micro ex 1 practice questions
A clinical laboratory that identifies the bacterial agents that cause human disease would refer to Bergey's Manual of______ Bacteriology for guidance in identification. A. Systematic B. Determinative C. Classical D. Evolutionary
B. Determinative
A patient has a serious respiratory infection. A sputum sample yielded a bacterium that did not have any peptidoglycan. You hypothesize that the identity of this microbe could possibly be _______. A. Streptococcus pneumoniae B. Mycobacterium tuberculosis C. Borrelia burgdorferi D. Staphylococcus aureus E. Mycoplasma pneumoniae
E. Mycoplasma pneumoniae
25. Which of the following is produced by adding 1% to 5% agar to nutrient broth that is then boiled and cooled? A. A pure culture B. A contaminated medium C. A liquid medium D. A mixed culture E. A solid medium
E. a solid medium
Mycobacterium and Nocardia are distinguished from other bacteria by the ______ stain. A. endospore B. basic C. methylene blue D. Gram E. acid-fast
E. acid-fast
Fungal asexual spores A. produce offspring with different combinations of genes from the parent. B. cannot be seen using a light microscope. C. are produced when nutrients are limiting. D. are the products of meiotic division by a single parent cell. E. are used to identify fungi.
E. are used to identify fungi
If bacteria living in salty seawater were displaced to a freshwater environment, the cell structure that would prevent the cells from rupturing is the ______. A. slime layer B. capsule C. endospore D. cell membrane E. cell wall
E. cell wall
26. Chemical analysis of a bacterial cell detects dipicolinic acid. What is the identity of this structure? A. Nucleoid B. Cell wall C. Biofilm D. Capsule E. Endospore
E. endospore
Which pair is mismatched? A. Histoplasma - causes Ohio Valley fever B. Giardia - transmitted by feces in drinking water C. Trichomonas - sexually transmitted D. Trypanosoma - causes African sleeping sickness E. Plasmodium - causes Chagas disease
E. Plasmodium - causes Chagas disease
Alcohol-based hand sanitizers specifically target lipids, making them most effective when trying to eliminate A. endospores B. biofilms C. gram-positives D. viruses E. gram-negatives
E. gram-negatives
Protozoan endoplasm contains ______. A. cilia B. oral grooves C. ectoplasm D. flagella E. mitochondria
E. mitochondria
Which type of microscopy transforms the subtle variations in cell density into differences in light intensity, and for increased internal detail without staining? A. Electron B. Fluorescence C. Bright-field D. Confocal E. Phase-contrast
E. phase-contrast
Viral growth in bird embryos can cause discrete, opaque spots in the embryonic membranes called ______. A. patches B. buds C. plaques D. cytopathic effects E. pocks
E. pocks
Viruses are considered ultramicroscopic because they range in size from 2 mm to 450 mm. True or False
False (range 20-200nm)
Which of the following does not pertain to endotoxin? A. Endotoxin can cause septic shock in the human body. B. Endotoxin is found in acid-fast bacterial cell walls. C. Endotoxin can stimulate fever in the human body. D. Endotoxin is a bacterial cell wall lipid.
