Microbiology final exam

The type of microscope in which you would see brightly illuminated specimens against a black background is A) bright-field. B) dark-field. C) phase-contrast. D) fluorescence. E) electron.

B. Dark-field

A student unearths a cell that was housed in a 250-million-year-old salt crystal, it's more than likely a(n) A) protein. B) endospore. C) capsule. D) archaea.

B. Endospore

All of the following are correct about a slime layer, except A) it is a type of glycocalyx. B) it can be easily washed off the cell. C) it protects the cell from loss of water and nutrients. D) it enables movement of cells. E) it allows cells to participate in biofilms.

D. It enables movement of cells

Helminths are A) bacteria. B) protozoa. C) molds. D) parasitic worms. E) infectious particles.

D. Parasitic worms

Which of the following terms refers to microorganisms that live in or on the body and cause harm? A) Mesophiles B) Thermophiles C) Commensals D) Pathogens E) Halophiles

D. Pathogens

Mannitol salt agar is selective for which bacterial genus? A) Salmonella B) Streptococcus C) Neisseria D) Staphylococcus E) Escherichia

D. Staphylococcus

A microbiologist inoculates Staphylococcus epidermidis and Escherichia coli into a culture medium. Following incubation, only the E. coli grows in the culture. What is the most likely explanation? A) The microbiologist used too much inoculum. B) The culture is contaminated. C) The incubation temperature was incorrect. D) The culture medium must be selective. E) The culture medium must be differential.

D. The culture medium must be selective

Which of the following is a unique characteristic of viruses that distinguishes them from the other major groups of microorganisms? A) Viruses cause human disease. B) Viruses are composed of cells that lack nuclei. C) Viruses cannot be seen without an electron microscope. D) Viruses contain genetic material. E) Viruses lack ribosomes.

E. Viruses lack ribosomes

The viral _____ is responsible for introducing the viral DNA or RNA into the cell. A) capsid B) DNA C) envelope D) bacteria E) both capsid and envelope

E. Both capsid and envelope

Which microscope achieves the greatest resolution and highest magnification? A) Bright-field B) Dark-field C) Phase-contrast D) Fluorescence E) Electron

E. Electron

Spontaneous generation is the idea that A) germs cause infectious diseases. B) microbes are diverse and ubiquitous. C) microbes placed in an infusion can grow in it. D) aseptic techniques reduce microbes in medical settings. E) living things arise from nonliving matter.

E. Living things arise from no living matter

An organism that cannot tolerate any oxygen gas in its environment is a/an A) aerobe. B) obligate aerobe. C) facultative anaerobe. D) microaerophile. E) obligate anaerobe.

E. Obligate anaerobe

An amino acid contains all of the following except A) an amino group. B) a carboxyl group. C) a variable R group. D) a carbon atom. E) a nitrogenous base.

E. a nitrogenous base

All of the following are poly saccharides, except A) dextran in some bacterial slime layers. B) agar used to make solid culture media. C) a cell's glycocalyx. D) cellulose in certain cell walls. E) prostaglandins in inflammation.

E. Prostaglandins I'm inflammation

Which of the following spores are sexually produced? A) Chlamydospores B) Sporangiospores C) Blastospores D) Arthrospores E) Zygospores

E. zygospores

The movement of substances from higher to lower concentration across a semipermeable membrane that must have a specific protein carrier but no energy expenditure is called A) facilitated diffusion. B) diffusion. C) active transport. D) osmosis. E) endocytosis.

A. Facilitated diffusion

Indicate which of the following are participants in Type 2 hypersensitivity reactions. Check all that apply. A) IgG and IgM antibodies B) IgE antibodies C) complement proteins D) Cells expressing foreign antigens or autoantigens. E) bacterial cells F) T C cells G) NK cells

A. IgG and IgM antibodies C. Complement proteins D. Cells expressing foreign antigens or autoantigens

When it is important to count the number of cells, determine cell size and differentiate between dead and live cells a/an __________ is used. A) Coulter counter B) flow cytometer C) SEM D) methylene dye indicator E) plate count

B. Flow cytometer

Which is not a characteristic of fungi? A) Fungal cells have cell walls. B) Fungi are photosynthetic. C) Fungi include single-celled and filamentous forms. D) Fungi are heterotrophs. E) Fungi can use a wide variety of nutrients.

