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Microbiology 2 Flashcards

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1
Q

Anabolism

A

biosynthesis reaction
taking smaller molecules and bringing them together with energy to create larger molecules
hydrolysis

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2
Q

Endergonic reaction

A

require more energy than they produce

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3
Q

Catabolism

A

break a large molecule down into smaller molecules to create a lot of energy
hydrolysis
an exergonic reaction
coupled to ATP synthesis

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4
Q

Enzyme characteristics

A

mostly proteins
catalysts(speed up a reaction)
not consumed by the reaction
lower activation energy

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5
Q

Components of holoenzyme (active enzyme)

A

Apoenzyme
Coenzymes
Cofactors

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6
Q

Apoenzyme

A

protein component of holoenzyme

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7
Q

Coenzymes

A

vitamin derived, organic, carbon containing

Accept electrons or donate electrons

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8
Q

Cofactors

A

low molecular weight

metal ions

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9
Q

Enzyme inhibition

A

both can bind reversibly or irreversibly (suicide inhibitor)

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10
Q

Competitive inhibition

A

occurs at the active site
sulfa drugs compete with PABA (para-aminobenzoic acid) at the active site of an enzyme that converts PABA to folic acid
Is a substrate analog (look a-like) that binds to the active site
Overcome by increasing substrate concentration

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11
Q

Non-competitive inhibitor

A

inhibits the reaction
do not compete with substrate at binding site
adheres to another binding site to distort the substrate binding site

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12
Q

Feedback inhibition or end product inhibition

A

Reversible, non-competitive inhibition

End product accumulates and inhibits the first enzyme of a metabolic pathway which shuts down the pathway

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13
Q

Reaction rate influences

A

temperature
pH
substrate concentration

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14
Q

Temperature effect on reaction rate

A

a catalyst up to a point then hinders the reaction by enzyme denaturation

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15
Q

pH effect on reaction rate

A

too high or too low causes denaturation of H+ compete with hydrogen and ionic bonds in an enzyme

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16
Q

Substrate concentration effect on reaction rate

A

saturation is when an active site of an enzyme always has a substrate bound
The more substrate there is, the faster the reaction until saturation occurs, and then there is a plateau

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17
Q

Oxidation

A 
loss of electrons
gains oxygen
loses hydrogen
loss of energy
exothermic/exergonic reaction
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18
Q

Two key players to the oxidation of organic compounds

A

Dehydrogenases-enzymes

Coenzymes

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19
Q

Coenzymes

A

vitamin derived organic molecules

 a. Nicotinamide adenine dinucleotide (NAD)
 b. Flavinadenine dinucleotide (FAD)
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20
Q

Reduction

A 
gain of electrons
loss of oxygen
gain of hydrogen
gain of energy
endothermic/endergonic  reaction
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21
Q

Redox

A

combination of oxidation and reduction reactions they are used simultaneously

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22
Q

Substrate level phosphorylation

A

ATP is generated when a phosphate is transferred from an organic compound to ADP

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23
Q

Oxidative phosphorylation

A

uses chemiosmosis and electron transport chain to phosphorylate ADP

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24
Q

Total ATP generated

A

38 ATP per glucose molecule

NAD produces more ATP than FAD

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25
Q

Fat catabolism

A

a fat is a lipid consisting of glycerol + 3 fatty acids-can be broken into this using a lipase
Krebs cycle is used

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26
Q

Protein catabolism

A

uses the Krebs cycle

proteins are too large to pass through plasma membranes and must be broken down first

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27
Q

Deamination

A

Used in protein catabolism

can use protease to break protein into individual amino acids that are able to enter the Krebs cycle

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28
Q

Metabolism

A

the sum of all chemical reactions occurring within an organism
balances energy
two classes of reactions, gaining or losing energy

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29
Q

Fermentation

A

an anaerobic pathway
generally does not use oxygen
does not use Krebs cycle
electron transport chain
cannot occur in presence of O2
can still perform glycolysis to get 2 ATP, 2 NADH NAD+
organic molecule is the final electron acceptor-is pyruvate or a derivative of pyruvate

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30
Q

Homeolactic acid fermentation

A

one glucose molecule is converted to two molecules of lactic acid

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31
Q

Alcohol fermentation/ethanol fermentation

A

sugars such as glucose, fructose, and sucrose are converted into cellular energy and produce ethanol and carbon dioxide as metabolic waste products

