The study of viruses is ___________.virology25.
The cells of prokaryotic organisms lack a _______.nucleus7.
Which of the following terms refers to a prokaryotic cell that is comma shaped?
spirillumvibrio8. Which bacterial structures are important for adherence to surfaces? (Select all that apply.)
capsules9. Which of the following cell wall components is unique to gram-negative cells?
peptidoglycanlipopolysaccharide10. Which of the following terms refers to a bacterial cell having a single tuft of flagella at one end?
lophotrichouslophotrichous11. Bacterial cell walls are primarily composed of which of the following?
peptidoglycanpeptidoglycan12. Which of the following organelles is not part of the endomembrane system?
peroxisomeperoxisome13. Which type of cytoskeletal fiber is important in the formation of the nuclear lamina?
fibronectinintermediate filaments14. Sugar groups may be added to proteins in which of the following?
smooth endoplasmic reticulum
rough endoplasmic reticulum
lysosomeGolgi apparatus15. Which of the following structures of a eukaryotic cell is not likely derived from endosymbiotic bacterium?
outer membraneouter membrane16. Which type of nutrient uptake involves the engulfment of small dissolved molecules into vesicles?
facilitated diffusionpinocytosis17. Which of the following is not composed of microtubules?
Exposure to air is necessary for microbial growth. (False)False19.
Bacteria have 80S ribosomes each composed of a 60S large subunit and a 40S small subunit.False20.
Mitochondria in eukaryotic cells contain ribosomes that are structurally similar to those found in prokaryotic cells.True25.
Prokaryotic cells that are rod-shaped are called _____________.bacilli26.
The type of inclusion containing polymerized inorganic phosphate is called _____________.volutin (or metachromatic granule)27.
Peroxisomes typically produce _____________, a harsh chemical that helps break down molecules.hydrogen peroxide28.
Microfilaments are composed of _____________ monomers.. actin1. The term prokaryotes refers to which of the following?
very small organisms
unicellular organisms that have no nucleus
cells that resemble animal cells more than plant cellsunicellular organisms that have no nucleus2. The term microbiota refers to which of the following?
all microorganisms of the same species
all of the microorganisms involved in a symbiotic relationship
all microorganisms in a certain region of the human body
all microorganisms in a certain geographic regionall microorganisms in a certain region of the human body3. Which of the following refers to the type of interaction between two prokaryotic populations in which one population benefits and the other is not affected?
neutralismcommensalism4. Which of the following describes Proteobacteria in domain Bacteria?
genusphylum14. Archaea and Bacteria are most similar in terms of their ________.
cell wall structure
unicellular structureunicellular structure15. Which of the following is true of archaea that produce methane?
They reduce carbon dioxide in the presence of nitrogen.
They live in the most extreme environments.
They are always anaerobes.
They have been discovered on Mars.They live in the most extreme environments.16.
Among prokaryotes, there are some that can live in every environment on earth.True17.
When prokaryotes live as interacting communities in which one population benefits to the harm of the other, the type of symbiosis is called ________.parasitism18.
The domain ________ does not include prokaryotes.Eukarya19.
Pathogenic bacteria that are part of the transient microbiota can sometimes be eliminated by ________ therapy.antibiotic20. Nitrogen-fixing bacteria provide other organisms with usable nitrogen in the form of ________.ammonia33.
________ is a genus of Archaea. Its optimal environmental temperature ranges from 70 °C to 80 °C, and its optimal pH is 2-3. It oxidizes sulfur and produces sulfuric acid.Sulfolobus34.
________ was once thought to be the cause of periodontal disease, but, more recently, the causal relationship between this archaean and the disease was not confirmed.Methanobrevibacter oralis1. Which genus includes the causative agent for malaria?
TrypanosomaPlasmodium2. Which protist is a concern because of its ability to contaminate water supplies and cause diarrheal illness?
Trichomonas vaginalisGiardia lamblia3. A fluke is classified within which of the following?
AnnelidaPlatyhelminthes4. A nonsegmented worm is found during a routine colonoscopy of an individual who reported having abdominal cramps, nausea, and vomiting. This worm is likely which of the following?
annelidnematode5. A segmented worm has male and female reproductive organs in each segment. Some use hooks to attach to the intestinal wall. Which type of worm is this?
annelidcestode6. Mushrooms are a type of which of the following?
basidiocarpbasidiocarp7. Which of the following is the most common cause of human yeast infections?
Aspergillus fumigatusCandida albicans8. Which of the following is an ascomycete fungus associated with bat droppings that can cause a respiratory infection if inhaled?
Trichophyton rubrumHistoplasma capsulatum15.
The plasma membrane of a protist is called the __________.plasmalemma16.
Animals belong to the same supergroup as the kingdom __________.Fungi17.
Flukes are in class _________.Trematoda18.
A species of worm in which there are distinct male and female individuals is described as _________.dioecious20.
Unicellular fungi are called _________.yeasts19.
Nonseptate hyphae are also called _________.coenocytic21.
Some fungi have proven medically useful because they can be used to produce _________.antibiotics1.
The component(s) of a virus that is/are extended from the envelope for attachment is/are the:
Which of the following does a virus lack? Select all that apply.
The envelope of a virus is derived from the host's
In naming viruses, the family name ends with ________ and genus name ends with _________.
−virus; virion−viridae; −virus5.
What is another name for a nonenveloped virus?
latent virusnaked virus6.
Which of the following leads to the destruction of the host cells?
temperate phagelytic cycle7.
A virus obtains its envelope during which of the following phases?
Which of the following components is brought into a cell by HIV?
a DNA-dependent DNA polymerase
reverse transcriptasereverse transcriptase9.
A positive-strand RNA virus:
must first be converted to a mRNA before it can be translated.
can be used directly to translate viral proteins.
will be degraded by host enzymes.
is not recognized by host ribosomes.can be used directly to translate viral proteins.10.
What is the name for the transfer of genetic information from one bacterium to another bacterium by a phage?
Which of the followings cannot be used to culture viruses?
liquid medium only
animal hostliquid medium only12.
Which of the following tests can be used to detect the presence of a specific virus?
all of the aboveall of the above13.
Which of the following is NOT a cytopathic effect?
inclusion bodiesmononucleated cell14.
Which of these infectious agents do not have nucleic acid?
Which of the following is true of prions?
They can be inactivated by boiling at 100 °C.
They contain a capsid.
They are a rogue form of protein, PrP.
They can be reliably inactivated by an autoclave.They are a rogue form of protein, PrP.16.
True or False: Scientists have identified viruses that are able to infect fungal cells.True17.
A virus that infects a bacterium is called a/an ___________________.bacteriophage18.
A/an __________ virus possesses characteristics of both a polyhedral and helical virus.complex19.
A virus containing only nucleic acid and a capsid is called a/an ___________________ virus or __________________ virus.naked or nonenveloped20.
The ____________ _____________ on the bacteriophage allow for binding to the bacterial cell.tail fibers21.
An enzyme from HIV that can make a copy of DNA from RNA is called _______________________.reverse transcriptase22.
For lytic viruses, _________________ is a phase during a viral growth curve when the virus is not detected.eclipse23.
Viruses can be diagnosed and observed using a(n) _____________ microscope.23. Electron24.
Cell abnormalities resulting from a viral infection are called ____________ _____________.cytopathic effects25.
Both viroids and virusoids have a(n) _________ genome, but virusoids require a(n) _________ to reproduce.RNA, helper virusName each labeled part of the illustrated bacteriophage.36.
Label the five stages of a bacteriophage infection in the figure:Label the components indicated by arrows.1.
Which of the following types of medical items requires sterilization?
blood pressure cuffsneedles2.
