Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Micro > Week 8 Exam 3 > Flashcards

Week 8 Exam 3 Flashcards

1
Q

Classification

A 
Linnaeus
- order & organization
- predictions on structure & function
- understand evolutionary connections
organisms are grouped into taxa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Taxonomy:
Namenclature:
Classification:
Identification:

A

Taxonomy: science of classifying things (reflects phylogeny)
Namenclature: assigns scientific names to taxonomic categories & individuals
Classification: orderly arrangement of organisms into a hierarch(trees)
Identification: process of discovering & recording traits for taxonomic placement

  • bacterial strain: population of cells that arose from a single cell
  • species share at least 70% common DNA sequences
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Carl Woese

A
  • created 3 domain system : bacteria, eukaryote, and archaea
  • created by: comparing rRNA sequences
  • rRNA: ribosomal RNA, in all organisms, crucial for protein synthesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Microbial Methods for Identification

A
  • phenotypic: physical characteristics, biochemical tests, phage typing
  • serological tests: immunologic(antibody/antigen binding)
  • genotypic: analysis of nucleic acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Phenotypic Methods

A

observation of traits/appearence/behavior

  • types of enzymatic activities it can carry out
  • physical conditions it thrives in
  • antibiotics its susceptible to
  • chemical composition of cell wall
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Immunologic methods

A
  • antibody response: patients sample is tested for presence of antibodies to a suspected pathogen (easier than testing for the microbe) ex. covid PCR, mono, group a strep
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Genotypic Methods advantages

A

advantages: culturing is not necessary, rapid results, more precise than phenotypic methods, can be used for microbes not easily grown in the lab, can tell you the strain/species

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

Proper specimen collection:

A
  • aseptic technique
  • sterile sample containers & tools
    only infected site should be sampled
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Sputum collection techniques

A
  • coughing into container
  • catheter
    (contamination with saliva should be avoided due to millions of bacteria per milliliter)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Urine collection samples

A
  • aseptically: catheter
  • clean catch: washing external urethra and collecting urine midstream (any contamination will be differentiated)
  • mucus lining of urethra, vagina, or cervix with swab or applicator stick
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

sterile body fluids collection samples

A
  • blood, cerebrospinal fluid and tissue fluid by sterile needle aspiration
    antisepsis of puncture site in extremely important
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

other specimen sources:

A
  • eye, ear canal, synovial fluid, nasal cavity: swab

- diseased tissue: surgically removed (biopsied)

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

Phenotypic methods: Immediate examination

A

-direct microscope observation of fresh or stained specimen
most rapid
stains often used: acid fast & gram

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

Phenotypic methods: 24 hour examination

A

growth of specimen on a media

  • specialized media: grow pathogen over the amount of microbiota (increase in numbers of pathogen)
  • selective media: used for non sterile specimens that contain a large amount of normal microbiota
  • differential media: looks for distinctive characteristics and fermentation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Phenotypic methods: physical characteristics

A

after growth

  • identified based on cellular morphology
  • differential staining or structural staining
  • distinct colony morphology of appearance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Phenotypic methods: biochemical tests

A 
useful if microbes can grow under lab conditions
provides evidence of enzymatic systems
-fermentation of carbs
-utilize specific substrates
-produce waste products
-fatty acid composition
17
Q

Automated microscan system

A
  • tool for rapid identification based on metabolic characteristics PHENOTYPIC
  • multi-welled plate (98), use variety of chemical tests
  • color change=presence of a particular metabolic reaction
18
Q

dichotomous key

A

physical characteristics are based on D. key

-branching decision tree to help identify a microorganism

19
Q

antimicrobial sesceptibility testing

A

useful in deterring which drugs will be used in treatment because of the rise of antimicrobial resistance
-phenotypic test

20
Q

phage typing

A

helps identify bacterial strains
- phages: specific to host they infect and can be used to identify bacterial strains
- USE: bacteriophage (viruses that infect bacteria) to detect strain of bacteria
swab plate w/ bacteria you are wanting to identify, pipet small values of bacteriophage, a plaque(where the bacteriophage has infected the bacterium)
- bacteriophage infection observed using plaque assay
-phenotypic test

21
Q

Drawbacks of Phenotypic methods:

