MICROBIO EXAM #2
Which type of agent will kill bacteria?
Bactericidal
The enzyme responsible for building the new strands of DNA in PCR is called
Blank 1: DNA or Taq Blank 2: polymerase
A situation where microbes begin to tolerate an antimicrobial agent at a level which would normally be inhibitory is called ___ ___
Blank 1: drug, antibiotic, or antimicrobial Blank 2: resistance
Antimicrobial solutions with alcohol or water-alcohol mixtures as the solvent are called
Tinctures
An organic substance that contains a -CHO functional group on a terminal carbon is a(n)
aldehyde
RNA molecules differ from DNA molecules because only RNA ________. has ribose has uracil is typically one strand of nucleotides does not have thymine
all
Among the microorganisms, various genomes can include ______.
all chromosomes plasmids mitochondrial DNA chloroplast DNA
The benefit of the bacterial operon is that ________.
since the proteins coded for by the operon structural genes work as a team, they are regulated (i.e. induced or repressed) as a team, thus saving energy
Bacterial cells described as persisters are resistant to antibiotics because they ______.
slow or stop their metabolism in the presence of the drug
Which of the following are some of the desirable qualities in a germicide?
solubility in a solvent broad-spectrum action not corrosive and nonstaining rapid action
Changes to the genome of an individual that are not passed on to offspring are termed _____ therapy.
somatic cell
Gene therapy leading to changes that are permanent in the individual who is treated, but not passed on to the offspring, is called __ __ gene therapy
somatic cell
Match the term to its description to test your understanding of the use of moist heat to control microbial growth.
steam under pressure- Requires use of an autoclave. To sterilize, temperature must reach 121°C for a minimum of 15 minutes. boiling water-100°C, 30 minutes will disinfect but will not sterilize. pasteurization- Heat applied to beverages to prevent spoilage and kill pathogens. Protocols include holding liquids at 71.6°C for 15 seconds or at 63°C for 30 minutes. Does not sterilize.
Match the term to its description to test your understanding of the use of moist heat to control microbial growth.
steam under pressure- Requires use of an autoclave. To sterilize, temperature must reach 121°C for a minimum of 15 minutes. boiling water-100°C, 30 minutes will disinfect but will not sterilize. pasteurization-Heat applied to beverages to prevent spoilage and kill pathogens. Protocols include holding liquids at 71.6°C for 15 seconds or at 63°C for 30 minutes. Does not sterilize.
A process that completely removes or destroys all viable microorganisms, including viruses, from an object or habitat is referred to as
sterilization
Destroying or removing all viable microorganisms, including bacterial endospores as well as viruses, is called ______.
sterilization
Zones that indicate susceptibility to tetracycline are greater than 19 mm, whereas resistance is indicated with a zone less than 14 mm. Looking at this image of a Kirby-Bauer test, if the top antibiotic disc represented the zone seen around a tetracycline disc, this organism would be considered ________ to tetracycline.
susceptible
What is the role of reverse transcriptase?
synthesizes DNA from RNA
During replication, each parent DNA strand serves as a _______ for synthesis of new DNA strands.
temmplate
CRISPR has been used to treat antibiotic-resistant infections by directing specific gene cuts to _____.
the antibiotic resistance genes
The basic premise of gene therapy is that ________.
the error in protein production from a defective gene is overcome by the insertion of the correct gene from a healthy cell into the patient's tissue
Sanitization is a process by which _______.
the microbial load on an object is reduced
The ratio of the dose of a drug that is toxic to humans compared to its minimum effective dose is called the ______.
therapeutic index
Dissolving a solid or gaseous antimicrobial chemical in pure alcohol or an alcohol-water mixture produces a(n) ______.
tincture
The RNA molecules that carry amino acids to the ribosomes during protein synthesis are called _______.
transfer rna
The jumping of a gene from one location to another is done by _______.
transposons
True or false: Drugs that are effective against fungi have a strong possibility of being toxic to humans because both organisms are eukaryotes.
true
True or false: The nature and sensitivity of the microorganism and the overall medical condition of the patient need to be considered before antimicrobial treatment begins.
true
True or false: The use of recombinant DNA for gene cloning is shown in this image.
true
true false: A recombinant organism is one that has sustained a change in its genome through receipt of DNA from a different organism.
true
true false: Transcription occurs in the nucleus or at the nucleoid.
true ??
One consequence of widespread use of ______-spectrum antibiotics is the development of resistance in ______ microbes that are part of the normal biota.
broad; bystander
Vegetative cells directly exposed to normal room air gradually become dehydrated or ______.
dessicated
true false: Induced mutations result from errors in DNA replication.
false
true false: The smallest unit of heredity is a chromosome.
false
true false: DNA replication proceeds in one direction around the bacterial chromosome.
false ??
Ivermectin and praziquantel are newer drugs used for the treatment of _____.
helminth infections
Cytoplasmic enzymes are most likely to be disrupted by ______.
high temperatures
An antimicrobial drug with a _______ therapeutic index is a better choice than one with a _______ therapeutic index.
high, low
Aldehydes are organic substances that contain a _____ functional group on a terminal carbon.
-CHO
1. The patient has a central venous line for administration of IV fluids and medications. Which of the following interventions demonstrates aseptic technique by the RN when manipulating the line? 2. Which of the following agents is/are most appropriate for use for skin antisepsis when performing a routine dressing change of the central venous line? 3. Which of the following is the most important point of teaching for visitors to prevent the patient from being exposed to other infectious agents? 4. What is the goal of the use of a high-efficiency particulate air (HEPA) filter in the patient's room?
1. .All of these choices are correct. 2. Alcohol and chlorhexidine 3.Hand hygiene by washing or antiseptic hand sanitizer application when entering and leaving room 4. Air decontamination Correct
Effects of Triclosan on the Microbiome 1. What percentage of the general population carries Staphylococcus aureus in their nasal cavity or throat? 2. Which infection is not commonly linked to Staphylococcus aureus? 3. Studies have found triclosan in _______. 4. Of the four main categories, what two cellular targets are used by triclosan to kill microbes? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.) 5. What was the main research question in this particular study? 6. Which statement best summarizes the data in figure 1 graph B? 7. According to assays conducted by these researchers, triclosan increased the capacity of S. aureus to _______. 8. The researchers observed a similar relationship between triclosan and S. aureus colonization in an animal model.
1. 30% 2. Encephalitis 3. Triclosan has been found in all of these choices. 4. protiens, cell membrane 5. Does the presence of triclosan in human nasal secretions increase the likelihood of S. aureus colonization? 6. Subjects with higher levels of triclosan in their nasal secretions were more likely to be colonized with S. aureus 7. attach to host proteins and surfaces 8. true
An Unexpected Effect Read the case file and complete the activities that follow. Janet, a 25-year-old secretary, was admitted to my floor of the hospital with symptoms of kidney infection, including chills, fever, flank pain, nausea, and malaise 1. At which time point did you first detect hearing impairment via audiogram analysis? 2. What action did you take in this study to accurately determine if the patients were experiencing hearing impairment over time? 3. Which statement is correct regarding the data collected after drug treatment was complete?
1. 4 months 2. You took a baseline audiogram for each patient to establish the efficiency of their hearing before treatment. 3. The percentage of patients with hearing impairment after drug treatment ended remained constant, indicating this was likely permanent damage.
The therapeutic index of a drug is the ratio between the dose that is toxic in 50% of patients to the dose required to produce a therapeutic effect in 50% of patients. 1. Gentamicin has a low therapeutic index compared to vancomycin, which has a higher therapeutic index. Which drug has the lowest toxicity? 2. Drug A has a TD50 of 25 μg/ml and an ED50 of 21 μg/ml. Drug B has a TD50 of 28 μg/ml and an ED50 of 14 μg/ml. Which drug is the riskier choice? 3. High selective toxicity yields a _______.
1. Vancomycin 2. drug a 3. high TD50 value and therefore a high TI
Use of Chemicals in Healthcare 1. Alcohol acts as a surfactant and a protein coagulant. Which of the following statements are true concerning its mechanism of action? 2. Is it likely that the increase in antibiotic-resistant organisms is related to the increase in handwashing in healthcare facilities? 3. Until 2019, triclosan was a phenolic compound present in some hand sanitizers that targeted a specific protein mediating fatty acid synthesis. Were microbes more or less likely to develop resistance to triclosan than to alcohol?
1. 70% ethanol is a better microbicide than 100% alcohol since water molecules are necessary to coagulate proteins. 2. No, because the increase in antibiotic-resistant organisms is a result of exposure to antibiotics, not alcohol. 3. More likely, since triclosan has a specific target which can be altered genetically, whereas alcohol's surfactant properties cannot be avoided.
NCLEX: Clinical Application Read the clinical scenario, and then answer the questions that follow. A 30-year-old male has returned from a trip to South America, where he reports spending time in crowded living conditions. Upon assessment of a tuberculosis skin test, the patient is found to be reactive to the purified protein derivative (PPD) injected into the skin. 1. Which of the following medications are used to treat tuberculosis? 2. The RN advises the patient that drug therapy is being started prophylactically. Which of the following statements by the patient best demonstrates understanding of this principle? 3. The RN advises the patient that the drug therapy may be hepatotoxic. This will require routine monitoring of which of the following blood labs during the course of treatment? 4. When is the patient advised to stop taking his antibiotics?
1. All of these are used to treat TB 2. I am being treated to prevent the progression of latent to active tuberculosis infection 3. Liver function tests 4. When the full prescribed course is complete Correct
NCLEX: Clinical Application Read the clinical scenario, and then answer the questions that follow. A 67-year-old oncology patient is admitted to the intensive care unit with the diagnosis of sepsis. The patient has exhibited a persistent fever for 24 hours, followed by low blood pressure and high heart rate. His blood cultures are positive for growth of gram-positive cocci. The patient is initially stabilized with fluid administration and antibiotic therapy is initiated. 1. The patient has a central venous line for administration of IV fluids and medications. Which of the following interventions demonstrates aseptic technique by the RN when manipulating the line? 2. Which of the following agents is/are most appropriate for use for skin antisepsis when performing a routine dressing change of the central venous line? 3. Which of the following is the most important point of teaching for visitors to prevent the patient from being exposed to other infectious agents? 4. What is the goal of the use of a high-efficiency particulate air (HEPA) filter in the patient's room?