B. Fungi are photosynthetic

An allergic reaction is commonly mistaken for an infection because they both have the ability to cause tissue damage, triggering an inflammatory response.

True

Anaerobes can be cultured in a CO2 rich environment, as long as O2 gas is excluded.

True

Azoles are broad-spectrum antifungal agents with a complex ringed structure.

True

Certain complement components stimulate inflammation and phagocytosis.

True

DNA polymerase can only add new nucleotides to the old 3' DNA end.

True

Endotoxin is an exogenous pyrogen.

True

Filtration is an effective method to remove microbes from air and liquids.

True

Genetic differences among species, and within a species, can convey genetic immunity to certain diseases.

True

Hay fever is a generic term for allergic rhinitis due to inhaled plant pollen or molds.

True

Individuals have the ability to possess genetic resistance to certain infections.

True

One of the chief functions of inflammation is to destroy and block microbes from further invasion.

True

Restriction endonucleases are obtained from various species of bacteria.

True

Streptococci and Gonococci are both bacteria that release pus to attract neutrophils.

True

The Kirby-Bauer test uses an agar surface, seeded with the test bacterium, to which small discs containing a specific concentration of several drugs are placed on the surface.

True

The direct cell count, using a flow cytometer, can determine both viable cell numbers and number of dead cells in the sample.

True

Which of the following is found in eukaryotic cells but not in prokaryotic cells? A) Nucleus B) Mitochondria C) Endoplasmic reticulum D) Lysosomes E) All of the choices are correct.

E. All of the choices are correct.

3. Endospores of certain bacterial species can enter tissues in the human body, germinate, and cause an infectious disease.

True

4. Icosahedral viruses have the variation of containing an outside envelope.

True

Which type of medium is able to distinguish different species or types of microorganisms based on an observable change in the colonies or in the medium? A) Differential B) Selective C) Enumeration D) Enriched E) Reducing

A. Differential

An organism that can use gaseous oxygen in metabolism and has the enzymes to process toxic oxygen products is a/an A) aerobe. B) obligate aerobe. C) facultative anaerobe. D) microaerophile. E) obligate anaerobe.

A. Aerobe

Which microscope is the most widely used to show stained cells against a bright background? A) Bright-field B) Dark-field C) Phase-contrast D) Fluorescence E) Electron

A. Bright field

Bacteria with small bunches of flagella emerging from the same site are said to be A) lophotrichous. B) peritrichous. C) monotrichous. D) amphitrichous. E) spirilla.

A. Lophotrichous

Which of the following is correct about viruses? A) Most viruses cannot be seen with a light microscope. B) Viruses are prokaryotic. C) Viruses contain 70S ribosomes. D) Viruses undergo binary fission. E) Viruses contain positive strand RNA.

A. Most viruses cannot be seen with a light

The eukaryotic cell's glycocalyx is A) mostly polysaccharide. B) the site where many metabolic reactions occur. C) also called the cell wall. D) composed of many diverse proteins. E) a layer inside the plasma membrane.

A. Mostly polysaccharide

In general, most DNA viruses multiply in the host cell's _____, while most RNA viruses multiply in the host cell's _____. A) nucleus; cytoplasm B) cytoplasm; cell membrane C) cell membrane; cytoplasm D) cytoplasm; nucleus E) nucleus; endoplasmic reticulum

A. Nucleus; cytoplasm

A pure culture contains only A) one species of microorganism. B) bacteria. C) a variety of microbes from one source. D) All of the choices are correct.

A. One species of microorganisms

All of the following could find a location in or on body tissues suitable for growth except A) psychrophiles. B) anaerobes. C) facultative anaerobes. D) mesophiles. E) capnophiles.

A. Psychrophiles

Organisms that feed on dead organisms for nutrients are called A) saprobes. B) parasites. C) autotrophs. D) lithoautotrophs. E) phototrophs.