A
  • the microbe needs to be cultured: takes minimum of 18-24 hours
  • many can be noonculturable, leaving the possibility that e culture normal microbiota
22
Q

specificity

sensitivity

A
  • specificity: focus on certain antigen and not react with unrelated antigen
  • sensitivity: detection of small amount of antibodies
    most effective immune testing has these
23
Q

immunological methods: serology

A
  • in vitro testing of serum, urine, cerebrospinal fluid, whole testing and saliva for presence of specific antibodies
  • antibodies have an extreme specificity of antigens
  • viewing interaction of antigens and antibodies microscopically or macroscopically provides a powerful tool for detecting, identifying, and quantifying them
  • determines: immunologic status of patient, confirm a suspected diagnosis, and screen individuals for a disease
24
Q

immunological tests: agglutination and perception reactions

A
  • antigen is interlinked by many antibodies to form insoluble aggregates that settle in solution
  • forms clumps
25
Q

immunological tests: immunochromoatography

A
  • lateral flow test (pregnancy and rapid strep tests)
  • plastic cartridge contains porous material or polymer that directs fluid
  • patient sample will encounter antibodies
  • if patient sample contains correct antigen, it will bind the antibodies
  • then a third molecule is impregnated on the paper in a strip form
26
Q

immunological tests: immunofluorescence

A
  • florescent antibodies (FAbs): monoclonal antibodies labeled by florescent dye
    direct testing:
  • unknown antigen is fixed to a slide and exposed to a FAb solution
  • if antigen-antibody complexes form, they will stay bonded to the sample and can be seen under a florescence microscope
  • valuable for: locating microbial antigens on cell surfaces or tissues

indirect testing:

  • FAbs recognize the Fc reign of antibodies in patient sera
  • known antigen is added to the test serum
  • binding of fluorescent antibody is seen through florescence microscope
  • fluorescing aggregates or cells indicate the FAbs have complexed with microp-specific antibodies
27
Q

Enzyme-linked immunosorbent assay (ELISA)

A
  • uses an enzyme-linked indicator antibody to visualize Ag-Ab reactions
  • relies on microtiter plate that will absorb the reactions

indirect:

  • detects microbe specific antibodies in patient area
  • known antigen is absorbed to the surface or a well and mixed with unknown antibody
  • if ag-ab complex forms, in added indicator antibody will bind and produce a color change

direct:
- known antibody is absorbed to the bottom of the well and incubated with an unknown antigen
- if ag-ab complex forms, it will attract the indicator antibody and produce a color change

28
Q

antibody titers

A
  • concentration of antibodies in a sample
  • determined by: serial dilution of patient serum
  • the more the sample can be diluted, the greater the concentration of antibodies and its titer
  • used to: diagnose autoimmune disorders and determine past exposure to diseases
29
Q

sterotyping

A
  • ag-ab technique for identifying, classifying, and subgrouping bacteria into categories
  • employs antisera (antibodies) against cell antigens like capsule, flagellum and cell wall
  • used for: identifying salmonella species and strain
  • basis for differentiating pneumococcal and streptococcal sterotypes
30
Q

genotypic methods: polymerase chain reaction PCR

A
  • production of numerous identical copies of DNA or RNA molecules
  • can amplify little amounts of nucleic acids present in a sample

-real-time PCR (qPCR) q=quantitative
uses fluorescent labeling during amplification
level of fluorescence is measured in real time as it is running
fully automated and faster, analysis of DNA not needed

-reverse-transcriptase PCR (RT-PCR)
creation of DNA out of RNA
used for identification of RNA viruses

31
Q

genotypic methods: whole genome sequencing

A
  • useful for rapid analysis of outbreaks and drug-resistant organisms
  • will become so cheap and routine we will test from the patient to find microbes causing symptoms
32
Q

genotypic methods: pulse-field gel electrophoresis: microbial fingerprints

A
  • separation of DNA fragments
  • slowly applying alternating voltage levels to the gel from 3 different directions
  • allows similarly sized DNA fragments to separate
  • used in: food borne outbreaks
33
Q

genotypic methods: microbial fingerprints: pulsenet

A
  • program established by CDC to assist in the investigation of disease food borne outbreaks
  • sciencists from across the country can help and it will take hours
34
Q

genotypic methods: nucleic acid composition

A
  • prokaryotic G + C content varies 20%-80% between different species
  • closer the percentage between the two bacteria, the more closely related they are

Micro (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions