its activities are inhibited

minimum temperature?

62

The _____ is the highest temperature at which growth and metabolism can proceed. IF the temperatures rises slightly above maximum, growth will stop, but if it continues to rise beyond that point, the enzymes and nucleic acids will eventually become permanently inactivated (denatured) and the cell will ____.

maximum temperature
die

63

The ____ covers a small range, intermediate between the minimum and maximum, which promotes the fastest rate of growth and metabolism (rarely is the optimum a single point).

optimum temperature

64

Psychrophiles optimum temperature is below ___.

15C

65

Psychrophiles cannot grow above ____.

20C

66

Psychrophiles when stored at refrigerator temperature ____ rather than ______ them.

incubates rather than inhibits

67

The natural habitats of psychrophiles include natural habitats lakes, rivers, snowfields, polar ice, and _____.

ocean

68

Microbial cells are unable to control their temp and therefore take on the ambient temperature of their ____.

natural habitats.

69

Microbial cells survival is dependent on adapting to whatever temp variations are encountered in that ____.

habitat.

70

Amoebas and certain white blood cells ingest whole cells or large solid matter by a type of endocytosis called ____.

phagocytosis

71

Liquids, such as oils or molecules in solution, enter the cell through a type of endocytosis called ___.

pinocytosis

72

Chemicals that are necessary for particular organsims, which they cannot manufacture by themselves, are called ____.

essential

73

Depending on their natural habitats, some microbes have a ___ cardinal range, and others a ___ one.

narrow
broad

74

The typhus bacterium multiplies only in the range of 32C to 38C, and the ______ multiply most succesfully in tissues that are slightly below normal body temperatures (33C to 35C). Both have a ___ cardinal range.

rhinoviruses
narrow

75

Strains of Staphylococcus aureus growth within the range of 6C to 46C, and the intestinal bacterium _____ grows within the range of 0C to 44C, which is a broad cardinal range.

Enterococcus faecalis

76

Another way to express temperature adaptation is to describe whether an organism grows optimally in a ____, ___, or ____ temperature range.

cold, moderate, or hot

77

When the temperature adaptation is described as cold, moderate, or hot it is in reference to these 3 ecological groups.

psychrophile, mesophile, thermophile

78

Psychrophiles are rarely pathogenic because _____.

they have an optimum temperature of below 15C, which is much lower than the normal temperature of the body which is 37C.

79

Psychrotrophs grow ____ in the cold.

slowly

80

Psychrotrophs optimum temperature is between ___C to ____C.

25C to 30C

81

_________ can grow in your refrigerator and in food on the counter to cause food-borne disease.

Psychrotrophs

82

Examples of psychrotrophs

Staphylococcus aureus
Listeria monocytogenes

83

The majority of medically significant mircroorgansims are _______, organisms that grow at intermediate temperatures.

intermediate

84

The optimum growth temperature of _____ is 30C to 40C.

mesophiles

85

Human pathogens are ____ because the human internal body temperature is 37C, and the skin is closer to 30C.

mesophiles

86

Mesophiles inhabit _____, ____, and ____ as well as soil and water in temperate, subtropical, and tropical regions.

humans, animals, and plants

87

_____ microbes, which can survive short exposure to high temperatures but are normally mesophiles, are common contaminants of heater or pasteurized foods.

Thermoduric

88

Examples of Thermoduric microbes

Bacillus
Clostridum

89

______ grows optimally at temps greater than 45C.

Thermophiles

90

Thermophiles DNA and enzymes are ______ to high temps.

more resistant

91

The general range of growth of thermophiles is _____.

45C to 80C.

92

_____ grow well between 80C and 120C.

Extreme thermophiles

93

Strict thermophiles are so heat tolerant that researchers may use an ____ to isolate them in culture.

autoclave

94

Heat loving microbes live in soil and water associated with ____ , in compost piles, and in habitats directly exposed to the sun.

volcanic activity

95

The atmospheric gases that most influence microbial growth are ____ and _____, of these _____ gas has the greatest impact on microbial growth.