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32
Q

Lactic acid fermentation

A

glucose, fructose, and sucrose are converted into cellular energy and the metabolite lactate
Lactate dehydrogenase catalyzes the conversion of pyruvate and lactate with concomitant conversion of NADH and NAD+

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33
Q

Nutritional factors effecting the growth of bacteria

A 
carbon
energy
sulfur
nitrogen
phosphorus
trace elements
oxygen
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34
Q

Carbon source

A

cell needs external carbon source
this makes up 50% of the cell’s dry weight
users can be heterotrophic or autotrophic bacteria

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35
Q

Heterotrophic bacteria carbon use

A

carbon comes from organic compounds like lipids, proteins and carbohydrates

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36
Q

Autotrophic bacteria carbon use

A

they can use inorganic carbon like from carbon dioxide

they can fix O2 from the atmosphere

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37
Q

Uses for carbon

A

required for all organic compounds

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38
Q

Categories of energy users

A

phototrophic bacteria

chemotrophic bacteria

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39
Q

Phototrophic bacteria

A

organisms that use light

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40
Q

Chemotrophic bacteria

A

organisms that get energy from the oxidation of organic compounds and inorganic chemicals

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41
Q

Energy uses

A

metabolism, all cellular processes

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42
Q

Sulfur sources

A 
sulfate ion (inorganic)
proteins that have sulfur containing amino acids (organic)
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43
Q

Sulfur uses

A

sulfur containing amino acids for protein synthesis

thymine and biotin synthesis

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44
Q

Nitrogen sources

A

organic: proteins (contain amino acids), amino acid is denatured into NH2
inorganic: nitrogen gas (N2), NH4+, NO3

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45
Q

Nitrogen uses

A

required for synthesis of amino acids
synthesis of nitrogenous bases in DNA
synthesis of amino sugars—NAN, NAG

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46
Q

Phosphorus source

A

inorganic only—PO4 3-

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47
Q

Phosphorus uses

A

make ATP
nucleic acid backbone—synthesis of nucleotides
synthesis of phospholipids

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48
Q

Trace elements sources

A

inorganic only

ex: iron, copper, zinc, magnesium

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49
Q

Trace elements uses

A

cofactor for enzymatic reaction
required for synthesis of B12
bacteria have iron containing cytochrome in the electron transport chain

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50
Q

Superoxide dismutase

A

works of superoxide free radical to eliminate toxic forms of oxygen

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51
Q

Catalase

A

breaks down hydrogen peroxide to water and hydrogen gas
if bubbles form, catalase is present
2H2O2  2H2O + O2

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52
Q

Peroxidase

A

breaks down hydrogen peroxide
no O2 gas is produced
H2O2 + 2H+ 2H2O

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53
Q

Obligate anerobe

A

does not have superoxide dismutase, catalase or peroxidase

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54
Q

Facultative anerobe or aerobe

A

have superoxide dismutase, catalase and peroxidase

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55
Q

Physical factors affecting bacterial growth

A 
some enzymes can adapt to be able to live in extreme environments like high salt, high heat and high or low pH
temperature
pH
oxygen requirements
osmotic pressure
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56
Q

Temperature affect on bacterial growth

A

there is an ideal temperature with steep drops on either end

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57
Q

Psychophile

A

optimal growth at 15C

ex: organisms that grow deep in the ocean

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58
Q

Mesophile

A

optimal temp = 37C (25-40 is ok too)

is most common type of microbe

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59
Q

Thermophile

A

heat loving microbes
optimal temp=50-60C
ex: microbes that grow in a compost heap

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60
Q

Neutrophiles

A

like a neutral pH

most bacteria like pH 6.5-7.5

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61
Q

Acidophiles

A

like pH 6 and below

ex: helicobacter pylori can grow at pH 2

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62
Q

Alkeliphiles

A

can grow at pH 7-11.5

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63
Q

Non-halophiles

A

grow at normal sodium levels

cannot survive high salt concentrations

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64
Q

Moderate/facultative halophiles

A

will grow at concentrations of 2-15% salt
doesn’t require high salt but can grow at high salt
Ex: pseudomonas, organisms involved in bioremediation (cleaning oil spills)

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65
Q

Obligate halophiles

A

require high salt concentration for growth

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66
Q

Extreme halophiles

A

require even higher salt concentration, > 15%

Ex: organisms from the dead sea grow at salt concentrations of 30%

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67
Q

Defined culture media

A

when we need to know everything that is in the growth media
we don’t use this in our labs
chemically defined is for research purposes only