A. Saprobes

Which elements are found in all carbohydrates, lipids, proteins, and nucleic acids? A) nitrogen B) carbon C) hydrogen D) oxygen E) phosphorus F) sulfur

B. Carbon C. Hydrogen D. Oxygen

A mold is observed to have asexual conidia, sexual spores within a sac, and septate hyphae. It is most likely classified in the A) Zygomycota. B) Ascomycota. C) Basidiomycota. D) Deuteromycota. E) Fungi Imperfecti.

B. Ascomycota

A bacterial cell that exhibits a single group of flagella is called A) monotrichous. B) lophotrichous. C) peritrichous. D) amphitrichous.

B. Lophotrichous

The term heterotroph refers to an organism that A) uses CO 2 for its carbon source. B) must obtain organic compounds for its carbon needs. C) gets energy from sunlight. D) gets energy by oxidizing inorganic compounds. E) does not need a carbon source.

B. Must obtain organic compounds for its carbon needs

Which of the following magnifies the specimen to produce the real image of the specimen? A) Condenser B) Objective lens C) Ocular lens D) Body E) Nosepiece

B. Objective lens

You identify a new microbial species in an acid pool. In the laboratory, you cannot culture the organism in your pH 7 media. You correctly classify the species as a/an A) facultative acidophile. B) obligate acidophile. C) facultative alkalinophile. D) obligate alkalinophile.

B. Obligate acidophile

An organism that uses CO 2 for its carbon needs and sunlight for its energy needs is called a/an A) heterotroph. B) photoautotroph. C) chemoheterotroph. D) saprobe. E) halotroph.

B. Photoautotroph

Which of the following is the cause of malaria? A) Toxoplasmagondii B) Plasmodium C) Giardia D) Leishmania E) Trypanosoma

B. Plasmodium

The wavelength of light used plus the numerical aperture governs A) illumination. B) resolution. C) magnification. D) size of the field. E) All of the choices are correct.

B. Resolution

The type of chemical bond linking amino acids together is a(n) A) glycosidic bond. B) peptide bond. C) ester bond. D) ionic bond. E) hydrogen bond.

B. a peptide bond

In __________ conditions, the cell wall will help prevent the cell from bursting. A) hypertonic B) hypotonic C) isotonic D) mesotonic E) All of the choices are correct.

B. hypotonic

A microorganism that does not have catalase or superoxide dismutase would find it difficult to live in an environment with A) carbon dioxide. B) oxygen. C) high salt. D) temperatures above 37°C. E) high acidity.

B. oxygen

All of the following are lipids except A) cholesterol. B) starch. C) phospholipid. D) wax. E) triglyceride.

B. starch

DNA polymerase III A) is needed for adding nucleotides during mRNA synthesis. B) synthesizes new DNA only in the 5' to 3' direction. C) cannot add nucleotides to the lagging strand. D) synthesizes an RNA primer. E) All of the choices are correct.

B. synthesizes new DNA only in the 5' to 3' direction.

What type of media is used to demonstrate oxygen requirements of microbes? A) Blood agar B) Thioglycollate C) Sulfite polymyxin sulfadiazine D) Sodium chloride

B. thioglycollate

When a virus is noninfectious it is termed __________. A) alive B) active C) dead D) inactive

D. Inactive

Pasteur used swan-neck flasks in his experiments to prove that A) air had "vital forces" capable of spontaneous generation. B) microbial fermentation could be used to make wine. C) dust in air was a source of living microorganisms. D) microorganisms could cause disease. E) microorganisms could be grown in laboratory infusions.

C) dust in air was a source of living microorganisms

The nurse in an emergency department is reviewing discharge instructions with a client. The client asks for clarification of a zoonosis, in regards to the type of illness. What is the best response by the nurse? A) A zoonosis refers to any viral disease. B) A zoonosis is any disease which can be successfully treated with antibiotics. C) A zoonosis is a disease typically found in animals, but which infects humans. D) A zoonosis is a disease caused by a eukaryotic parasite.

C. A zoonosis is a disease typically found in animals

Which activity is an example of biotechnology? A) Bacteria in the soil secrete an antibiotic to kill competitors. B) A microbiologist uses a microscope to study bacteria. C) Humans use yeast to make beer and wine. D) Mycobacterium tuberculosis causes tuberculosis in the lungs. E) Public health officials monitor diseases in a community.