O2 and CO2
O2

96

Not only is oxygen an important respiratory gas, but it is also a powerful ____ agent that exists in many toxic forms.

oxidizing

97

As oxygen enters cellular reactions, it is transformed into several toxic products (4)

singlet oxygen (O)
superoxide ion (O2-)
hydroxyl radicals (OH-)
hydrogen peroxide (H2)2)

98

_____ is an extremely reactive molecule. It is one of the substances produced by phagocytes to kill invading _____.

Singlet Oxygen
bacteria

99

The buildup of singlet oxygen and the oxidation of membrane lipids and other molecules can damage and destroy a ___.

cell

100

Microbes fall into one of three categories.

1. those that use oxygen and detoxify it
2. those that cannot use oxygen nor detoxify it
3. those that do not need oxygen but can detoxify it

101

Bacteria growing in O2 need to deal with toxic oxygen products. Two step process requires two enzymes: ______ and _____.

superoxide dismutase
catalase (most common)

102

Step 1: 2O2- + 2H+ -SUPEROXIDE DISMUTASE--> H2O2 (hydrogen peroxide) + O2

and step 2: _____

2H2O2 --CATALASE --> 2H20 + O2

103

If a microbe is not capable of dealing with toxic oxygen by these or similar mechanisms, it is forced to live in habitats free of ____.

oxygen

104

_____ is similar to catalase in function, but no O2 is released.

Peroxidase

105

_____ can't grow without oxygen.

obligate aerobes

106

_____ likes oxygen, but can grow without it.

Facultative anaerobes

107

_____ can't tolerate any oxygen.

obligate anaerobes

108

_____ can tolerate oxygen, but does not use it.

aerotolerant anaerobes

109

_____ requires small % of oxygen.

microaerophiles

110

_______ grow best at a higher CO2 concentration than is normally present in the atmosphere.

Capnophiles

111

Examples of Capnophiles

Neisseria species
Streptococcus species

112

_____ is the acidity or alkalinity of a solution.

pH scale 0-14

113

The pH of pure water is ____.

7.0

114

Most organisms live in habitats between pH ___ and pH ___ because strong acids and bases can be damaging to the cell.

pH 6 - pH 8

115

_____ prefer neutral (close to 7) pH.

neutrophiles

116

____ prefer a basic/alkaline ph.

Alkaliphiles

117

Example of Alkaliphiles

Proteus species and UTI's

118

____ grow in an acidic environment.

Acidophiles

119

Example of Acidophiles

Lactobacillus and vaginal flora

120

Examples of Aerobes

most fungi, protozoa, and many bacteria, such as Bacillus species and Mycobacterium tuberculois

121

Examples of Microaerophiles

Organisms that live in soil or water or in mammalian hosts, not directly exposed to atmosphere; Helicobacteri pylori, Borrelia burgdorferi

122

Examples of faculative anaerobes

many gram-negative intestinal bacteria, staphylococci

123

Examples of anaerobes

Many oral bacteria, intestinal bacteria

124

Examples of Aeroteolerant anaerobes

certain lactobacilli and streptococci, clostridial species

125

Most microbes live in ____.

shared habitats

126

Interactions between microorganisms can have beneficial, harmful, or ____.

no particular effects on teh organisms involved

127

Ecological associations among microorganisms can be obligatory or ____ to the members.

nonobligatory

128

Ecological associations among microorganisms often involve ____.

nutritional interactions

129

The ocean depths subject organisms to increasing hydrostactic pressure. Deep-sea microbes called ______ exist under pressures that range from a few times to over 1,000 times the pressure of the atmosphere. These bacteria are so strictly adapted to high pressures that they will rupture when exposed to _____ atmospheric pressure.

barophiles
normal

130

______ is where two organisms live together in close partnership.

symbiosis

131

_____ is when organisms lives in an obligatory mutually beneficial relationship.

mutualism

132

_____ is when the host organism provides the parasitic microbe with nutrients and a habitat; _______ usually harms the host in some way.

parasitism
parasite

133

________ is the member called the commensal receives benefits, while its co-inhabitant is neither harmed nor benefited.

commensalism

134

S. aureus produces & releases
nutrients that Haemophilus
influenzae requires for growth.
• Haemophilus will grow in
satellite colonies near S. aureus
growth.
•Haemophilus _____.
•S. aureus does not (but is not
harmed)

benefits

135

_____ is a relationship between two or more free living organisms that is not necessary for their survival.

non-symbiotic

136

______ is an interrelationship between two or more free living organsisms that benefits them but is not necessary for their survival. The members cooperate and share _____.

