Exam 2 Flashcards
(187 cards)
1
Q
Disinfection of living tissue using a chemical agent. Safe on skin, could be alcohol, hydrogen peroxide
A
Antisepsis
2
Q
Reduce the number of pathogens to meet public health standards
A
Sanitization
3
Q
Use of heat to reduce the # of spoilage organisms in food or beverages
A
Pasteruization
4
Q
3 modes of actions of microbrial control agents? How do they kill microbes?
A
- Alters membrane permeability
- Denatures proteins by disrupting 3d structure so that proteins cannot function
- Damages nucleic acids: DNA + RNA
5
Q
Destroying microbes on inanimate objects or surfaces
A
Disinfecting
6
Q
Killing any and all microbes
A
Sterilization
7
Q
What is that action to bacteria and cells from radiation?
A
Damages nucleic acids
8
Q
3 examples of using heat to denature protein + kill
A
- Bacticinerator
- Dry heat/hot air
- Moist heat
9
Q
Examples of moist heat
A
Holding method (62.9 C for 30 min)
Flash method (71.6 C for 15 sec)
Ultra high temp method (140 C for 3 sec)
10
Q
What type of heat is from an autoclave? 121 C at 15 lbs of pressure for 15 min
A
Moist heat + pressure
11
Q
What are the two type of radiation?
A
Ionizing and non-ionizing
12
Q
Examples of ionizing radiation and what it can be used on
A
-Gamma + X-rays
-Can preserve food
-Can be used on protein-based drugs
-Vaccines
-Plastic instruments
13
Q
Examples of non-ionizing radiation and what is can be used on
A
-UV light (mismatch nucleotides)
-Used in OR, Morgues, and Labs
14
Q
What is the action of osmosis on bacteria?
A
Shrivels or burst the microbe
High sure or salt water osmose OUT of the cell
15
Q
What is the action of filtration on bacteria?
A
Pores in filter that trap microbes.
-Surgical maskm HEPA filters in heating + AC
-Some drugs get filtered
16
Q
What is the action of cold on bacteria?
A
Slows growth, metabolism, and reproduction
17
Q
Lyothalization
A
Removes water under a vaccum and decreases metabolism in bacteria
18
Q
Action of of Phenols + Phenol derivatives
A
Alters membrane permeability and denatures proteins
19
Q
Phenol…
A
Poor solubility
Is caustic to skin
Can damage CNS
Stinks
20
Q
Action of aldehydes
A
Denatures proteins
21
Q
Types of aldehydes
A
Formaldehyde
Formalin
Glutaraldehyde
OPA
22
Q
What is the action of surfactants?
A
Mechanical removal of microbes
23
Q
The action of hydrogren peroxide?
A
Free radicals -OH are toxic and damage cells by stealing electrons
24
Q
Alexander Flemming
A
Left streak plate open + mold got into it.
Antibiotics were discovered
25
Define antibiotic
A substance naturally produced by a few bacterial and fungal species that inhibits or kills bacteria
26
Antibiotics only kill what?
Bacteria
27
Five target of antibiotics
1. Bacterial cell wall
2. Disrupting/disorganizing membranes
3. Nucleic acid synthesis
4. Block protein synthesis
5. Metabolic pathways
28
What did we use before antibiotics?
Enema, blood-curdling ice baths, deadly starvation, bloodletting
29
Who discovered antibiotics?
Alexander Flemming
30
Bacterial DNA is super-coiled via an enzyme called _________
Gyrase
31
What is the shape of the bacterial chromosome?
Circle
32
How many chromosomes do bacteria usually have?
2
33
A plasmid carries essential information
False
34
Plasmids have to replicate when the bacterial chromosome replicates
False, it replicates independently
35
A small, circular DNA separate from the bacterial DNA is a(n)
Plasmid
36
The monomer of nucleic acids
Nucleotides
37
Nucleotides are composed of
sugar, a phosphate group, and a nitrogenous base.
38
The nitrogenous bases in DNA are
Adenine
Thymine
Cytosine
Guanine
39
How many strands does DNA contain?