1. All of these choices are correct. 2. Alcohol and chlorhexidine 3.Hand hygiene by washing or antiseptic hand sanitizer application when entering and leaving room 4. air decontamination
An 8-year-old male patient presents to his primary care physician with symptoms of influenza. The patient has a history of respiratory compromise secondary to cystic fibrosis. The physician orders drug therapy to be initiated on this patient. 1. Which of the following chemotherapeutic agents would the RN anticipate to be ordered for this patient? 2. The physician prescribes the drug oseltamivir (Tamiflu) for this patient. Which of the following describes the action of Tamiflu? 3. The patient's mother asks how to prevent the virus from spreading to her other two young children at home. All of the following are important points of discharge education to be addressed by the RN, except:
1. Antiviral 2. All of these are actions of Tamiflu. Correct 3. The children at home should be started on antibiotics Correct
Control of Microorganisms in the Operating Room 1. Of the three major types of healthcare-associated infections, which type continued to see increased incidence as of 2011? 2. 2. Based on the information in this chart, if there were 20,000 SSIs in 2008, approximately how many SSIs occurred in 2013? 3. 3. Healthcare-associated infections caused by MRSA and C. diff saw a ______ incidence during 2011-2013. 4. According to this data, hospital practices had the greatest impact on the incidence of which of the three major types of healthcare-associated infections?
1. CAUTIs 2. 16,000 3. declining 4. CLABSIs
Hospital Cleaning Practices 1. What was the purpose of this article? 2. Personnel issues can contribute to suboptimal cleaning and disinfection in which of the following ways? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.) 3. What was depicted in Figure 1? 4. What germicidal category has demonstrated better effectiveness as liquid disinfectants? 5. What category of germicide has been used to create "self-disinfecting" surfaces? 6. True or false: Aerosolized hydrogen peroxide has proven to be sporicidal in all studies. 7. Which "no-touch" room decontamination method showed significant effectiveness against MRSA, Acinetobacter, and C. difficile?
1. Discuss issues and new approaches to cleaning and disinfection practices in hospital settings 2. *Many surfaces are not wiped down by housekeepers *Variability across housekeeper performance *turnover or shortages of personnel 3. A contaminated quat disinfectant actually increased the microbial load on a patient's table. 4.Hydrogen peroxide 5.heavy metals 6. false 7. Vaporized hydrogen peroxide systems
Skin rash 1. The physician anticipates Streptococcus pyogenes to be the causative organism and orders penicillin for this patient. What is the rationale for initiating this antibiotic treatment prior to final microbial identification and sensitivity results? 2. Which of the following statements is true of penicillin's mechanism of action and demonstrates the concept of selective toxicity? 3. Prior to ordering penicillin for this patient, which of the following components of the patient's medical history is most important to assess? 4. Which of the following is the most common allergic reaction to penicillin? 5. After discharge, the patient calls the urgent care clinic to report a feeling of tightness in his throat and difficulty breathing within 30 minutes of taking his first dose of penicillin. What should the RN advise the patient?
1. This particular pathogen is almost universally sensitive to penicillin. 2.Penicillin inhibits the synthesis of the cell wall in bacteria by blocking the chemical peptidoglycan. 3.Drug allergies 4.Skin rash 5.Call 911 for emergency medical attention
An Unexpected Effect Read the case file and complete the activities that follow. Janet, a 25-year-old secretary, was admitted to my floor of the hospital with symptoms of kidney infection, including chills, fever, flank pain, nausea, and malaise. 1. Which of the following results from patient testing indicated a bacterial infection? 2. Gentamicin is an antibiotic that inhibits ________. 3. Most urinary tract infections are caused by _______, such as Proteus mirabilis. ----------------------------------------- 1. True or False: Antibiotics inhibiting peptidoglycan synthesis will negatively affect both bacterial and host cells. 2. Which drug blocks the action of pyrophosphatase, thus inhibiting the transport of important molecules for cell wall synthesis across the bacterial membrane? 3. Which drug exerts its effect by weakening the cell wall until the bacterial cell is lysed? 4. Which antibiotic inhibits the action of transpeptidase, resulting in weakening of the cell wall structure of bacteria? ---------------------------------------- 1. The patient is next treated with streptomycin. Is there a possibility she could still experience ringing in her ears? 2. Which of the following antibiotics are not involved in the blocking of cell wall synthesis and repair? 3. Many of the antibiotics discussed in the animation target _______, such as pyrophosphatase and transpeptidase, involved in cell wall synthesis.
1. Elevated white blood cell count 2. protein synthesis 3. gram-negative bacilli ---------------------------- 1. false 2. Bacitracin 3. Vancomycin 4. Penicillin --------------------------- 1. Yes, streptomycin is another aminoglycoside antibiotic. 2. Trimethoprim 3. enzymes
Preparing the Skin 1. Betadine belongs to what group of chemical control agents? 2. Which of the following is NOT a major cellular target of chemical antiseptics and disinfectants? 3. True or false: Sterile saline has sterilizing effects on the skin.
1. Halogens 2. Cytoskeleton 3. False
1. What is the most important action by the RN prior to beginning the dressing change? 2. The RN applies a silver-impregnated dressing to the ulcer. What is the rationale for the use of silver dressings in wound care for this patient? 3. The wound care RN uses hydrogen peroxide in wound cleansing. Which of the following terms best represents the treatment goal with the application of this chemical agent? 4. Which of the following would not be killed by standard-concentration hydrogen peroxide?
1. Hand hygiene 2.Silver possesses antimicrobial activity 3.Antisepsis 4.Endospores
1. What is the most appropriate method of sterilization for metallic surgical instruments? 2. During a surgical procedure, the RN observes a surgeon wearing sterile gloves brush his posterior hand surface on a tray. The tray had been cleaned with a liquid chemical agent. What is the most appropriate action by the RN? 3. Which of the following microbes may still be present on sterile surgical instruments? 4. What is the RN's most appropriate action with used needles following the completion of the procedure?
1. Pressurized steam 2. Assertion to the surgeon that a change of gloves is necessary before continuing the procedure 3. prions 4.Discarding
NCLEX: Clinical Application Read the clinical scenario, and then answer the questions that follow. An OR nurse is responsible for monitoring sterile technique during a surgical procedure. Among her other duties, she ensures that aseptic technique is observed by the medical team and manages the handling of sterile instruments. 1. What is the most appropriate method of sterilization for metallic surgical instruments? 2. During a surgical procedure, the RN observes a surgeon wearing sterile gloves brush his posterior hand surface on a tray. The tray had been cleaned with a liquid chemical agent. What is the most appropriate action by the RN? 3. Which of the following microbes may still be present on sterile surgical instruments? 4. What is the RN's most appropriate action with used needles following the completion of the procedure?
1. Pressurized steam 2.Assertion to the surgeon that a change of gloves is necessary before continuing the procedure 3. prions 4. discarding
Not What We Were Expecting Read the case file and complete the activities that follow. I was working in a pediatric hospital in the emergency room. A 2-year-old girl with an obvious rash was brought in by her mother, who wondered whether the rash might be chickenpox. 1. What is different between each tube when you set up this tube dilution test? 2. How is the minimum inhibitory concentration (MIC) determined from a tube dilution test? 3. Based on your results, what is the MIC for Ceclor against the tested bacterium? 4. If Celcor has a toxic dose of 8 micrograms/milliliter, which would be the therapeutic index (in ratio form) of this drug? 5. Based on your determined therapeutic index, how would the safety of Ceclor compare to an antibiotic with a therapeutic index (in ratio form) of 10/2?
1. The concentration of Ceclor 2. It is the first tube that shows no growth in the series 3. 6.4 micrograms/milliliter 4. 8/6.4 5. It would be more likely to result in serious side effects
Not What We Were Expecting Move the drugs to the correct category based on your understanding of their cellular targets. 1. Ceclor is an antibiotic that targets _______. 2. Cephalosporin antibiotics are derived from the natural products of _______. 3. True or false: The symptoms of Ceclor allergy are due to the immediate quick destruction of a toxic infectious agent. 4. This child has likely been on Ceclor _______. ---------------------------------------- 1. Which of the following drugs targets the cell wall and is responsible for the majority of allergic reactions to antimicrobial drugs? 2. Antibiotics that target the cell wall interfere with the synthesis of _______. 3. If the child was diagnosed with chickenpox as the mother had feared, what would the doctor likely have suggested for the child's Ceclor prescription?
1. cell wall synthesis 2. fungi 3. false 4. at least one time before this infection ----------------------------- 1. Penicillins 2. peptidoglycan 3. Finish the initial course prescribed for the bacterial ear infection
Match the term with its description to test your understanding of microbial control terminology. Match each of the options above to the items below. 1. Sterilization 2. Antisepsis 3. Decontamination 4. Disinfection
1. destruction of microbial life 2. reduction of moist microbial life on living tissue 3. mechanical removal of most microbes from living or inanimate surfaces 4. reduction of most microbial life on inanimate surfaces
Control of Microorganisms in the Operating Room 1. Using a bleach solution to clean the large metals carts in the operating room would have resulted in ______ of the carts. 2. Scrubbing the hands with water and using an alcohol-based hand cleaner is an example of ______. 3. Which of the following methods could have been used for sterilizing the surgical equipment used in this kidney transplant? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.) 4. The sponge used to scrub the surgical site was likely soaked in a(n) ______. 5. After surgery, what methods could have been used to safely dispose of biohazard waste? (NOTE: Please change all question marks to checkmarks for correct answers or empty boxes for incorrect answers.)
1. disinfection 2. antisepsis 3. Ethylene; 35% hydrogen peroxide in chamber; autoclave 4. 2-10% iodophor 5.Autoclave; incinerator
NCLEX: Clinical Application Read the clinical scenario, and then answer the questions that follow. An RN specializing in wound care is performing a dressing change on a leg ulcer for a diabetic patient. The wound is open, tunneled, and exhibiting signs of infection. The RN changes the dressing daily and documents her assessment to track progress towards wound healing. 1. What is the most important action by the RN prior to beginning the dressing change? 2. The RN applies a silver-impregnated dressing to the ulcer. What is the rationale for the use of silver dressings in wound care for this patient? 3. The wound care RN uses hydrogen peroxide in wound cleansing. Which of the following terms best represents the treatment goal with the application of this chemical agent? 4. Which of the following would not be killed by standard-concentration hydrogen peroxide?
1. hand hygiene 2. Silver possesses antimicrobial activity. 3. antisepsis 4. endospores
Preparing the Skin 1. True or False: Based upon the data, irrigation with either sterile saline or tap water results in very low rates of infection in sutured wounds. 2. Based upon your data, which had the smallest rate of wound infection after suturing? 3. Why is this finding significant for your department?
1. true 2. The use of tap water as an irrigant 3. Tap water is easily accessible and inexpensive compared to other agents.
What is an antibiotic?
??
Microbial resistance to drugs is acquired through ______.
All of these are means by which resistance can be transferred between bacteria.
Microbial resistance to drugs is acquired through ______.
All of these are means by which resistance can be transferred between bacteria. conjugation transformation transduction
Treating malarial infections is theoretically difficult because ________.
All of these make malaria difficult to treat.
Treating malarial infections is theoretically difficult because ________.
All of these make malaria difficult to treat. the protozoal parasite is eukaryotic and therefore similar to human cells there are several species of Plasmodium no single drug can target all the life stages of Plasmodium
Disinfection procedures must take into account _________.
All of these must be taken into account.
A reaction that occurs because the drug stimulates the immune system is called a(n) __
Allergic
Pick the true statement about antibiotics.
Antibiotics are natural products of microorganisms.
What are tinctures?
Antimicrobial solutions with alcohol or water-alcohol mixtures as the solvent
Which of the following is not true of an organism's genotype? Is inherited Are structural genes coding for proteins Are genes coding for RNA Are regulatory genes controlling gene expression Are the expressed traits governed by the genes
Are the expressed traits governed by the genes
Three factors that should be considered before beginning antimicrobial therapy are: the nature of the __ causing the infection, its degree of __ to various drugs, and the overall medical condition of the patient.
Blank 1: microbe, microorganism, or pathogen Blank 2: susceptibility, sensitivity, or resistance
A process that deliberately removes genetic material from one organism and combines it with that of a different organism is called __ __ technology
Blank 1: recombinant Blank 2: DNA
Gene therapy leading to changes that are permanent in the individual who is treated, but not passed on to the offspring, is called __ __ gene therapy
Blank 1: somatic Blank 2: cell
Identify the three major modes of action of antiviral drugs.
Blocking virus transcription and translation Barring virus penetration into host cell Preventing virus maturation
A bacterial system that can be used to cause very specific cuts in genes is termed _____.
CRISPR
When bacteriophages invade bacterial cells, they leave behind DNA that is recognized by the bacteria as foreign and can be eliminated in the event of another attack, reminiscent of adaptive immunity. This natural process can be adapted in the lab so that a combination of guide DNA and nucleases facilitate the cutting of DNA at a precise location in any organism. Here we are describing ________.
CRISPR
What is the primary intent of recombinant DNA technology?
Combine genetic material from two organisms
What is cDNA?
DNA made from RNA
Taq polymerase is a ______,
DNA polymerase
Which enzyme builds the new DNA strands in PCR?
DNA polymerase
Match the term with the appropriate description to test your understanding of the diversity of oxygen requirements among microorganisms.
Describes an organism that requires oxygen for growth and has the enzymes to remove toxic by-products of oxygen metabolism Describes an organism that can grow in the presence of oxygen and can detoxify it, but can also grow in the absence of oxygen Describes an organism that cannot grow at normal atmospheric oxygen concentrations, but does require a small amount of oxygen for growth Describes an organism that is unable to use oxygen and lacks the enzymes to detoxify oxygen, thus requiring the absence of oxygen for growth Describes an organism that does not use oxygen, but can grow to a limited extent in the presence of oxygen
The dehydration of microorganisms to inhibit or preserve them is called
Desiccation
A gas that is valuable for sterilization of heat-sensitive objects, such as plastics, surgical and diagnostic appliances, and spices, is ____ oxide. Other related gases are available that are less toxic.
Ethylene
The straining of a fluid or air through a membrane to trap microorganisms is known as
Filtration
What technique is used for separating DNA fragments according to length?
Gel electrophoresis
Match the antibiotic to its description to test your understanding of the different groups of penicillin antibiotics.
Generally most effective against gram-positive bacteria Effective against penicillinase-producing bacteria Broad-spectrum drug, active against gram-positive bacteria and some gram-negative enteric bacteria Added to penicillins to increase effectiveness against resistant bacteria
Which cell can transfer chromosomal and plasmid genes to a recipient cell by conjugation?
Hfr cell
In the stable form of protein, what is generally oriented to the interior of the protein molecule?
Hydrophobic portions
What is the importance of PCR?
Increases the amount of DNA in a sample
If the wild-type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATA ETH EBI GRA T?
Insertion
Which of the following is not true of conjugation?
It transfers genes for a polysaccharide capsule
What is a chemical agent's mode of action?
Its effect on cells
If the wild-type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATE THE BAG RAT?
Missense
If the wild-type DNA sequence reads THE CAT ATE THE BIG RAT, what type of mutation would change the sequence to THE CAT ATE (stop)?
Nonsense
The process occurring in this image is the
PCR
Which bacterial enzyme makes a cell wall inhibitor drug ineffective?
Penicillinase
What type of bonds link individual amino acids together?
Peptide bonds
Which process is occurring in the figure?
Polymerase chain reaction
Which of the following are newer antihelminthic drugs for use in humans?
Praziquantel Ivermectin
Drugs that work for viral infections will target the virus in which of the following ways?
Prevents entry of the virus into host cells Prevents the assembly of new viral particles Do not allow the virus to reproduce inside the cell
Preparations of live microbes used as a preventive or therapeutic measure to displace or compete with potential pathogens are called
Probiotics
______ is the use of a drug to prevent infection of a person at risk.
Prophylaxis
Which of the following drugs was the principal treatment once used for malaria?
Quinine
________ is electromagnetic waves or rays, such as those of light given off from an energy source.
Radiation
What process is illustrated in the figure shown here?
Recombinant DNA for gene cloning
Prions are ______.
Resistant to heat and chemicals
The property of an antimicrobial agent to be highly toxic against its target microbe while being far less toxic to the cells of the host organism is called __ toxicity
Selective
What type of mutation alters the base, but not the amino acid being coded for?
Silent
Which of the following is not associated with a bacterial ribosome?
Small unit provides the enzymes for making peptide bonds
Looking at the data in this table, this bacterial population is likely in what growth phase between 20 and 24 hours?
Stationary phase
What is desiccation?
The dehydration of microbes for preservation
Which of the following are the three factors that should be known before selecting an antimicrobial drug?
The nature of the infecting agent The sensitivity of the infecting agent The overall health of the patient
What factors should be known before administering antimicrobial therapy to a patient?
The nature of the microorganism causing the infection. The sensitivity of the microorganism to various drugs. The overall medical condition of the patient.
When an egg is fried, what happens to the protein in the egg?
The protein is denatured.
The ratio of the toxic dose to the effective dose that is used to assess the safety and reliability of a drug is called the __ __
Therapeutic index
A drug that is effective against more than one group of bacteria is known as a ___ -spectrum antimicrobial.
broad
Which of the following are the categories of major drug side effects?
Toxic damage to tissue Normal flora disruption Allergic reactions
Microbes can associate with other organisms in a variety of different relationships. Please match the association to its most correct description.
Two organisms living together in which both partners benefit from the relationship Two organisms living together in which one organism benefits and the other is neither benefited nor harmed Two organisms living together in which one organism benefits and the other (the host) is harmed A relationship in which free-living organisms cooperate and share nutrients A competitive relationship between free-living organisms in which one organism secretes substances that are toxic to the other, in order to acquire more space or nutrients for itself
Transcription is targeted most directly by _______.
UV Radiation
DNA repair mechanisms can help alleviate the effects of _______.
UV radiation
Which type of drug is effective against more than one group of bacteria?
broad-spectrum
Which of the growth curves represents an obligate aerobe grown in the presence of oxygen? -a Which of the growth curves represents an obligate anaerobe grown in the presence of oxygen? -c Which of the growth curves represents an aerotolerant anaerobe grown in the presence of oxygen? -b Which of the growth curves represents a facultative anaerobe grown in the presence of oxygen? -a
a
Bacterial conjugation involves ________.
a donor cell with a plasmid that synthesizes a pilus
Which of these items are considered critical for sterilization?
a syringe needle an artificial hip
Eukaryotic chromosomes differ from bacterial chromosomes because only eukaryotes have ________.
all- histone proteins chromosomes in a nucleus several to many chromosomes elongated, not circular, chromosomes
A drug ______ occurs when a drug acts as an antigen and stimulates an immune response.
allergy
A drug reaction that occurs because the drug stimulates the immune system is known as a(n) _____.
allergy
Three consecutive bases in the DNA of a gene represent the code for one _______.
amino acid
Dry heat occurs in the forms of ______ and ______.
an open flame hot air oven
A compound synthesized by bacteria or fungi that destroys or inhibits the growth of other microbes is a(n) ________.
antibiotic
A natural metabolic product produced by bacteria and fungi to reduce competition for nutrients and space in their habitat is a(n) ______.
antibiotic
a(n) _ is an antimicrobial produced by natural metabolic processes of some microorganisms that can inhibit or kill other microorganisms.
antibiotics
a(n) ____ is an antimicrobial produced by natural metabolic processes of some microorganisms that can inhibit or kill other microorganisms.
antibiotics
Which of the following is not true of transposons?
are always part of plasmids
A ______ agent will inhibit the growth of bacteria, whereas a ______ agent will kill bacteria.
bacteristatic; bactericidal
What are biota?
beneficial or harmless microbial residents of the human body
Antimicrobial drugs often cannot penetrate the sticky extracellular material surrounding organisms in a ___
biofilm
The normal colonists of the human body, mostly harmless or beneficial bacteria, are called the ______.
biota
Moist heat occurs in the forms of ______ and ______.
boiling water steam
A desirable characteristic of a germicide is __ spectrum action.
broad
Antimicrobial drug damage ______.
can be permanent or reversible
A type of recombinant DNA technology procedure which involves removing a selected gene of interest from an animal, plant, or microorganism and then inserting and propagating it within a different host organism is known as _________.
cloning
A three base sequence on mRNA is called a(n) _______.
codon
What is the primary intent or recombinant DNA technology?
combine the genetic material form two organisms
DNA that is made from RNA is called __ DNA
complementary
The current diseases that might prove curable by gene therapy are those like ______.
cystic fibrosis, which is the result of a mutation in a single gene
The phenomenon that involves the permanent termination of an organism's vital processes is
death
______ involves the permanent termination of a particular organism's vital processes, and special qualifications are often needed to define and delineate this phenomenon in microbes.
death
Match the term with its description to test your understanding of microbial control terminology.
disinfection- Reduction of most microbial life on inanimate surfaces Sterilization-Destruction of all microbial life including bacterial endospores Decontamination-Mechanical removal of most microbes from living or inanimate surfaces Antisepsis-Reduction of most microbial life on living tissue
Ethylene oxide typically kills microbes by ______.
disrupting enzyme function blocking DNA replication
Ethylene oxide typically kills microbes by blocking __ replication and enzymatic actions.
dna
Microbial control methods that kill ______ are able to sterilize.
endospores
Which chemical is valuable for sterilization of heat-sensitive objects such as plastics, surgical and diagnostic appliances, and spices, but is more toxic than other available related gases?
ethylene oxide
Antifungal agents are often toxic to host cells because the fungal and the host cells are both __
eukaryotic
true false: The lagging strand of DNA is made in small segments called Okazaki fragments, each one requiring a primer to begin synthesis, whereas the leading strand, synthesized continuously, does not require a primer to initiate the daughter strand.
false ??
true false: all mutations are detrimental to the cell.
false ??
Straining of air or fluid through a membrane with openings too small for microorganisms to pass through is called ______.
filtration
The most versatile method for sterilizing heat-sensitive liquids is _______.
filtration
the most versatile method for sterilizing heat-sensitive liquids is _______.
filtration
The most serious type of mutation is a ________.
frameshift mutation
A method for separating DNA fragments of different lengths is ______.
gel electrophoresis
This image shows DNA fragments separated by ______.
gel electrophoresis
Which technique is portrayed in the image?
gel electrophoresis
A specific segment of DNA that contains the necessary code to make a protein or RNA molecule is a __________.
gene
Each _______ is a specific segment of the DNA with the code for production of one functional product.
gene
The replacement of a faulty gene responsible for a disease with the wild type gene is termed ______.
gene therapy
A bacteriophage transfers DNA of the previous host to the current host. This is an example of ________.
generalized transduction
Biofilm bacteria are not affected in the same way as their free-living counterparts by antibiotics because biofilm bacteria express different ___ and therefore have different antibiotic sensitivities.
genes
The _____ is all of the genetic material of a cell.
genome
The sum total of genetic material of a cell is referred to as its ________.
genome
The genetic makeup of an organism is referred to as its ________, whereas the observable traits are referred to as its ________.
genotype; phenotype
Changes to the genome of an individual that are passed on to offspring are termed _____ therapy.
germline
Which is incorrect about inducible operons?
have genes turned off by a buildup of end product
Prions are extraordinarily resistant to inactivation by _ and chemicals
heat
The most prominent antimicrobial physical agent is ______.
heat
Which of the following is the most common physical agent used to control microbes?
heat
An antimicrobial drug with a _______ therapeutic index is a better choice than one with a _______ therapeutic index.
high; low
Base pairs in DNA are held together by _______ bonds.
hydrogen
Preparing the Skin Several types of germicides are used in skin preparation based on the specific situation. Move the labels to the correct category to demonstrate your understanding of these different germicidal groups.
hydrogen halogens alcohols chlorhexidine
Plasmolysis of bacteria in foods occurs when high concentrations of salt or sugar are added to the foods creating a __ environment
hypertonic
The use of sugar or salt to preserve food creates a __ environment for the bacteria in the foods.
hypertonic
Match the environment with the effects of a cell placed in that environment to test your understanding of the tonicity terms.
hypertonic- A cell in this environment will lose water and shrink as water moves out of the cell by osmosis. hypotonic- A cell in this environment will swell as water moves in by osmosis, and may lyse if it does not have a cell wall. isotonic-a cell in this environ will neither shrink nor swell as there is no net movement of water
Which of the following is incorrect about termination codons?
include aug
Which of the following is incorrect about transfer RNA?
iniatiator tRNA in bacteria carries tryptophan
A combination of iodine and an organic carrier (such as alcohol) that serves as a moderate-level disinfectant and antiseptic is a(n)
iodophor
Complexes of iodine and alcohol are called
iodophors
Nephrotoxic drugs are toxic to the ______.
kidneys
Quinine is a drug used to treat
malaria
The CDC is monitoring the spread of the ______ gene among bacterial species because it makes cells resistant to polymyxin, an antibiotic used to treat infections by bacteria that are resistant to multiple drugs.
mcr-1
Three factors that should be considered before beginning antimicrobial therapy are: the nature of the ____ causing the infection, its degree of ____ to various drugs, and the overall medical condition of the patient.
microorganism susceptibility
The smallest concentration of a drug that visibly inhibits the growth of a microorganism is called the ______ concentration.
minimum inhibitory
The lowest concentration of a drug that visibly inhibits growth is called the , ___ ___ ___ or MIC.
minimum inhibitory concentration
An agent's effect on cells is known as its _ of action
mode
An agent's effect on cells is known as its __ of action.
mode
Which molecule is synthesized as a copy of a gene on the DNA template strand?
mrna
A mutation that changes a normal codon to a stop codon is called a ________.
nonsense mutation
All of the following pertain to transcription except ________.
occurs on a ribosome in the cytoplasm
The antiparallel arrangement within DNA molecules refers to ________.
one helix strand that runs from the 5' to 3' direction and the other strand runs from the 3' to 5' direction
Each nucleotide is composed of ________.
one phosphate, one nitrogenous base, and one sugar.
The following pertain to ribosomes during protein synthesis except ________.
participate in both transcription and translation
Match the antibiotic to its description to test your understanding of the different groups of penicillin antibiotics.
penicillin g and v- Generally most effective against gram-positive bacteria nafcillin-Effective against penicillinase-producing bacteria ampicillin-Broad-spectrum drug, active against gram-positive bacteria and some gram-negative enteric bacteria clavulanic acid-Added to penicillins to increase effectiveness against resistant bacteria
An enzyme that hydrolyzes penicillin and is found in penicillin-resistant strains of bacteria is called __
penicillinase
Drugs that prevent the formation of the bacterial cell wall are _______.
penicillins
Which term refers to bacteria that slow or stop their metabolism so that they cannot be harmed by an antibiotic?
persisters
Move the correct essential nutrient next to its best description based on your understanding of the roles of these nutrients.
phosphate- A cell is unable to produce ATP and its cell membrane has lost its integrity because of a deficiency of this nutrient nitrogen- A cell is unable to synthesize proteins and nucleic acids due to a deficiency in this essential nutrient required for their structure sulfur- A cell's proteins are misshapen or unstable because of its lack of the amino acids cysteine and methionine (composed in part by this nutrient) oxygen- This nutrient is a major part of all organic compounds in the cell as well as water, the major component of the cell hydrogen- A cell requires this nutrient for pH maintenance and the bonds between DNA strands carbon-A fundamental component of organic molecules consumed by and produced by the cell
Move the terms to their correct descriptions to review the various nutritional categories of microbes.
photoautotroph- Uses sunlight as an energy source and carbon dioxide as a carbon source (example: cyanobacteria) chemoautoph- Uses simple inorganic compounds for energy and carbon dioxide for a carbon source (example: methanogens) photoheterotroph- Uses sunlight as an energy source and an organic carbon source (example: purple photosynthetic bacteria) chemoheterotroph- Converts nutrients from other organisms into energy and uses an organic carbon source (example: protozoa) saphrobe- Metabolizes organic matter of dead organisms for energy and uses an organic carbon source (example: fungi) parasite- Utilizes the tissues of a live host and an organic carbon source (example: pathogens)
Summarize the problems that have led to the worldwide problem of managing antimicrobial drugs.
physicians use a "shotgun" approach to treat minor infections increase in superinfections development of resistance in "bystander" microbes
R factors are _______ that contain a code for _______.
plasmids; drug resistance
A method for making billions of copies of a specific DNA sequence is ______.
polymerase chain reaction PCR
A concerning development is the identification of the mcr-1 gene which renders bacteria resistant to the last-resort antibiotic ______.
polymyxin
Which are preparations of live microbes used as a preventive or therapeutic measure to displace or compete with potential pathogens?
probiotics
The nontranscribed region of DNA to which RNA polymerase binds to initiate transcription is called the _______.
promoter
The use of a drug to prevent imminent infection of a person at risk is called
prophylaxis
Which term refers to the use of a drug to prevent imminent infection of a person at risk?
prophylaxis
Match the term with the appropriate description to test your understanding of terminology regarding temperature preferences of microorganisms.
psychrophile- Describes an organism that grows optimally at temperatures ranging from 0°C to 15°C pyschrotolerant- Describes an organism that has an optimum growth temperature between 15°C and 30°C, but is able to grow slowly at colder temperatures mesophile-Describes an organism that grows optimally at temperatures ranging from 20°C to 40°C thermophile-Describes an organism that grows optimally at temperatures ranging from 45°C to 80°C hyperthermophile-Describes an organism that grows optimally at temperatures ranging from 80°C to 120°C
Energy emitted from atomic activities and dispersed at high velocity through matter or space is called
radiation
Which term refers to energy emitted from atomic activities and dispersed at high velocity through matter or space?
radiation
The gene that codes for a protein capable of repressing an operon is called the _______.
regulator
The duplication of a cell's DNA is called _______.
replication
An adaptive response in which microorganisms begin to tolerate an amount of drug that would ordinarily be inhibitory is called drug ______.
resistance
The enzyme that can convert RNA into DNA is called
reverse transcriptase
For DNA replication, a primer of ________ is needed at the origin of nucleotide addition.
rna
The helix that forms in a protein chain as a result of hydrogen bonds and other weak forces is an example of ________.
secondary structure of protein
A drug that kills or inhibits microbial cells without simultaneously damaging host tissues is called ______ toxic.
selectively
Devices that come into contact with mucosal membranes are called ______.
semicritical
When forming a semisolid gel such as gelatin, what type of molecule does the process of protein coagulation entrap?
water