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68
Q

Glucose culture media

A

carbon and energy source

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69
Q

Ammonium phosphate

A

nitrogen source and phosphate source

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70
Q

MgCl2

A

magnesium chloride provides trace metals

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71
Q

Sodium chloride

A

provides osmotic balance

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72
Q

K2HPO4

A

a buffer

can accept or donate protons to keep pH neutral

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73
Q

Fastidious

A

an organism that requires one or more growth factors (an essential organic compound that the bacterium cannot synthesize)

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74
Q

Complex culture media

A

chemically undefined
easier to grow than defined media
chemical compound of soy, beef, peptones or yeast extract-can vary

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75
Q

Agar

A

isolated from seaweed which can vary from batch to batch

any solid media is chemically undefined

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76
Q

Peptones

A

partially digested proteins that are easier for the bacteria to take up
if we add peptones, we add lots of different amino acids

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77
Q

TSA

A

tryptic digest of soy

trypsin is a protease, cleaves/digests soy proteins

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78
Q

Beef extract

A

adding this adds amino acids and vitamins

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79
Q

Selective media

A

ex: PEA will suppress the growth of certain microbes

suppresses growth of G- and gives G+ a chance to grow

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80
Q

Differential media

A

ex: Chrom agar E, causes pathogens to have different colors allowing for identification
ex: MSA, manitol salt agar, is also a selective media, has a pH indicator in it (phenol red), media is red at pH>6.8, media is yellow at pH <6.8, manitol ferments to change pH

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81
Q

Enrichment media

A

gives extra nutrition to fastidious organisms

ex: blood agar, does not suppress growth

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82
Q

Gas pak

A

has packet that when activated removes all O2 and creates H2 with it

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83
Q

Candle jar method

A

reduces O2 concentration

increases CO2 concentration

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84
Q

Binary fission

A

bacteria double in size before they split
is cell division in prokaryotes
is analogous to mitosis in eukaryotes
is asexual

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85
Q

Binary fission steps

A

i. DNA synthesis and elongation of the cell
ii. Cell begins to elongate
iii. Cross wall forms –> separates the 2 sets of chromosomes
iv. Binary fission/cell separates into 2 cells, all cells are clones of each other

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86
Q

Bacterial growth curve

A

lag phase
log phase
stationary phase
death phase

87
Q

Lag phase

A

cells do not immediately divide
is not a resting phase
active metabolism occurs, “active metabolism”

88
Q

Log phase

A 
period of active growth
exponential growth
no nutrients are limiting or cell’s won’t divide as quickly
optimal conditions for cell growth
rapid and constant growth rate
can determine doubling time/growth rate
89
Q

Log phase examples

A

ex: E. coli doubles every 20 min
Bacillus sterothermophilis doubles every 6 min, is a thermophile, likes 55C
Mycobacterium teburculous doubles every 360 min

90
Q

Stationary phase

A

stabilization of growth
# of cells dividing = # of cells dying
usually begins when key nutrient is depleted
pH may have dropped
accumulation of toxic byproducts of metabolism and harmful changes to pH

91
Q

Death phase

A

lacks all nutrients needed for growth
# of deaths far exceeds # of new cells
media is totally exhausted
environment is toxic

92
Q

Measuring bacterial growth directly

A

standard plate count
direct microscopic count
filtration

93
Q

Direct microscopic count advantage

A

no waiting period
can count cells immediately
no incubation period

94
Q

Direct microscopic count disadvantage

A

can’t tell if cells are dead or alive so you count both dead and living bacteria

95
Q

Petroff-Hauser cell counter

A

is a microscope slide with a fixed cover slip grid on it

can count bacteria in certain # of squares and multiply by the conversion factor

96
Q

Filtration

A

used when bacterial concentration is very small, <= 1 bacteria/mL

97
Q

Filtration application

A

water testing for possible fecal contamination

98
Q

Filtration steps

A

1: 100ml H2O sample and filter it
2: transfer filter to pad in petri dish soaked in nutrient broth
3: grow overnight
4: count # of bacteria and report # of bacteria/100mL

99
Q

Measuring bacterial growth indirectly

A

turbidity/spectrophotometric
cell mass
metabolic activity

100
Q

Turbidity/spectrophotometric

A

absorbance or transmittance readings can be taken

measure the turbidity to indicate cell growth

101
Q

Turbidity/spectrophotometric disadvantage

A

bacteria must be growing at high numbers to be turbid enough to read

102
Q

Cell mass

A

a certain volume of culture would be filtered

dried and weighed to get # of bacteria/mL

103
Q

Metabolic activity

A

measure O2 consumed or measure amount of acid produced

104
Q

Disinfection

A

reduction in # of bacteria

105
Q

Disinfectant

A

chemical agent that results in a reduction in # of bacteria

106
Q

Antiseptic

A

disinfectant that can be used on the skin

107
Q

Sterilization

A

removal of all pathogens including those with endospores

108
Q

Filter paper

A

discs soaked in chemical agents placed on a lawn of bacteria
create a zone of inhibition
the widest zones do not necessarily indicate the most effective chemical agent