2
40
The building block of nucleic acids is glycerol and fatty acids
False (nucleotides)
41
The specificity of DNA is in the
Order of the nucleotides
42
The building block or monomer of DNA and RNA is
Nucelotides
43
The sugar in DNA is
Deoxyribose
44
A _ is a specific sequence of nucleotides that codes for a protein or RNA
Gene
45
DNA is a nucleic acid
True
46
A _____ is the entire genetic complement of a cell or virus
Genome
47
The sugar in RNA is
Ribose
48
Nitrogenous bases in RNA are
Adenine
Uracil
Cytosine
Guanine
49
What are the three types of RNA?
Transfer, messenger, and ribosomal RNA
50
How many strands does RNA have?
1
51
One strand (the 5’ or five prime strand) has
A terminal phosphate group
52
The other strand (the 3’ or three prime strand) has a
Terminal hydroxyl group
53
Acts as a go between between DNA and protein
Messenger (mRNA)
54
Ribosomes along with proteins are what RNA is made of
Ribosomal (rRNA)
55
Transfers amino acids
Transfer (tRNA)
56
An enzyme called ________ unwinds and unzips the DNA at the ori site
Helicase
57
_______ adds complementary nucleoties in the 5' > 3' direction
DNA Polymerase
58
The strand that is replicated continuously is called
The leading strand
59
The DNA strand that's replicated in fragments is known as
Okazaki fragments
60
What are Okazaki fragments knitted(seal) together by?
DNA Ligase
61
What direction does DNA polymerase make strands in?
5' > 3'
62
The process of DNA being converted to mRNA is known as
Transcription
63
The process of mRNA being converted to protein is known as
Translation
64
moves along the DNA strand that is serving as the template and adds complementary nucleotides and builds the mRNA strand (transcription)
RNA Polymerase
65
Transcription occurs in ______ of prokaryotic cell
Cytoplasm
66
Transcription takes place in the ______ in eukaryotic cell
Nucleus
67
In transcription _____ is transcribed into _____
DNA, mRNA
68
How many DNA strands serve as a template in transcription?
1
69
Action of alcohol on bacteria
Damages membranes and denatures proteins
70
The action of gaseous sterilizer on bacteria
Denatures protein
71
Action of hydrogen peroxide on bacteria
Free radicals are toxic and damage cells by stealing electrons
72
Water disinfection
Ozone
73
Halogens actions on bacteria
Denatures proteins
74
Heavy metals on bacteria
Denatures proteins
75
What does drying do to bacteria?
Decreases metabolism
76
List what chemicals sterilize
Aldehydes, Gaseous Sterilizers, and Chlorine Dioxide by denaturing proteins
77
Contribution of Paul Ehrlich
Synthesized compound salvarson 606 which is an antimicrobial drug. Gave this to syphillis patients. All his compounds contained phenol and arsenic
78
Contribution of Gerhard Domagk
Created antimocrobial drug in form of red dye called Prontosil. Used against strep, staph, mice
79
Contribution of Alexander Flemming
Did research on staphylococcus and streak plate became contaminated. ID'd mold as Penicillium and tried to isolate Penicillin
80
Contribution of Howard Florey + Ernstchain
Chemists that isolated penicillin and was used to treat people very quickly
81
Contribution of Selman Waksman
Soil microbiologist that discovered 20 diff antibiotics. First to call "Antibiotics" what they're called now
82
5 targets of antibiotics
1. Bacterial CELL WALL
2. Disrupt MEMBRANES
3. NUCLEIC-ACID synthesis
4. Block PROTEIN synthesis
5. METABOLIC pathways
83
Targets of bacterias effectiveness on Gram+ and Gram -: Bacterial cell wall
Effective against GRAM +
Not effective against Gram - (outer membrane protects underlying cell wall)
84
Targets of bacterias effectiveness on Gram+ and Gram -: Bacterial cell wall
Effective against GRAM +
Not effective against Gram - (outer membrane protects underlying cell wall)
85
Targets of bacterias effectiveness on Gram+ and Gram -: Disrupts membranes
Effective against GRAM - (disrupts outer membrane)
Not effective against Gram + (thick cell wall blocks access to cell membrane)
86
Targets of bacterias effectiveness on Gram+ and Gram -: Nucleic-acid synthesis
Effective against both + and - gram baceria
87
How do bacteria resist antibiotics?