Which of the following is suitable for use on tissues for microbial control to prevent infection?
Which biosafety level is appropriate for research with microbes or infectious agents that pose moderate risk to laboratory workers and the community, and are typically indigenous?
Which of the following best describes a microbial control protocol that inhibits the growth of molds and yeast?
The decimal reduction time refers to the amount of time it takes to which of the following?
reduce a microbial population by 10%
reduce a microbial population by 0.1%
reduce a microbial population by 90%
completely eliminate a microbial populationreduce a microbial population by 90%6.
Which of the following methods brings about cell lysis due to cavitation induced by rapid localized pressure changes?
Which of the following terms is used to describe the time required to kill all of the microbes within a sample at a given temperature?
thermal death point
thermal death time
decimal reduction timethermal death time8.
Which of the following microbial control methods does not actually kill microbes or inhibit their growth but instead removes them physically from samples?
Which of the following refers to a disinfecting chemical dissolved in alcohol?
Which of the following peroxygens is widely used as a household disinfectant, is inexpensive, and breaks down into water and oxygen gas?
Which of the following chemical food preservatives is used in the wine industry but may cause asthmatic reactions in some individuals?
Bleach is an example of which group of chemicals used for disinfection?
Which chemical disinfectant works by methylating enzymes and nucleic acids and is known for being toxic and carcinogenic?
Sanitization leaves an object free of microbes.False18.
Ionizing radiation can penetrate surfaces, but nonionizing radiation cannot.True19.
Moist-heat sterilization protocols require the use of higher temperatures for longer periods of time than do dry-heat sterilization protocols do.False20.
Soaps are classified as disinfectants.False21.
Mercury-based compounds have fallen out of favor for use as preservatives and antiseptics.True22.
A medical item that comes into contact with intact skin and does not penetrate sterile tissues or come into contact with mucous membranes is called a(n) ________ item.noncritical23.
The goal of ________ ________ protocols is to rid canned produce of Clostridium botulinum endospores.commercial sterilization24.
In an autoclave, the application of pressure to ________ is increased to allow the steam to achieve temperatures above the boiling point of water.steam25.
Doorknobs and other surfaces in clinical settings are often coated with ________, ________, or ________ to prevent the transmission of microbes.copper, nickel, zinc1.
Which of the following would be a sign of an infection?
Which of the following is an example of a noncommunicable infectious disease?
infection with a respiratory virus
food poisoning due to a preformed bacterial toxin in food
skin infection acquired from a dog bite
infection acquired from the stick of a contaminated needlefood poisoning due to a preformed bacterial toxin in food3.
During an oral surgery, the surgeon nicked the patient's gum with a sharp instrument. This allowed Streptococcus, a bacterium normally present in the mouth, to gain access to the blood. As a result, the patient developed bacterial endocarditis (an infection of the heart). Which type of disease is this?
Which period is the stage of disease during which the patient begins to present general signs and symptoms?
A communicable disease that can be easily transmitted from person to person is which type of disease?
Which of the following is a pathogen that could not be identified by the original Koch's postulates?
Human immunodeficiency virus
Salmonella enterica serovar TyphimuriumHuman immunodeficiency virus7.
Pathogen A has an ID50 of 50 particles, pathogen B has an ID50 of 1,000 particles, and pathogen C has an ID50 of 1 × 106 particles. Which pathogen is most virulent?
pathogen Cpathogen A8.
Which of the following choices lists the steps of pathogenesis in the correct order?
invasion, infection, adhesion, exposure
adhesion, exposure, infection, invasion
exposure, adhesion, invasion, infection
disease, infection, exposure, invasionexposure, adhesion, invasion, infection9.
Which of the following would be a virulence factor of a pathogen?
a surface protein allowing the pathogen to bind to host cells
a secondary host the pathogen can infect
a surface protein the host immune system recognizes
the ability to form a provirusa surface protein allowing the pathogen to bind to host cells10.