109
Q

Phenol coefficient

A

used by Lister to sterilize or used as a standard to compare other disinfectants
coefficient of 1 in other disinfectants means it is as effective as phenol
> 1 = better, < 1 =worse

110
Q

Phenol mechanisms of action

A

protein damage/denaturation
membrane damage
damage to nucleic acids/chemical groups

111
Q

Protein damage/ denaturation

A

ex- heat denaturation
hydrolysis (breaks bonds)-strong acids and bases
oxidation (strip electrons)
attachment of atoms or chemical groups

112
Q

Bactericidal

A

kills the microbe

113
Q

Bacteriostatic

A

inhibits the growth of the microbe

114
Q

Membrane damage

A

will kill the cell because cell contents will leak out

115
Q

Phenol coefficient dilutions use

A

dilute phenol and dilute the chemical to compare to phenol

make 2 dilutions

116
Q

Phenol coefficient dilutions steps

A
  1. Add standard amount of bacteria to each dilution tube
  2. Take samples out of each tube after a set amount of time and plate onto fresh media, let them grow 12-48 hours
  3. You are looking for the highest dilution (lowest concentration) that killed the bacteria
117
Q

Disinfectant types

A 
surfactants
heavy metals
halogens
alcohols
phenolics
oxidizers
alkylating agents
118
Q

Surfactants

A

decrease surface tension, effect the cell membrane

ex: soaps/detergents, anionic sanitizers, quaternary ammonium compounds–none of these are effective against spores

119
Q

Soaps/detergents

A

good de-germing agents
don’t kill bacteria very well
they mechanically remove bacteria, oil and debris

120
Q

Anionic sanatizers

A

are negatively charged
they are less effective on bacteria that quaternary ammonium compounds(which are cations) because bacteria are also negatively charged and are repelled
used to sanitize utensils and equipment

121
Q

Quaternary ammonium compounds

A

have a valence of 4, much better surfactants, especially against G+ bacteria

122
Q

Quaternary ammonium compounds mechanism of action

A

causes changes to cell permeability, effects the plasma membrane of the cell

123
Q

Heavy metals

A

can be used as a disinfectant

ex-silver, copper, zinc, mercury

124
Q

Heavy metals mechanism of action

A

protein denaturation
can be biocidal (kill bacteria)
metals can combine with sulfhydryl groups on proteins and denature them

125
Q

Halogens

A

Iodine

Chlorine

126
Q

Iodine

A

good antiseptic

effective on G+, G- and some spores

127
Q

Iodine mechanism of action

A

alters membrane permeability and disrupts protein synthesis

128
Q

Betadine

A

iodine combined with an organic molecule (iodophore)

129
Q

Chlorine

A

a good disinfectant

effective against G+, G- and some spores

130
Q

Mechanism of action of bleach

A

denature proteins

131
Q

Hypochlorious acid

A

Cl2+H2O -> <-H+Cl-+HOCl

132
Q

Hypochlorite ion

A

has strong oxidizing agent

HOCl -> <- H+ +OCl-

133
Q

Alcohols

A 
denature proteins
disrupt membranes
needs water to denature proteins
100% alcohol is less effective than 70% alcohol
is not a good antiseptic
134
Q

Phenolics

A

derivatives of phenol

135
Q

Bisphenols

A 
have 2 rings
effective against G+ and mycobacterium
ex: triclosan
can disrupt lipid wall of mycobacteria
used in disinfection of organic compounds like pus, saliva, vomit and feces
136
Q

Oxidizers

A

H2O2 (hydrogen peroxide) is an oxidizing agent
is not a good antiseptic because our cells contain catalase
is a good disinfectant at high concentration and can be effective against spores

137
Q

Oxidizers method of action

A

oxidation

H2O2 ->O2 + H2O

138
Q

Alkylating agents

A

Formaldehyde

Glutoraldehide

139
Q

Formaldehyde

A

used in vaccines to inactivate bacteria and viruses

140
Q

Glutoraldehide

A

disinfectant for hospital equipment
kills spores but takes 3-10 hours to do it so it is not a stearalizing agent (must kill spores in <30min)
bactericidal, virucidal, tuberuclocidal, sporucidal (under the right conditions)