1. Produce ENZYMES that destory antib.
2. Decrease entry of antibiotic alter MEMBRANE PERMEABILITY
3. PUMPS OUT
4. Alter TARGET SITE
5. Changes METABOLIC PATHWAYS
88
How do bacteria ACQUIRE resistance?
Mutation
Conjugation
Transduction
Transformation
89
The process of DNA being converted to mRNA is known as
transcription
90
The process of mRNA being converted to protein is known as
translation
91
Where does TRANSLATION occur?
Cytoplasm in both euk. and prok.
92
What are ribosomes?
Site of protein synthesis
93
Prokaryotes have what kind of ribosomes?
70s
94
Eukaryotes have what kind of ribosomes?
80s
95
Where does TRANSCRIPTION occur in prokaryotes?
Cytoplasm
96
Where does TRANSCRIPTION occur in eukaryotes?
Nucleus
97
The process of converting DNA to mRNA
Transcription
98
A ______ is 3 nucleotides on mRNA
Codon
99
Each codon specifies an
amino acid
100
More than one codon encodes for the same amino acid
True
101
The genetic code is redundant or degenerate. This means that
More than one codon encodes for the same amino acid
102
Can be used to cut a human gene out human DNA.
Restriction enzymes
103
We then insert the human gene into the plasmid and knit the DNA together using
DNA Ligase
104
Is used to produce human proteins including insulin, clotting factors, interferon, and growth hormone.
Recombinant DNA technology
105
Since the two DNA strands run __________the strands will have to be copied slightly differently.
Anti-parallel
106
DNA replication then proceeds _________
around the circular bacterial chromosome
Bi-laterally/directionally
107
Chemical and physical agents that control the growth of microorganisms that have an action of denaturing proteins include all the following EXCEPT
Radiation
Hydrogen peroxide
Cold
Drying
Osmosis
Filtration
Surfactants
108
Flow of information is a cell proceeds from DNA to Protein to mRNA
False
109
Which of the following is NOT an action of chemical or physical agents that control the growth of microorganisms?
Damage nucleic acids
Alteration of membrane permeability
Block protein synthesis
Damage nucleic acids
Block protein synthesis
110
Which of the following is an action of a narrow spectrum antibiotic?
inhibition of nucleic acid synthesis
Inhibition of essential metabolites
Inhibition of protein synthesis
inhibition of cell wall synthesis
inhibition of cell wall synthesis
111
Hydrogen peroxide is ONLY effective against obligate aerobes
False
112
The DNA samples are digested with a restriction enzyme this is called
RFLP or restriction fragment length polymorphism.
112
The DNA samples are digested with a restriction enzyme this is called
RFLP or Restriction Fragment Length Polymorphism.
113
Polymerase chain reaction (PCR) is used to
multiply DNA
114
What are the 5 targets of antibiotics?
1. Protein synthesis
2. Nucleic acid synthesis
3. Cell wall
4. Membrane
5. Metabolism
115
4 ways antibiotics acquire resistance
Mutation
Conjugation
Transduction
Transformation
116
5 ways bacteria resist antibiotics
1. Pump antibiotic out
2. Change target site
3. Produce enzymes
4. Decrease entry (membrane)
5. Change metabolic pathway
117
Contribution of Paul Ehrlich
Created Compound Salvarson 606 which was an antimicrobial drug
Created magic bullet
117
Contribution of Paul Ehrlich
Created Compound Salvarson 606 which was an antimicrobial drug
Created magic bullet
118
Contribution of Gerhard Domagk
Created a synthetic antimicrobial drug called Prontosil
119
Contribution of Alexander Fleming
Left streak plate + mold got into it. Mold was penicillium. Antibiotics were discovered
120
Contribution of Howard, Florey, and Ernst Chain
Were able to isolate penicillium
Made penicillin readily available quickly
121
Selman Waksman
Soil microbiologist, found 20 different antibiotics
122
Section of DNA that contains one or more structural genes along with a regulatory gene that controls transcription of the structural gene(s).
Operon
123
The ________ gene of an operon is always transcribed + translated
Regulatory Gene
124
The product of the regulatory gene is a
Repressor protein (can be active or inactive)
125
What happens when repressor protein binds to operator site?
