Physical & Chemical Control
Chemotherapeutics
Miscellaneous 1
Transcription & Translation
Miscellaneous 2
100
What are some limitations to using an autoclave?
Melting of some plastics Sharp objects can become dull Oily substances are not effectively sterilized
100
What is a toxic dose and therapeutic dose?
Toxic dose- the maximum limit of the chemotherapeutic that can be tolerated by a human Therapeutic does-the minimum amount of chemotherapeutic needed to eliminate the pathogen from the host
100
What are the three movements of DNA among bacteria?
Recombination, Vertical gene transfer, Horizontal gene transfer
100
What is the enzyme used in bacterial transcription?
RNA polymerase
100
What is the difference between sterilization and sanitization ?
Sterilization- the destruction or removal of all living microbes Sanitization – the reduction or inhibition of microbial contamination
200
What are the temperatures and times for the three different types of pasteurization?
Pasteurization- 63 degrees Celsius for 30 min Flash Pasteurization- 71.6 for 15 min Ultra high pasteurization-140 for 3 sec
200
Why are sulfonamides used as a chemotherapeutic?
Interferes with folic acid synthesis which is necessary for nucleic acid synthesis Competitive inhibition - competes for enzyme active site
200
What information is carried on plasmids?
R factors, Bacteriocins, F factors,Virulence factors
200
What enhances promoter recognition in bacterial transcription?
sigma factor
200
In the presence of lactose or allolactose , does RNA polymerase bind to the the lac operon? why or why not?
Yes, because the inducer binds to the repressor so the repressor is not longer bound to the operon. Therefore, RNA polymerase can transcibe the genes for lactose breakdown
300
Give an example of a chemical that is used to achieve sterilization and explain how it works?
Answers may vary. Aldehydes- inactivate proteins and nucleic acid by cross-linking
300
What antimicrobials are used to inhibit mycolic acid synthesis?
Ethambutol and Isoniazid
300
How can you minimize antibiotic resistance with antibiotics?
1. Treatment can include an inhibitor to an enzyme that may degrade antibiotic e.g. augmentin Amoxicillin plus beta-lactamase inhibitor 2. Treatment can include 2 antibiotics; second only gets activated if first antibiotic is disabled e.g. beta-lactam + quinolone combination
300
How are prokaryotic and eukaryotic mRNAs processed differently?
Answers may vary. prokaryotic-RNA transcribed and translated in cytoplasm Some mRNAs can hold information for more than one protein Polycistronic mRNA eukaryotic-Most eukaryotic genes do not have continuous protein-coding regions Exons and Introns
300
What is the difference between infection and disease?
Infection is the multiplication of a microbe within a host, competing for resources and space Disease results if the invading microbe affects normal body functions Lowers overall state of health
400
What chemicals can be used to denature the proteins of bacteria?
Phenol and phenolic compounds and ethanol.
400
How do Chloramphenicols inhibit protein synthesis?
Block peptide bond formation by the ribosome (50S) Work on a variety of gram positive and gram negative bacteria
400
What is the process of transduction?
Viruses are the mode of transmission Bacterial viruses (phages) infect susceptible bacteria Degrade host DNA Occurs as a result of errors in virus life cycle during repackaging Can transfer bacterial genes if phages do not lyse (kill) infected bacteria Usually species specific, due to infection specificity of viruses
400
What are the three types of RNA that result from transcription and used in translation?
mRNA,rRNA, tRNA
400
What are the stages of an infectious disease?
incubation period, prodomal,acute period, period of decline, period of convalescence.
500
Why is using hydrogen peroxide on open wounds not recommended ?
Catalase in our tissues convert hydrogen peroxide to water and oxygen gas
500
If i wanted to prevent tRNA attachment to the small subunit of bacteria, what chemotherapeutic would I used?
Tetracylines
500
What are the four mechanisms of antibiotic resistance?
1. Altered metabolic pathway Bacterial enzymes mutate to be unaffected by antibiotic or use an alternate metabolic pathway 2. Antibiotic inactivation Penicillinase cleaves -lactam groups 3. Reduced permeability or active export Proteins can be used to pump antibiotic out of cell 4. Target modification Bacterial targets mutate so antibiotic no longer binds to its target (If ribosomes were slightly different—streptomycin ineffective!)
500
What does the start codon(AUG) code for in bacteria
formyl methionine (f-met)
500
Explain why a fecal transplant could be effective treatment for C.diff infections
Answers may vary.
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