You have recently identified a new toxin. It is produced by a gram-negative bacterium. It is composed mostly of protein, has high toxicity, and is not heat stable. You also discover that it targets liver cells. Based on these characteristics, how would you classify this toxin?
Which of the following applies to hyaluronidase?
It acts as a spreading factor.
It promotes blood clotting.
It is an example of an adhesin.
It is produced by immune cells to target pathogens.It acts as a spreading factor.12.
Phospholipases are enzymes that do which of the following?
promote pathogen spread through connective tissue.
degrade nucleic acid to promote spread of pathogen
degrade cell membranes to allow pathogens to escape phagosomesdegrade cell membranes to allow pathogens to escape phagosomes13.
Which of the following is a major virulence factor for the fungal pathogen Cryptococcus?
Which of the following pathogens undergoes antigenic variation to avoid immune defenses?
A difference between an acute disease and chronic disease is that chronic diseases have an extended period of __________.illness16.
A person steps on a rusty nail and develops tetanus. In this case, the person has acquired a(n) __________ disease.noncommunicable17.
A(n) __________ pathogen causes disease only when conditions are favorable for the microorganism because of transfer to an inappropriate body site or weakened immunity in an individual.opportunistic18.
The concentration of pathogen needed to kill 50% of an infected group of test animals is the __________.LD5019.
A(n) __________ infection is a small region of infection from which a pathogen may move to another part of the body to establish a second infection.focal20.
Cilia, fimbriae, and pili are all examples of structures used by microbes for __________.adhesion21.
The glycoprotein adhesion gp120 on HIV must interact with __________ on some immune cells as the first step in the process of infecting the cell.CD422.
Adhesins are usually located on __________ of the pathogen and are composed mainly of __________ and __________.surface; proteins; sugars23.
The Shiga and diphtheria toxins target __________ in host cells.protein synthesis24.
Antigenic __________ is the result of reassortment of genes responsible for the production of influenza virus spike proteins between different virus particles while in the same host, whereas antigenic __________ is the result of point mutations in the spike proteins.shift; drift25.
Candida can invade tissue by producing the exoenzymes __________ and __________.protease and phospholipase26.
The larval form of Schistosoma mansoni uses a __________ to help it gain entry through intact skin.protease1.
Which is the most common type of biological vector of human disease?
A mosquito bites a person who subsequently develops a fever and abdominal rash. What type of transmission would this be?
mechanical vector transmission
biological vector transmission
direct contact transmission
vehicle transmissionbiological vector transmission3.
Cattle are allowed to pasture in a field that contains the farmhouse well, and the farmer's family becomes ill with a gastrointestinal pathogen after drinking the water. What type of transmission of infectious agents would this be?
biological vector transmission
direct contact transmission
indirect contact transmission
vehicle transmissionvehicle transmission4.
A blanket from a child with chickenpox is likely to be contaminated with the virus that causes chickenpox (Varicella-zoster virus). What is the blanket called?
Which of the following would NOT be considered an emerging disease?
Ebola hemorrhagic fever
West Nile virus fever/encephalitis
Zika virus disease
Which of the following would NOT be considered a reemerging disease?
West Nile virus fever/encephalitisWest Nile virus fever/encephalitis7.
Which of the following factors can lead to reemergence of a disease?
A mutation that allows it to infect humans
A period of decline in vaccination rates
A change in disease reporting procedures
Better education on the signs and symptoms of the diseaseA period of decline in vaccination rates8.
Why are emerging diseases with very few cases the focus of intense scrutiny?
They tend to be more deadly
They are increasing and therefore not controlled
They naturally have higher transmission rates
They occur more in developed countriesThey are increasing and therefore not controlled15.
A patient in the hospital with a urinary catheter develops a bladder infection. This is an example of a(n) ________ infection.nosocomial or healthcare-associated16.
A ________ is an animal that can transfer infectious pathogens from one host to another.vector