Blocks RNA polymerase so structural genes are not transcribed and translated
126
Order of sections in an operon
**DNA** Regulatory gene [promoter, operator, structural genes]
127
What happens when the repressor protein binds to the operator site?
When it doesn't bind?
Blocks RNA polymerase so structural genes are not transcribed and translated
RNA polymerase can transcribe + translate structural genes
128
Environmental structure is in the environment and inactivates repressor protein by attaching to it and structural genes will be made
Repressor protein is always active when structure is not in the environment
Lactose Operon "induce operon"
128
Environmental structure activates Repressor protein by attaching to it to block transcription and translation of structural genes
When environmental structure isn’t in the environment, Repressor protein is inactive and the structure is naturally made in our body
Tryptophan Operon
129
When there is no tryptophan in the environment, the repressor protein is...
Inactive so RNA polymerase can transcribe and translate the tryptophan structural gene
OPERIN IS "ON"
130
When there is tryptophan in the environment, the repressor protein is...
Activated by the tryptophan in the environment and stops natural transcription of tryptophan because its plentiful in environment (turkey day)
OPERON IS "OFF"
131
Permanent change in an organisms DNA
Mutation (1 mut per 1 bil replic.)
132
Permanent change in an organisms DNA
Mutation (1 mut per 1 bil replic.)
133
Ex of mutagens:
Exposure to UV
Xrays
Gamma rays
Benzopyrene
134
Mutations can be
Beneficial
Harmful
Neutral (3rd wobble)
135
Repair mechanism for mutation:
DNA polymerase proofreads and repairs as it copies DNA
136
Cancer causing agent
Carcinogen
137
3 Mechanics of Genetic Recombination
Transformation (recip. takes donor dna)
Transduction (bacteriophage)
Conjugation (pili sex)
138
Griffiths Experiment
Took 2 strains of Streptococcus pneumonia:
"S strain": smooth, capsule caused pneumonia
"R strain": rough, no capsule, no pathogenic
139
Conclusion of Griffiths experiment
Genetic recombination
Injecting heat treated "S strain" alone didnt cause pneumonia
Injecting both heat treat "S Strain" and regular "R Strain": R strain transformed into S strain by picking up lysed S DNA
140
Who identified transforming factor as DNA
Avery McCloud and McCarty
141
Transfer and integration of DNA from lysed donor bacterium to recipient bacterium
Discovered by Frederick Griffith
Transformation
142
Limitations of transformation
Only competent bacteria can take up DNA (less than 1% is naturally competent )
143
Transfer and integration of donor bacterium via using bacteriophage
Transduction
144
Limitations to transduction
Bacterioaphage has to effect donor + recipient bacteria
Same genus + species
Virus + host cell specificity
145
In prokaryotes DNA replication occurs ________ from a single point (the origin of replication or ori site).
Bi-directionally
146
Bacteria are used to produce human proteins including insulin, clotting factors, interferon, and growth hormone
True
147
The restriction enzyme BAMHI cuts all human DNA into the same number of fragments
False
148
Polymerase Chain Reactino is used to multiply RNA
False (used to multiply DNA)
149
Bacteria is the most common vector used in gene therapy
False
150
In most gene therapy studies, a _______ gene is inserted into the genome to replace an ________ disease-causing gene
Normal
Abnormal
151
Used to determine if a chemical is a mutagen of Salmonella.
Has to do with His - and His + Salmonella
The Ames Test
152
Transfer and integration of donor bacterium DNA into recipient bacterium by cell-to-cell contact (sex) (pili)
Conjugation
153
Who discovered Transformation?