B. Endotoxin in found in acid-fast bacterial cell walls. (it is actually found in gram negatives)
30. All of the following structures contribute to the ability of pathogenic bacteria to cause disease except ______. A. gram-negative outer membrane B. inclusions C. slime layer D. capsule E. fimbriae
B. inclusions
T-even phages ______. A. include the poxviruses B. infect Escherichia coli cells C. enter host cells by engulfment D. have helical capsids
B. infect Escherichia coli cells
75. The term that refers to the presence of a tuft of flagella emerging from a single site is ______. A. amphitrichous B. lophotrichous C. atrichous D. peritrichous E. monotrichous
B. lophotrichous
Oncogenic viruses include all the following except ______. A. hepatitis B virus B. measles virus C. Papillomavirus D. HTLV-I and HTLV-II viruses E. Epstein-Barr virus
B. measles virus
If you observe rod-shaped, pink cells on a slide that had just been Gram stained, you can assume that their cell envelop contains endotoxin. T or F
True
Many chronic medical conditions have been found to be associated with microbial agents. True/False
True
Using species names for viruses is controversial since viruses are not considered living organisms, and they change over time so characteristics that may be used for speciation are unstable. True False
True
61. Hot carbol fuchsin is the primary dye in the acid-fast stain. True or False
True
Which of the following organisms has a cell wall? A. Candida albicans B. Entamoeba histolytica C. Enterobius vermicularis D. Trypanosoma cruzi
A. Candida albicans
Which type of microscope does not use light in forming the specimen image? A. Electron B. Dark-field C. Phase-contrast D. Bright-field E. Fluoresce
A. Electron
Which of the following statements regarding chemotaxis is incorrect? A. In a cell with peritrichous flagella, each flagellum moves individually but in a coordinated direction during a run. B. In a tumble, the flagellum reverses direction, causing the cell to stop moving and change course. C. When a cell detects a nutrient gradient, it will increase the frequency of runs to move toward the nutrient. D. The fuel for flagellar motion is not ATP, but a proton gradient.
A. In a cell with peritrichous flagella, each flagellum moves individually but in a coordinated direction during a run.
A group of protozoa that are not motile are the ______. A. Plasmodium sp. B. ciliates C. amoebas D. dimorphics E. trophozoites
A. Plasmodium sp.
Humans can see objects as small as 0.1mm. Leeuwenhoek's best microscope could magnify objects to 300x. Which of the following would be invisible using Leeuwenhoek's microscope? A. Poliovirus, 30 nm B. Red blood cell, 8 mm C. Escherichia coli, 1 mm X 4 mm D. Pandora virus, 0.5 mm X 1 mm
A. Poliovirus, 30nm
Which of the following is mismatched? A. Tenericutes - waxy, acid-fast cell walls B. Gracilicutes - gram-negative cell walls C. Mendosicutes - archaea cell walls D. Firmicutes - gram-positive cell walls
A. Tenericutes - waxy, acid-fast cell walls
75. Protozoan cysts are A. analogous to bacterial endospores. B. part of all protozoan life cycles. C. the primary form of replication. D. necessary for transmission to a new host. E. are produced by binary fission.
A. analogous to bacterial endospores
38. The site for ATP synthesis in bacterial cells is the ______. A. cell membrane B. mitochondrion C. cell wall D. microcompartment E. ribosome
A. cell membrane
87. Bacterial cells could have any of the following appendages except ______. A. cilia B. fimbriae C. periplasmic flagella (axial filaments) D. flagella E. pili
A. cilia
48. The drug cytochalasin targets actin filaments in the cytoskeleton, preventing them from forming. Treatment of a cell with cytochalasin would result in its inability to ______. A. form cellular extensions B. transport substances within the cell C. form the nuclear envelope structure D. prevent mutations in its chromosome
A. form cellular extensions
The division of microbes termed the Firmicutes have a cell wall type best described as ______. A. gram-positive B. archaeal C. lacking a cell wall D. gram-negative
A. gram-positive
Cells grown in culture form a/an ______. A. monolayer B. bilayer C. aggregate D. plaque
A. monolayer
In order to replicate within a host cell, a virus with a genome comprised of single-stranded positive-sense RNA A. must use its genomic strand as a template to make copies of negative-sense RNA for packaging. B. must use its genomic strand as a template to make copies of positive-sense RNA for packaging. C. must first use its genomic strand as a template to make a negative-sense RNA, which then serves as a template to synthesize positive-sense RNA for packaging. D. must first use its genomic strand as a template to make copies of DNA for packaging.
