Exam 1 9/11 Nguyen Micro Flashcards

1
Q

All known life on earth is:

A

carbon-based

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Autotrophs

A

self feeders; making of own food by reducing CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Heterotrophs

A

cannot make their own food from CO2; must obtain food from outside sources (eating something else)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Photoautotrophs

A

Use light and CO2 to make food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Examples of photoautotrophs

A

Photosynthetic bacteria (green and purple sulfur), cyanobacteria, algae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Chemoautotrophs

A

Use chemicals (inorganic compounds) as reducing agents and CO2 to make food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What inorganic compounds can chemoautotrophs use to make food?

A

Hydrogen sulfide, sulfur, ammonium, ferrous ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

True or false: chemoautotrophs require light to make food

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

All human pathogens are:

A

heterotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Chemoheterotrophs another name

A

Organoheterotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Chemoheterotrophs cannot use ____ to make organic compounds; they must use ______

A

CO2; ready-made carbon (eating other organisms)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Photoheterotrophs

A

Use light and ready-made carbon to make organic molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Chemoheterotrophs

A

Use chemicals and ready made carbon to make organic molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Examples of photoheterotrophs

A

Purple and green nonsulfur bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Examples of chemoheterotrophs

A

most bacteria, all protozoans, all fungi, all animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What organism is limited by available O2?

A

obligate aerobes; tend to settle at top of test tube with lots of oxygen around

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What bacteria are not limited by available O2?

A

Obligate anaerobes; tend to settle at bottom of test tube with no oxygen around

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which bacteria grows in presence or absence of O2?

A

Facultative anaerobes; dispersed throughout test tube, but more towards the top

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Microaerophile

A

Low O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

True or false: all oral bacteria are towards the surface of the gums so they can be brushed away

A

False - some are anaerobes so they are found in pockets away from where you brush

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

When there is inflammation in a periodontal pocket, it is difficult for ____ to get in

A

saliva

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which anaerobic bacteria is associated with periodontal pockets?

A

Fusobacterium nucleatum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

F. nucleatum tolerates up to ___% oxygen

A

6%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Mesophiles are found between what temperatures?

A

25-40 celcius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Most medically important class of bacteria

A

Mesophiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Neutral pH

A

6.5-7.0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Acidophiles

A

Like acidic environment or can make acid; tolerate as low as 1.0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Halophiles

A

High osmolarity; found in brine or pickle, very salty environments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Important inorganic ion, often limited in supply

A

Iron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Bacterial iron sequestration protein

A

Siderophores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Human iron ions binding and transport proteins

A

Lactoferrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Where is lactoferrin found?

A

saliva, tears, bile, pancreas, breast milk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Lactoferrin is considered an _______

A

Antimicrobial (if we are taking the iron, bacteria can’t use it)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

How does siderophore sequester iron?

A

Secreted from bacteria, binds on to iron, then docks back onto the bacterial cell via receptor site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Major essential elements

A

CHONPS, K, Mg, Ca, Fe, Na, Cl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Minor essential elements

A

Zn, Mn, Mo, Se, Co, Cu, Ni, W

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What enzyme do bacteria secrete to break down sucrose?

A

Sucrase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What enzyme do bacteria secrete to break down lactose?

A

Lactase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

True or false: bacterial enzymes can remove glucose monomers from starch and glycogen

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What carbohydrates serve as carbon sources for bacteria?

A

Sucrose, lactose, starch and glycogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Main method of nutrient transport for bacteria

A

Active transport (ATP/proton pumps, permeases)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Active transport requires _____

A

energy (against conc gradient)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Growth phases of bacteria

A
  1. Lag
  2. Log
  3. Stationary
  4. Death/decline
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Lag phase

A

adaptation; getting ready to grow, feeling out the environment, figuring out what genes to turn on

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Log phase

A

rapid cell division when excess nutrients are available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

During which growth phase would penicillin be most effective?

A

Log phase (since new cell walls are being built)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Stationary phase

A

Balance on nutrients/toxins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Death/decline

A

nutrient deficit, toxin buildup

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What type of growth do we see when 2 or more substrates are present?

A

Biphasic/diauxic growth

50
Q

Two growth phases in biphasic growth

A
  1. primary growth
  2. secondary growth
    (separated by a short lag phase)
51
Q

Describe primary growth during biphasic growth

A

Breaks down sucrose to use glucose as preferred metabolite

52
Q

Why does a lag phase occur during biphasic growth?

A

1st substrate is depleted, cellular machinery makes alternate enzymes

53
Q

Secondary growth uses preferred or alternative metabolite?

A

Alternative

54
Q

What is broken down during secondary growth?

A

Lactose

55
Q

What occurs during binary fission?

A

DNA replication, septum formation

56
Q

Doubling time

A

Generation time; varies by species, can be minutes, hours, days

57
Q

Bacterial cell replication steps

A
  1. chromosome duplication
  2. mesosome formation - cytoplasmic membrane anchor for chromosome
  3. cell membrane involution
  4. cell wall completion using transpeptidase enzyme
58
Q

When there is high cell density of bacteria, they can exhibit group behavior as:

A

biofilm

59
Q

Biofilm may secrete:

A

Autoinducers –> can be more virulent, turn on more genes, more siderophores

60
Q

What triggers autoinduction of bacteria?

A

High numbers of bacterial cells

61
Q

Examples of group bacterial behavior responses

A

Operons or PAI (pathogen associated islands), proteases, virulence factors, siderophores

62
Q

How do bacteria know when to stop growing?