Frederick Griffith, lab studied pneumonia (R) + (S)
154
Who identified transforming factor as DNA
Avery McCloud + McCarty
155
Virus that infect bacteria
Bacteriophage
156
Steps in transduction:
1. Phage attaches to RECEPTOR
2. Phage ENTER bacteria. Donor DNA is DEGRADED
3. Phage DNA uses donor cell machinery to produce PHAGE COMPONENTS
4. ASSEMBLY of PROGENY PHAGE
5. Donor bacterium is LYSED, and progeny phages are RELEASED + donate DONOR bacterium to the RECIPIENT. (TRANSDUCTION OCCURS)
157
Steps in F+ and F- Conjugation
1. F+ (D) attaches to F- (R) bacterium via PILI
2. ONE strand of F+ PLASMID DNA is transferred to the F- using the PILUS
3. Recipient bacterium makes ONE COMPLIMENTARY F PLASMID strand to match it and now both are F+
158
Steps in HFR x F- Conjugation
1. F+ cell's plasmid INTEGRATES into chromosome by recombination and turns to HFR
2. HFR and F- Cells join via pilus
3. PORTION (1/2) of F plasmid trailing WITH CHROMOSOMAL DNA goes into recipient
4. Donor chromosome+plasmid DNA is integrated into the F- chromosome but recipient bacterium is STILL F-
159
Are ubiquitoius and not cells
Viruses
160
Why are viruses not cells?
They do not fulfil the characteristics of life
161
How small are viruses?
Need EM to see them at 250,000x
162
What does it mean when we say viruses are OBLIGATE INTRACELLULAR
It means that the viruses must go inside a host cell to produce progeny like parasites
163
What are the viral components?
1. NUCLEIC ACID (viral genome)
2. CAPSID (protein coat)
3. Sometimes have VIRAL ENVELOPE (animals virsues)
164
What viruses have a viral envelope (sometimes)?
Animal viruses
165
How do viruses acquire envelopes?
From host cell during viral replication
166
What does HELICAL shaped viruses look like?
Spiral - capsid determines shape (rabies, ebola)
167
What does ICOSAHEDRAL look like?
aka Polyhedral = Spherical (herpes, polio)
168
What do COMPLEX viruses look like?
NOT helical or icosahedral (bacteriophage, smallpox, influenza)
169
What are 2 ways of viral replication?
Lytic (T4 bacteriophage+ E. Coli B)
Lysogenic (Lambda + E. Coli X)
170
Steps in LYTIC Replication:
1. ATTACHMENT: receptor specificity
2. ENTRY: BYOE (lysozyme) on cell envelope, injects nucleic acid (2 strands of DNA)
3. SYNTHESIS: lysozyme breaks done host DNA. uses host cell machinery
4. ASSEMBLY: nucleic acid inserted in capsid to build viral progeny
5. RELEASE: lysozyme comes back and lyses the cell
171
3 Entryways for ANIMAL Viral Replication
1. Direct Penetration (some non-enveloped)
2. Membrane Fusion (some enveloped)
3. Endocytosis (most enveloped + some non-enveloped)
172
Steps in ANIMAL Viral Replication:
1. Attachment: same; spikes increase attachement
2. Entry: 1 of the 3 ways
3. Synthesis: same; some are Retro Viruses (uses Reverse Transcriptase to turn into DNA)
4. Assembly: same
5. Release: Non-enveloped: progeny extruded via exocytosis > causes lysis in host
Enveloped: progeny extruded via exocytosis but take host cell membrane as their envelope > causes lysis
173
What do anti-viral drugs target?
ESAR
-Block ENTRY
-Block SYNTHESIS
-Prevent ASSEMBLY
-Prevent RELEASE
174
How do viruses + cancer contribute to each other?
Viral infection contributes to about 15-20% of all human cancers
175
Animal Viruses that can go latent:
HPV
Varicella-Zoster Virus (chx pox_
Herpes
176
Reactivation (inducing) factors in latent viruses
-Stress
-Increase in age
-Another infection
-UV light
177
Multiple Hit Hypothesis
-Takes multiple hits to cause cancer
-Virus = 1 hit
-Genetics, lifestyle...
178
How do some viruses contribute to cancer?
Virus inserts its DNA into human DNA, it then alters genes/proteins related to cell division
179
Gene that when activated transforms a normal cell into a cancer cell
Oncogenes
180
Proteinaceous infectious particle
Prion
181
What do prions do?
A protein that goes into your brain and unfolds proteins + refolds incorrectly
>Has a long incubation period
>Effects memory, coordination, balance
182
Prion brain disease:
Sponges = SPONGIFORM ENCEPHALOPATHY
183
Animal Prion Diseases
-Mad cow
-Chronic wasting disease (deer)
- Scrapie (sheep)
184
Human Prion Diseases
-CJ disease
-Kuru (ingesting dead brain)
-Fatal familial insomnia