A. must use its genomic strand as a template to make copies of negative-sense RNA for packaging
75. The term that refers to the presence of flagella all over the cell surface is ______. A. peritrichous B. lophotrichous C. monotrichous D. atrichous E. amphitrichous
A. peritrichous
Which of the following is essential for the development of discrete, isolated colonies? A. Solid medium B. Differential medium C. Broth medium D. Assay medium E. Selective medium
A. solid medium
Serological analysis for bacterial identification typically involves using: A. specific antibodies to the bacterial cell antigens. B. a microscope to determine cell morphology. C. the determination of guanine + cytosine base concentrations. D. methods to identify cell enzymes. E. the analysis of the appearance of colonies.
A. specific antibodies to the bacterial cell antigens
A research laboratory that identifies the subspecies of bacterial isolates from a recent Salmonella epidemic would refer to Bergey's Manual of ______ Bacteriology for guidance in identification. A. Systematic B. Classical C. Evolutionary D. Determinative
A. systematic
Select that statement that reflects evidence that directly supports the endosymbiotic theory. A. The electron transport system is located in the cell membrane in bacteria, while in eukaryotes it is located in the mitochondrial cristae. B. Enzymes for photosynthesis are found embedded in membranes of the Golgi apparatus. C. Lysosomes contain their own DNA in the form of plasmids. D. Glycolysis occurs in the cytoplasm of bacterial cells.
A. the electron transport system is located in the cell membrane in bacteria, while in eukaryotes it is located in the mitochondrial cristae
Cells of Staphylococcus aureus are cocci measuring about 1 um in diameter. In a textbook image of S. aureus each cell measures about 1 cm. The magnification of the image on the page is: A. 10,000X B. 1,000X C. 100X D. 0.01X E. 0.001X F. 0.0001X G. This is impossible to calculate without more information.
A.. 10,000X
In which way are archaea and eukaryotes the same? A. Have a cell wall for rigidity B. Can use flagella for movement C. Contain mitochondria for energy production D. Contain membrane-bound organelles
B. Can use a flagella for movement
43. All of the following are diameters of cells that would be resolved in a microscope with a limit of resolution of 0.2 µm except ______. A. 0.2 mm B. 0.1 µm C. 2.0 µm D. 0.2 µm
B. 0.1 µm
In general, eukaryotic cells are about _____ times larger than bacterial or archaeal cells. A. 2 B. 10 C. 50 D. 1000
B. 10
Bacterial endospores are produced by ______. A. Entamoeba B. Bacillus C. Mycoplasma D. Staphylococcus
B. Bacillus
After returning from a trip to Africa, Tom feels tired and weak and has severe anemia. A blood smear reveals a protozoan in his blood and the health care provider diagnoses malaria. Which of the following could be the causative agent of this disease? A. Plasmodium vivax B. Giardia lamblia C. Trichophyton rubrum D. Taenia solium E. HIV
B. Giardia lamblia
Which of the following represents a virus family name? A. Herpes simplex virus B. Herpesviridae C. Picornavirus D. Enterovirus E. Hepatitis B virus
B. Herpesviridae
Larval development of helminths occurs in which host? A. Primary host B. Intermediate host C. Definitive host D. Transport host E. Larval development takes place in all hosts.
B. Intermediate host
43. A bacterial genus that has waxy mycolic acid in the cell walls is ______. A. Bacillus B. Mycobacterium C. Mycoplasma D. Corynebacterium. E. Streptococcus
B. Mycobacterium
You have made a smear of a bacterial culture and have performed the Gram stain on it. Looking at the organism under the microscope, you notice that the cells do not seem to be the dark blue-purple of a gram-positive reaction, but instead are light purple. Your staining procedure was performed correctly. What is your best explanation as to why the bacteria have stained this way? A. The bacteria were taken from an inappropriate medium, and a chemical is interfering with proper staining of the cells. B. There is something in the wall of the bacteria that has affected the uptake of the crystal violet into the cell wall, thereby staining it improperly. C. The specimen did not undergo heat fixation before staining; therefore, the primary dye does not stick properly to the wall. D. These are mutant bacteria which cannot be stained like other bacteria.