A

Starvation, buildup of toxic products triggers alarmones to stop growth

63
Q

Growth regulation methods

A

quorum sensing and autoinduction, changes in temp and pH, too much waste, depletion of food

64
Q

Bacteria use ____ to regulate peptidoglycan growth

A

D-amino acids
(signals growth inhibition and move to stationary phase)

65
Q

True or false: If bacteria sense that they need to slow down growth, they use L amino acids instead of D

A

False - they use D amino acids in place of L

66
Q

Bacteriostatic agent

A

Limits binary fission in stationary phase

67
Q

Bacteriocidal agent

A

Kills or destroys bacteria, leading to death phase

68
Q

Endospores are usually formed by gram ___ bacteria

A

Gram positive bacteria

69
Q

When do bacteria form endospores?

A

Nutrient deprivation

70
Q

How many spores are formed in sporylation?

A

1 spore

71
Q

Spores can lay dormant for:

A

Years

72
Q

Spores are resistant to:

A

Heat, dehydration, radiation, chemicals

73
Q

True or false: endospores are metabolically active

A

False - metabolically inert

74
Q

What occurs during sporulation?

A
  1. chromosome replication
  2. minimal cytoplasm
  3. cell membrane separation, peptidoglycan
  4. dipicolinic acid Ca2+ chelator (calcium dipicolinate
75
Q

Structure of endospore - name the layers

A
76
Q

Which bacteria are endospores commonly made by?

A

Bacillus, Clostridium

77
Q

Cortex of endospore is made of:

A

peptidoglycan, dipicolinic acid, calcium

78
Q

Growth assays methods

A
  1. wet mounts (slides)
  2. culture (plates)
  3. turbidity (solutions)
79
Q

Complex media contains:

A

carbon sources, water, various salts, source of nitrogen and amino acids

80
Q

Minimal media

A

Contains minimal materials for bacterial growth - one selecting agent (particular sugar or amino acid)

81
Q

Minimal media selects for:

A

Particular microbes

82
Q

Selective media

A

Growth/selection of select microorganisms

83
Q

Eosin-methylene blue agar (EMB) selective for

A

Gram - bacteria

84
Q

Mannitol Salt Agar (MSA) selective for

A

Gram+ bacteria

85
Q

Blood agar selective for

A

hemolytic Streptococcus

86
Q

Differential media

A

Distinguishes 1 type of microorganism from another growing on the same media

87
Q

Eosin-methylene blue agar (EMB) is differential for

A

Lactose and sucrose fermentation

88
Q

Mannitol Salt Agar is differential for

A

Mannitol fermentation

89
Q

MacConkey Agar differential for

A

Lactose fermentation

90
Q

On MCK agar, lactose fermenting colonies will be:

A

Pink

91
Q

MCK is selective for:

A

Gram - bacteria

92
Q

When ATP is hydrolyzed to form ADP + inorganic phosphate, how much energy is released?

A

30.5 kJ

93
Q

Where does cellular respiration occur in prokaryotes?

A

Cell membrane (no mitochondria)

94
Q

Catabolism substrates

A

sugars, proteins, lipids

95
Q

Anaerobic reactions

A

Fermentation - makes pyruvate, no TCA cycle. ATP and NADH products

96
Q

Aerobic reactions

A

TCA cycle, electron transport chain

97
Q

Glycolysis

A

Glucose to pyruvate catabolism

98
Q

EMP metabolic pathway

A

Almost universal, most bacteria, animals and plants

99
Q

Glycolysis via EMP pathway can occur in:

A

aerobic or anaerobic

100
Q

Glycolysis via EMP net end products

A

2 ATP, 2 pyruvate, 2 NADH

101
Q

ED pathway ATP net gain

A

1

102
Q

Pentose phosphate shunt net ATP

A

1

103
Q

Pentose Phosphate shunt involves:

A

hexose monophosphate shunt

104
Q

TCA cycle net ATP

A

2

105
Q

Fat input into TCA

A

Acetyl CoA

106
Q

Protein input into TCA

A
  1. Aspartic acid to oxaloacetate
  2. glutamic acid to a-ketoglutarate
107
Q

Pyruvate catabolism AA products

A

alanine, valine, leucine

108
Q

Oxaloacetate catabolism AA products

A

Lysine, methionine, threonine, isoleucine

109
Q

a-ketoglutarate catabolism AA products

A

lysine, proline, arginine

110
Q

Glyoxylate cycle

A

When glucose is unavailable and acetate is the only carbon source

111
Q

During glyoxylate cycle, bacteria convert _____ to _____ to make carbs

A

acetyl-coa to succinate

112
Q

Final electron acceptor is O2

A

aerobic respiration

113
Q

Final electron acceptor is an inorganic molecule, not O2

A

anaerobic respiration

114
Q

Oxidative phosphorylation

A

ETC generates energy through proton motive force (pH and charge difference); electrochemical gradient

115
Q

Aerobic respiration complete oxidation of glucose yields ___ ATP

A

30-38

116
Q

Anaerobic respiration total ATP

A

5-36 (depends on organism and final e acceptor)

117
Q

True or false: inorganic molecule as final e acceptor has greater redox potential than O2

A

False - less

118
Q

Fermentation final e acceptor is:

A

organic molecule, usually pyruvate

119
Q

____ can erode teeth enamels and cause caries

A

Lactic acid

120
Q

Hosts make ____ and ____ that can damage anaerobes

A

Free radical superoxide (O2-); hydrogen peroxide (h2o2)

121
Q

Microbes make enzymes to defend themselves against host metabolic products:

A
  1. superoxide dismutase - converts superoxide O2- to h2o2
  2. catalase enzyme converts h2o2 to o2
122
Q

Positive catalase

A

Bubbling in rxn