141
Q

Physical antimicrobial agents

A 
heat application
refrigeration
freezing
desiccation
freeze drying
osmotic control
radiation
filtration
142
Q

Heat application

A

dry heat
autoclave
pasteurization

143
Q

Dry heat

A

used when we flame our loops

denaturing proteins through oxidation by incineration which achieves sterility

144
Q

Autoclave

A 
moist heat under pressure
achieves sterility
kills spores
reaches temperatures over 100C
can go above boiling point by adding pressure
145
Q

Autoclave specifications

A

15lbs pressure, 121C for 20 min

146
Q

Pasteurization

A

kill pathogens
does not sterilize
want to kill mycobacteria and salmonella
increases shelf life

147
Q

Phosphate test

A

used to determine if pasteurization has worked

should cause phosphatase to be inactivated

148
Q

High temperature/low time pasteurization method

A

is the most common method
flash method
71.6C for 15 sec

149
Q

Holding method for pasteurization

A

62.9C for 30 min

150
Q

Sterilized milk

A

ultra-high temperature treatment
140C for 4 sec
milk can then be stored at room temperature
this can cause loss of flavor

151
Q

Referigeration

A

does not kill bacteria
bacteriostatic effect
slowing metabolic rate so they don’t produce toxins

152
Q

Freezing

A

not killing bacteria

bacteria are dormant

153
Q

Desiccation

A

removal of water which is required for metabolic processes
this stops metabolism
does not kill bacteria
bacteria can remain viable and desiccated state for years
when we re-hydrate, bacteria will grow and divide

154
Q

Freeze drying

A

aka lypohilization
a good way to preserve microbes
Mycobacterium tuberculosis can remain viable in this state for several months

155
Q

Osmotic control

A

hypertonic environment is when solute concentration is higher outside the cell
water moves out of the cell
this causes the cell membrane to shrivel which is called plasmolysis

156
Q

Radation

A

UV radiation

Ionizing radiation

157
Q

UV radiation

A

can cause thymine dimers
UVB absorbed by nitrogenous bases
thymine dimers can inhibit correct replication of DNA

158
Q

UV radiation, mechanisms of repair

A

light repair

dark repair

159
Q

Light repair

A

light activates photolysis which breaks bond between thymine dimers

160
Q

Dark repair

A

can occur with or without light

several enzymes repair the dimer

161
Q

Endonuclease

A

can cut into DNA and repair around the site of mutation

162
Q

Exonuclease

A

chews nicked part from the end to remove it

163
Q

DNA polymerase and DNA ligase

A

required for light and dark repair

164
Q

Ionizing radiation

A

radioactive element emitting gamma rays, X rays or electron beams, they dislodge electrons to create ions
To dislodge electrons from H2O (ionize it), we form a toxic form of O2 (hydroxyl radical which damages DNA and cell components)

165
Q

Filtration

A

can achieve sterility with membrane filtration
0.22 or 0.45 um filter can trap bacteria on the surface of the filter because bacteria are larger than 0.22um
Viruses can still get through unless you use 0.1 um filter pore size which will block viruses

166
Q

Chemotherapeutic agents

A

antibiotics
synthetic drugs
semi-synthetic drugs

167
Q

Antibiotics

A

microbe made

natural anti-microbial

168
Q

Synthetic drugs

A

man made chemicals

169
Q

Semi-synthetic drugs

A

can be produced by microbes if microbes are fed a synthetic precursor

170
Q

Properties of antibicrobial agents

A

selective toxicity

spectrum of activity

171
Q

Selective toxicity

A

want it to be selectively harmful and toxic to bacteria but not to us

172
Q

Chemotherapeutic index

A

maximum tolerable dose of antibiotic per kg of body weight divided by minimum effective dose per kg of body weight, we want this number to be high

173
Q

Spectrum of activity

A

Broad

Narrow

174
Q

Broad spectrum of activity

A

works on a large range of taxanomic groups

175
Q

Drug mechanisms of action

A 
Inhibition of cell wall synthesis
Disruption of cell membrane function
Inhibition of protein synthesis
Inhibition of nucleic acid synthesis
Antimetabolites
176
Q

