Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
67 Cards in this Set
- Front
- Back
|
Micrograph
|
Photographs taken through a microscope
|
|
|
Prokaryotes
|
Bacteria with no nuclear membrane or organelles, produce a specific type of cell wall
Micrometers |
|
|
Eukaryotes
|
Fungi and Protozoa
Cells that have a nucleus and membrane bound organelles, carrying types of cell wall or no cell wall mm |
|
|
Viruses
|
nm
Must enter living cells in order to survive Specific to all forms of life |
|
|
Fungus
|
Largest
Nucleus, cell wall (polysaccharides) |
|
|
Colony
|
Group of organisms, genetically identical, derived from a single or small clump of organisms
Bacteria- smooth, opaque, transparent, or translucent Fungi-fuzzy |
|
|
Minimal media
|
Contains fewer nutrients than TS and is more difficult for organisms to grow on
Organisms that can produce the most molecules needed for growth will grow best |
|
|
TSA
|
Contains all nutrients
|
|
|
Cytoplasmic Membrane
|
Layer immediately inside the cell wall
|
|
|
Cell Wall
|
Strong rigid layer giving bacteria its shape
|
|
|
Morphology
|
Shape
|
|
|
Peptidoglycan
|
What majority of prokaryotes make cell wall out of
Layers of NAG and NAM sugar chained together in long polymers held together by short peptides Thick- 2 layers Thin- 3 layers Humans cells do not have |
|
|
Cell Envelope
|
General term for combination of wall and membrane layers every bacterium has
|
|
|
Hans Christian Gram
|
Created stain to cause bacterially infected tissues to stand out in obvious contrast to infected cells tissue
Distinguish thick and thin walled bacteria Results show positive or negative cell wall and morphology |
|
|
Gram Positive
|
Dark purple
Stain gets stuck in thick cell wall |
|
|
Gram Negative
|
Light Pink
Stain washes out of think wall |
|
|
Cell Membrane
|
selectively permeable lipid bilayer of proteins and lipids
|
|
|
Anaerobic Infections
|
Anaerobes in normal flora
|
|
|
Facultative Anaerobes
|
Organisms that can switch between aerobic and anaerobic
Can grow with out O2, but will use O2 if present Luxuriant growth at surface, notable growth throughout agar Need O2 sometimes Gas production Glycolysis, Krebs Cycle, ETC, Fermentation |
|
|
Strick Anaerobes
|
Oxygen intolerant bacteria that make all energy via anaerobic processes
Low oxygen tension causes great tissue damage Growth throughout depths of tube, no growth at surface Oxygen toxic Gas production Glycolysis, Fermentation |
|
|
Strict Aerobe
|
Growth at surface only
Requires O2 Glycolysis, Krebs Cycle, ETC |
|
|
Aerotolerant Anaerobe
|
Some growth at surface with more growth in O2 free regions
Can turn O2 into nontoxic usable Does not use O2 for growth, but tolerates it Glycolysis, Fermentation |
|
|
Sterile Dilution
|
Dilute bacterial suspension in order to count viable bacteria, dilute chemicals or proteins in order to assay their potency over a range of concentrations
Dilute sample in several small steps and plate a small volume from each dilution |
|
|
Virion
|
Viral Particle
Enter host and multiply |
|
|
Capsid
|
interlocking proteins to surround and protect viral genes
Some have membrane envelope Some have quiet viral enzymes, used for quick replication |
|
|
(+) SS RNA
|
Behave like mRNA molecules-->go directly to ribosome
|
|
|
(-) SS RNA
|
Do not act like mRNA
Genomes must be copied into positive strand by RDRP Have RDRP --> ribosome translation |
|
|
Acute Infections
|
Rapid viral replication
Kill host cell Host defenses altered quickly Short lived |
|
|
Persistent Infections
|
Slowly replicate and release
Months to years Latent-live |
|
|
Transcription
|
Rewriting the same gene language
DNA-->RNA Nucleotide--> Nucleotide |
|
|
Translation
|
Rewriting (translating) to a different language
RNA--> Protein Nucleotide--> amino acid |
|
|
Direct Selection
|
Selecting for a specific phenotype
Find one individual mutation amongst millions of other cells |
|
|
Cytoplasmic Enzymes
|
Workers and builders of cell
Construct all other parts that life requires |
|
|
Ribosomes
|
Move along mRNA
Overtakes tRNA with amino acids, empty tRNAs then exit Takes amino acids from tRNA --> join them together to make a new protein |
|
|
RNA Polymerase
|
Protein on DNA
Transcribes RNA strand from DNA strand Synthesize RNA 5'to3' by traveling on template in 3' to 5' direction |
|
|
Central Dogma
|
DNA acts as template for enzymes to read
RNA polymerase=transcription Ribosome=translation |
|
|
DNA/RNA Polymerase
|
Make new strands of nucleic acid from DNA template
Base pairing with complementary on DNA template 5' phosphate of incoming with 3' OH of growing |
|
|
Coupling
|
Why bacteria grow and respond quickly between transcription and translation
Recycle mRNA quickly after transcription |
|
|