B. There is something in the wall of the bacteria that has affected the uptake of the crystal violet into the cell wall, thereby staining it improperly.
Which of the following is not a viral order in the classification system? A. Caudovirales B. Vaccinia virus C. Nidovirales D. Mononegavirales
B. Vaccinia virus
sterile refers to _____________. A. homogenized B. absence of any life forms and viral particles C. pathogen-free D. pasteurized E. absence of spores
B. absence of any life forms and viral particles
90. The division of microbes termed the Mendosicutes have a cell wall type best described as ______. A. lacking a cell wall B. archaeal C. gram-positive D. gram-negative
B. archaeal
A common method for cultivating viruses in the lab is to use in vitro systems called _____ cultures. A. embryo B. cell C. plaque D. bacteriophage E. egg
B. cell
11. You need to determine if a pure culture of bacteria is gram-positive or gram-negative, but you've just spilled your only solution of crystal violet so you can't do a Gram stain. You decide to try a lysozyme treatment on a sample of each culture and then examine the samples under the microscope. The expected result is: A. gram-positives will lyse and appears as debris; gram-negatives will lyse but more slowly. B. gram-positives will lyse and appears as debris; gram-negatives will be unaffected. C. gram-positives will lyse and appears as debris; gram-negatives will lose cellular morphology and appear as cocci. D. gram-negatives will lyse and appears as debris; gram-positives will lose cellular morphology and appear as cocci. E. gram-negatives will lyse and appears as debris; gram-positives will be unaffected.
B. gram-positives will lyse and appears as debris; gram-negatives will be unaffected.
astrobiology is consider a sub-discipline of microbiology because: A. life elsewhere in the universe is likely to be microbial. B. microbes are known to exist on other planets. C. all extraterrestrials known are microbial. D. only microbes can reproduce under the extreme conditions in outer space.
B. microbes are known to exist on others planets
Mannitol salt agar is selective for organisms in which bacterial genus? A. Salmonella B. Staphylococcus C. Escherichia D. Neisseria E. Streptococcus
B. staphylococcus
Your microscope has a resolving power of 0.15 um. The specimen that you will be observing is a bacterial cocci the size of 0.1 um in diameter. Which of the following statements is correct? A. The cocci will appear much smaller than their actual size because of the low resolution. B. The cocci will be fuzzy-looking and blend together. C. The cocci will not be visible. D. The cocci will be readily visible and distinct.
B. the cocci will be fuzzy-looking and blend together
Table 3.6 in your textbook uses Paramecium to illustrate several types of light microscopy. Each image is magnified 230X and measures about 4 cm. The actual size of a Paramecium is about______ A. 920 mm B. 0.2 mm C. 175 mm D. 57.5 mm E. 4,000 mm
C. 175 mm
Which type of microscope shows cells against a white background? A. Confocal B. Electron C. Bright-field D. Fluorescence E. Phase-contrast
C. Bright-field
Which of the following is not an inoculating tool? A. Pipette B. Swab C. Petri dish D. Loop E. Needle
C. Petri dish
Organisms called parasites are __________ A. the decomposers in ecosystems B. always viruses C. always harmful to their host D. free-living
C. always harmful to their host
A microbiologist must culture a patient's feces for intestinal pathogens. Which is likely to be present in a selective medium for this purpose? A. Thioglycolic acid B. Sheep red blood cells C. Bile salts D. Peptone E. NaCl
C. bile salts
53. The outcome of the Gram stain is based on differences in the ______. A. cell membrane B. flagella C. cell wall D. ribosomes
C. cell wall
Peptidoglycan is a unique macromolecule found in bacterial ______. A. slime layers B. capsules C. cell walls D. cell membranes
C. cell walls
When a eukaryotic cell is not undergoing mitosis, the DNA and its associated proteins appear as a visible, thread-like mass called ______. A. nucleoplasm B. the nuclear envelope C. chromatin D. the nucleolus E. the nucleosome
C. chromatin
Which type of microscope cannot image live specimens? A. Differential interference B. Bright-field C. Electron D. Dark-field E. Phase-contrast
C. electron
Lipopolysaccharide is an important cell envelope component of ______.: A. acid-fast bacteria B. gram-positive bacteria C. gram-negative bacteria D. mycoplasmas E. protoplasts
C. gram-negative bacteria
All of the following pertain to the fluorescence microscope except: A. it is a type of compound microscope. B. it is used to diagnose certain infections. C. it uses electrons to produce a specimen image. D. it requires the use of dyes like acridine or fluorescein. E. it requires an ultraviolet radiation source.