Side effects of broad spectrum antibiotics

A

Disruption of micro flora

Can lead to super infection

177
Q

Resistance

A

genetic
non-genetic
plasmid borne

178
Q

Non-genetic

A

an organism evades antibiotic based on its location

179
Q

Genetic

A

resistance due to mutations

180
Q

Plasmid borne

A

extrachromosal DNA, contain R plasmids that can carry 6-7 genes that have resistance to antibiotics

181
Q

Superbugs

A

resistant to several antibiotics, multidrug resistance

182
Q

Mechanisms of drug resistance

A 
Mutations in target molecules
Alterations in membrane permeability
Enzyme development
Enzyme activity changes
Alterations of metabolic pathways
183
Q

Alterations in membrane permeability

A

if there is a change in the DNA that effects cell wall permeability, could affect cell wall protein causing the cell to no longer be permeable to the antibiotic

184
Q

Enzyme activity changes

A

could develop enzyme with a higher affinity for another substance
Ex: PABA when treated with sulfonamide

185
Q

Alterations of metabolic pathways

A

normally, bacterium creates its own folic acid but pathway may have been altered and is unable to use readymade folic acid

186
Q

Determining microbial sensitivities

A

disk diffusion or Kirby-Bauer method

dilution method

187
Q

Disk diffusion or Kirby-Bauer method

A

Kirby Bauer assay: there are standard measurements for the zone diameter, bigger zone does not necessarially indicate the best treatment, the different treatments are then labeled sensitive, moderately sensitive or resistant

188
Q

Dilution method

A

Minimal inhibitory concentration (MIC)

Minimal bacterial concentration (MBC)

189
Q

minimal inhibitory concentration (MIC)

A

use dish with many wells and increase dilution, looking for the highest dilution where you do not see any growth

190
Q

Minimal bacterial concentration (MBC)

A

highest dilution that kills the bacteria

191
Q

Stages of cellular respiration

A

Glycolysis
Krebs cycle
Electron transport chain

192
Q

Glycolysis location

A

takes place in the cytoplasm of the cell

193
Q

Glycolysis

A

anerobic metabolism
oxidizes glucose
NAD+ are reduced to NADH

194
Q

Glycolysis summary

A

Input: 2 ATP
Output: 4 ATP
Net: 2 ATP, 2 NADH, 2 pyruvate

195
Q

Krebs cycle location-Eukaryotes

A

takes place in the inner space of the mitochondria

196
Q

Krebs cycle pre-step

A

the oxidation of pyruvate, this must occur for pyruvate to enter the Krebs cycle

197
Q

Krebs cycle location-Prokaryotes

A

occurs in the cytoplasm of the cell

198
Q

Glycolysis location

A

takes place in the cytoplasm of the cell

199
Q

Glycolysis

A

anerobic metabolism
oxidizes glucose
NAD+ are reduced to NADH

200
Q

Glycolysis summary

A

Input: 2 ATP
Output: 4 ATP
Net: 2 ATP, 2 NADH, 2 pyruvate

201
Q

Krebs cycle location

A

takes place in the inner space of the mitochondria

202
Q

Krebs cycle pre-step

A

the oxidation of pyruvate, this must occur for pyruvate to enter the Krebs cycle

203
Q

Classes of electron carriers (electron transport chain)

A

cytochromes
flavoproteins
ubiquinomes of coenzyme Q

204
Q

Krebs cycle

A

aerobic metabolism
uses substrate level phosphorylation
is a highly oxidative pathway
GTP preforms decarboxylation

205
Q

Krebs cycle summary

A

Input: 0 ATP
Output: 2 ATP, 2 FADH2, 8 NADH (including prep-step)
Pre-step makes 2 NADH

206
Q

Chemiosmosis/electron transport chain location

A

occurs in the cellular membrane

207
Q

Chemiosmosis/ electron transport chain

A

makes the most ATP
3rd stage of respirtation
electrons are passes from coenzymes to electron carriers which releases energy to make ATP

208
Q

Chemiosmosis/ electron transport chain summary

A

Input: 10 NADH, 2 FADH2
Output: 30 ATP, 4 ATP (respectively)

209
Q

Classes of electron carriers (electron transport chain)

A

cytochromes
flavoproteins
ubiquinomes of coenzyme Q

210
Q

Cytochromes

A

contain a heme group (iron), all need to be able to exit at the oxidized and reduced state

211
Q

Flavoproteins

A

are a co-enzyme

212
Q

Ubiquinones or coenzyme Q

A

non protein carriers

213
Q

Beta oxidation

A

the process where fatty acid molecules are broken down in the mitochondria to generate acetyl-coA, which enters the krebs cycle

Microbiology (6 decks)

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