Promoter Sequence
|
Always ahead of a gene or operon
Fits into binding pocket in RNA polymerase |
|
|
Terminator Sequence
|
End of transcription
RNA polymerase leaves DNA and drops RNA |
|
|
Start Codon
|
Where ribosome begins synthesis of proteins
AUG |
|
|
Stop Codon
|
End of ribosome translating
UGA UAG UAA |
|
|
Triclosan
|
Active ingredient in antibacterial hand soap
Acts like antibiotic-specifically inhibits one enzyme-->Enoyl Reductase |
|
|
Silent Mutation
|
Least serious
Mutated DNA causes a different codon to be transcribed in the mRNA, but altered codon results in wild type amino acid |
|
|
Missense Mutation
|
Change in protein structure
Mutation leads to a different amino acid--> protein works less efficiently Mutated protein mistakes one amino acid for another Little or serious effect-depends on amino acid to function |
|
|
Beneficial Missense Mutation
|
Antibiotic resistance
Mutant grows |
|
|
Antibiotics
|
Kill or Inhibit bacterial growth by binding specifically to one key enzyme on a specific spot on enzyme
Interferes with enzymes ability to catalyze a reaction Enzyme can't do job--> bacteria unable to manufacture and grow Can control organisms once they have breached to barriers of the human body |
|
|
Rapid Susceptibility Testing
|
Guarantee agent chosen is effective and preserve last line of defense drugs for very persistent organisms
|
|
|
Agar Based
|
Diffusion of antimicrobial chemicals from regions of high concentration to low concentration on petri plate
Larger zone of inhibition=greater sensitivity to antibiotic KB and E Test |
|
|
Kirby Bauer Test
|
Concentration added to disk on agar surface
Zone size susceptible intermediate or resistant Miller H Agar, incubate with antibiotic and bacteria Measure inhibition zone: predict effectiveness of antibiotic, larger= more susceptible No MIC |
|
|
Susceptible
|
Antimicrobial agent can be appropriate for treating the infection caused by isolate tested resistance absent or insignificant
|
|
|
Intermediate
|
May be of use, may inhibit, prevent major swings from resistant to sensitive
|
|
|
Resistent
|
Antimicrobial agent not appropriate choice for treating infection caused by isolate tested
Organism might not be limited |
|
|
Broth Dilution
|
Bacteria inoculated into tubes containing nutrients and serial dilution of the antibiotic
Inhibitory levels=no turbidity Test tubes with growth of turbidity MIC- choose little to no turbidity |
|
|
Minimum Inhibitory Concentration (MIC)
|
Numerical value of concentration in tube showing no visible growth, tube with lowest antibiotic concentration that prevents visible turbidity after 18-24 hours
Smallest concentration of a drug that is required to inhibit the growth of a microbe |
|
|
E-Test
|
Agar medium with antibiotic strip linear gradient
Bacteria fail to grow where concentration is too high MIC read directly from plate where growth intersects |
|
|
Phenotypic Assay
|
Assay isolate for presence of specific enzyme that is known to cause resistance, expression of functional enzyme in bacteria is detected
Changes color to detect bacteria Hydrolyzed=pink --> B lactamases--> resistant to penicillin Unhydrolyzed=yellow |
|
|
B-Lactamase Activity
|
Penicillin resistent
Cleave ring making antibiotic no longer fit and inhibit peptidoglycan building enzymes that are the target |
|
|
Joseph Lister
|
Phenol (carbolic acid) to control surgical infections
Phenol=Disinfectant |
|
|
Disinfectant
|
Chemicals used to control growth of microbes on living tissues and inanimate objects
Act nonspecifically on large group of components No single disinfectant appropriate for all circumstances Clear microorganisms from environment before they can enter the body |
|
|
Disk Diffusion Method
|
Evaluate effectiveness
Disk of paper soaked with chemical placed on agar previously inoculated with organism Zone of inhibition- no growth--> determines effectiveness Larger zone= more sensitive/susceptible the bacteria to the used disinfectant |
|
|
Frameshift Mutation
|
Most Serious
Deletion or insertion of an amino acid causes encoding for a nonsense protein (stop codon) |
|
|
Triclosan-Resistant Mutants
|
Mutations in DNA allows growth in presence of Triclosan
|
|
|
Viral Damage
|
Host Cell directly killed by viral infection
Host immune defenses kill virus containing cell |
|
|
RNA Dependent RNA Polymerase (RDRP)
|
In viral replication:
Turns (-) RNA into (+) strand RNA, and visa versa Produces copies of viral genome to complete cycle translation |
|
|
Choosing a Disinfectant
|
Microorganism being treated (what you want to inhibit)
Material being treated (surface) Degree of contamination Exposure time Strength and action |
|
|
Virulence Factors
|
Give the pathogen an advantage at the site of infection
|