C. it uses electrons to produce a specimen image
10. Which of the following pairs is mismatched? A. Protozoa; unicellular B. Algae; multicellular C. Fungi; multicellular D. Protozoa; multicellular E. Helminths; multicellular F. Fungi; unicellular
C. protozoa: multicellular
Which of the following is not a phenotypic trait of bacteria? A. Cell shape B. Biochemical reactions C. rRNA sequence D. Nutrient requirements
C. rRNA sequence
The number one worldwide infectious diseases are ___________ A. AIDS-related diseases B. malaria and other protozoan diseases C. respiratory diseases D. measles and other rash diseases E. diarrheal diseases
C. respiratory diseases
At present, the most accurate indicator of evolutionary relatedness among organisms is the: A. size of the bacterial chromosome. B. similarities of cell membrane proteins. C. sequence of the ribosomal small subunit RNA. D. size of the ribosomes. E. size of the periplasmic space.
C. sequence of the ribosomal small subunit RNA
The endosymbiotic theory says that precursor eukaryotic cells acquired cilia by endosymbiosis with a(n) _____ ancestor and others gained photosynthetic ability from endosymbiosis with a(n) _____ ancestor. A. archaeal, cyanobacterial B. protozoan, algal C. spiral, cyanobacterial D. helminth, algal
C. spiral, cyanobacterial
8. Biologists have found evidence that eukaryotic cells evolved from prokaryotic organisms by a process of intracellular ______. A. commensalism B. parasitism C. symbiosis D. mutualism
C. symbiosis
38. What type of phage enters an inactive prophage stage? A. Primary B. Secondary C. Temperate D. Temporary E. Transformed
C. temperate
You apply the acid-fast stain method to a patient's specimen, an aspirate from the lungs. Microscopic examination reveals a large number of bright pink-red bacillus-shaped bacteria in the smear. Which statement is true? A. This is the expected outcome for normal sputum. B. The patient has pneumonia. C. The patient has tuberculosis. D. The patient has an HIV infection.
C. the patient has tuberculosis
A protozoan having a flagellum would be classified in the genus ______. A. Entamoeba B. Toxoplasma C. Trypanosoma D. Enterobius E. Plasmodium
C. trypanosoma
Which of the following statements is correct? A. All saprobes are heterotrophic, but only some are parasitic. B. All heterotrophs are fungi, and include both parasites and saprobes. C. All heterotrophs are parasites, but only some are saprobes. D. All fungi, whether parasite or saprobe, are heterotrophs.
D. All fungi, whether parasite or saprobe, are heterotrophs
86. Sterilizing filters have a pore size of 0.22 μm. Which of the following statements is true? A. Bacterial cells are typically between 1,000-10,000 nm and pass through the filter, whereas most viruses are between 20 and 200 nm and are therefore blocked. B. Bacterial cells are typically between 1-10 um and pass through the filter, whereas most viruses are between 20 and 200 nm and are therefore blocked. C. Bacterial cells are typically between 1-10 m and are blocked by the filter, whereas most viruses are between 20 and 200 nm and therefore pass through. D. Bacterial cells are typically between 1-10 nm and are blocked by the filter, whereas most viruses are between 20 and 200 m and therefore pass through.