synergism
nutrients

137

Gum disease, dental caries, and some bloodstream infections involve mixed infections of bacteria interacting _____.

synergistically

138

_______ is an association between free-living species that arises when members of a community compete.

antagonism

139

Biofilms are an example of ____

synergism

140

_____ form on many surfaces including teeth, lungs, catheters, pace makers, respiratory tubing, etc

biofilms

141

______ are mixed communities of different kinds of bacteria and other microbes that are attached to a surface and to each other, forming a multilayer conglomerate of cells and intracellular material.

biofilms

142

Bacteria uses _____ to interact with other members of the same species, as well as members of other species that are close by.

quorum sensing

143

________, mechanism by which bacteria regulate gene expression in accordance with population density through the use of signal molecules. ________ allows bacteria populations to communicate and coordinate group behaviour and commonly is used by pathogens (disease-causing organisms) in disease and infection processes.

Quorum sensing

144

Biofilms are ____ to most antibiotic treatments.

resistant

145

The growth of eukaryotic microorganisms can occur in various ways, but bacteria most often grow using a unique process called ____.

binary fission

146

Individual cell size does not increase before the actual fission event, but the most relevant aspect of growth is in their _____.

numbers

147

Steps in formation of a biofilm

1: pioneer bacteria colonize a surface
2. pioneers secrete extracellular material that helps keep them on the surface and serves as attachment point for later colonizers. Quorom sensing chemicals (red dots) are released by bacteria.
3. In many (but not all) biofilms, other species join and may contribute to the extracellular matrix and/or participate in quorum sensing with their own chemicals or the ones released by other species.
4. Biofilms serve as a constant source of bacteria that can "escape" and become free-living again

148

Binary fission refers to the fact that one cell become ___.

two

149

Steps in binary fission of rod-shaped bacterium.

1. a young cell
2. chromosome is replicated and new and old chromosome move to different sides of cell.
3. protein band forms in center of cell
4. septum formation begins
5. when septum is complete, cells are considered divided in to two daughter cells (genetically identical). Some species will separate, while others remain attached, forming chains or doublets for examples

150

_____ is asexual

binary fission

151

_____ or ____ is the time required for a complete binary fission cycle.

generation or doubling time

152

_____ increases the population by a factor of two.

generation

153

As long as the environment remains favorable, the doubling effect can continue at ____.

a constant rate

154

The average generation time for bacteria is _____ minutes under optimum conditions. The shortest generation times can be 10 to 12 minutes.

30 to 60 minutes

155

Mycobacterium leprae, the cause of Hansen's disease, has a generation time of _____ days as long as that of some animals.

10 to 30 days

156

Environmental bacteria commonly have generation times measured in ___.

months

157

Most pathogens have relatively ____ doubling times.

short

158

Salmonella enteritidis and Stphylococcus aureus, bacteria that cause food-borne illness, double in ____, which is why leavign food at room temperature has caused many cases of food-borne disease.

20 to 30 minutes
i.e. in a few hours , a population

159

____ is represented by 2 to the, 2 to the 2, 2 to the 3, etc. 2 to the n, n = ________.

doubling
generation number

160

Poltting logarithm number provides a ______, plotting raw data gives a _____.

straight line
curved slope

161

Stages in the normal growth curve

1. lag phase
2. exponential growth phase
3. stationary phase
4. death phase
some cells remain viable

162

The alternative is an automatic growth chamber called the _____, or continuous culture system.

chemostat

163

define stagesof bacterial growth curve

?

164

We can ____ bacterial population growth in liquid media by measuring the change in turbidity.

estimate

165

______ measures light passing through tube. As the broth gets "cloudier" less light comes through the side.

tubridometer

166

Turbidity is correlated with _____, but its not an exact number.

population size

167

_____ is a glass slide with a geometrical grid etched on it.

hemocytometer

168

When counting bacterial numbers you put your sample on this grid and view _____. Grids are uniform and represent a given volume so you can calculate the _____.

under the microscope.
number of cells per volume

169

Determine CFU/ml of the original sample by plating a sample and ____.

counting the resulting colonies

170

1 colony = ____ cell in original sample

1 bacterial

171

As long as you know the volume you plated, you can use math to figure out the ___ of the starting sample.

CFU/ml