D. Bacterial cells are typically between 1-10 nm and are blocked by the filter, whereas most viruses are between 20 and 200 m and therefore pass through.
75. The term that refers to flagella at both poles of the cell is ______. A. peritrichous B. atrichous C. monotrichous D. amphitrichous E. lophotrichous
D. amphitrichous
75. The bacterial flagellum has three components. In order from the cytoplasm to the external environment, they are A. hook, basal body, and filament B. filament, hook, and basal body C. filament, basal body, and hook D. basal body, hook, and filament E. basal body, filament, and hook
D. basal body, hook, filament
A common medium for culturing fastidious bacteria is _______ A. trypticase soy agar B. reducing medium C. mannitol salt agar D. blood agar E. MacConkey medium
D. blood agar
Chitin is a chemical component of the cell walls of ______. A. helminths B. protozoa C. algae D. fungi E. bacteria
D. fungi
You are observing an organism under the microscope and you note that it has a cell wall, no chloroplasts, and a nucleus. Your prediction would be that this organism is a(n) ______. A. alga B. protozoan C. bacterium D. fungus E. virus
D. fungus
The activation of a prophage is called ______. A. activation B. lysogeny C. transformation D. induction E. adsorption
D. induction
Viruses acquire envelopes around their nucleocapsids during ______. A. replication B. assembly C. adsorption D. release E. penetration
D. release
Which term refers to the microscope's ability to show two separate objects as discrete and distinct? A. Contrast B. Magnification C. Refraction D. Resolution
D. resolution
A scanning confocal microscope A. produces specimen images on electron micrographs. B. uses dyes that emit visible light when excited by ultraviolet radiation. C. uses ultraviolet light to form a specimen image. D. scans narrow planes and can build a three-dimensional image of the specimen.
D. scans narrow planes and can build a three-dimensional image of the specimen
a microbiologist inoculates Staphylococcus aureus into a culture medium. Following incubation, both Staphylococcus aureus and Staphylococcus epidermidis are determined to be growing in this culture. What is the most likely explanation? A. The microbiologist used too much inoculum. B. The culture medium was selective. C. The culture medium was differential. D. The culture was contaminated. E. The incubation temperature was incorrect.
D. the culture was contaminated
Which of the following occurs during assembly? A. The nucleocapsid is formed. B. New viral nucleic acid is formed. C. Viral spikes insert in host cell membrane. D. The nucleocapsid is formed and viral spikes insert in host cell membrane. E. The viral envelope and the host cell membrane fuse.
D. the nucleocapsid is formed and viral spikes insert in host cell membrane
Viral tissue specificities are called ______. A. ranges B. virions C. receptacles D. tropisms E. uncoating
D. tropisms
eukaryotic cells are larger than bacterial or archaeal cells; all cells are larger than macromolecules. where do viruses fit on this scale? A. Viruses are smaller than eukaryotic cells, but larger than bacterial or archaeal cells. B. Viruses are smaller than macromolecules. C. Viruses are larger than eukaryotic cells. D. Viruses are smaller than bacterial or archaeal cells, but larger than macromolecules.
D. viruses are smaller than bacterial or archaeal cells, but larger than macromolecules
Bacterial cultures are easily identified from their microscopic appearance. T or F.
F
34. Boiling water (100°C) can normally destroy endospores. True or False
False
Bacteriophages do not undergo adsorption to specific host cell receptors prior to penetration. True False
False
The nuclear envelope is a single lipid layer. True or false
False
Viruses are not filterable. True False
False
A fully formed virus that can cause an infection in a host cell is called a virion. True False
True
A medium that is gel-like has less agar in it compared to a solid medium. T or F
True