C. Humans use yeast to make beer and wine.

The Six "I's" of studying microorganisms include all of the following except A) inoculation. B) incubation. C) infection. D) isolation. E) identification.

C. Infection

Which of the following is found in DNA but not in RNA? A) ribose B) adenine C) thymine D) uracil E) nucleotides

C. Thymine

Cultures of a bacterial species were incubated out on the incubator shelf, in an anaerobic jar, and in a candle jar. After incubation there was moderate growth of cultures in the candle and anaerobic jars, but heavy growth of the culture on the incubator shelf. This species is a/an A) aerobe. B) anaerobe. C) facultative anaerobe. D) microaerophile. E) capnophile.

C. facultative anaerobe.

A student forgot to label a beaker containing a DNA solution and a beaker containing a glucose solution. If chemical analysis was performed to identify the contents of each beaker, which of the following would be found in the beaker of DNA but not in the beaker with glucose? A) amino acids B) hydrogen and oxygen atoms C) nitrogen and phosphorus D) fatty acids E) carbon atoms

C. nitrogen and phosphorus

An organism that grows slowly in the cold but has an optimum growth temperature of 32°C is called A) an extremophile. B) a thermophile. C) a psychrophile. D) a facultative psychrophile. E) thermoduric.

D. A facultative psychrophile.

One nucleotide contains A) one phosphate. B) one pentose. C) one nitrogen base. D) All of these choices are correct.

D. All of these choices are correct

The enzyme that helps pack DNA into the cell by coiling the DNA into a tight bundle is A) DNA ligase. B) DNA polymerase. C) DNA helicase. D) DNA gyrase. E) primase.

D. DNA gyrase

Which of the following branches of Microbiology is utilized in diagnosing or treating someone who has broken out in hives and is experiencing respiratory distress due to an exposure to a microbial toxin? A) Agricultural Microbiology B) Epidemiology C) Biotechnology D) Immunology E) Industrial Microbiology

D. Immunology

Select the FALSE statement about viruses. A) Cellular life-forms most likely preceded the origin of viruses since viruses need host cells in which to develop and reproduce. B) Viruses are the most numerous microbes on Earth. C) Viruses have impacted the evolution of all other cellular life-forms including bacteria, Achaeans, and eukaryotes. D) When viruses are treated in a way that prevents them from entering host cells and reproducing, they are said to be dead.

D. When viruses are treated in a ways that prevents them from entering host cells and reproducing, they are said to be dead

Which term describes human pathogens? A) Psychrophiles B) Thermophiles C) Halophiles D) Mesophiles E) Acidophiles

D. mesophiles.

Cultures of a bacterial species were incubated on the shelf of a refrigerator, out on a lab bench top, on the shelf of a 37°C incubator, and on the shelf of a 50°C incubator. After incubation, there was no growth at 37°C and 50°C, slight growth out on the bench top, and abundant growth at refrigeration. What term could be used for this species? A) Halophile B) Mesophile C) Anaerobe D) Psychrophile E) Capnophile

D. psychrophile

A microaerophile A) grows best in an anaerobic jar. B) grows with or without oxygen. C) needs normal atmospheric levels of oxygen. D) requires a small amount of oxygen but won't grow at normal atmospheric levels.

D. requires a small amount of oxygen but won't grow at normal atmospheric levels.

5. A mega virus is smaller than 22 nm.

False

6. Viruses are considered living organisms.

False

An example of gene therapy is the insertion of the gene for human growth hormone into E. coli cells.

False

As a part of the innate immune system, natural passive immunity results in long-term protection against microbial pathogens.

False

B-lymphocytes and T-lymphocytes mature in the thymus gland.

False

DNA replication initiation occurs in multiple origins of replication around the bacterial chromosome.

False

Eczema is an autoimmune disorder.

False

Epidemiology is only concerned with study of the frequency and distribution of infectious diseases.

False

Introns have no detectable functions.

False

Isopropyl alcohol wiped across a skin site can sterilize it.

False

MHC II markers are found on "self" cells that are not involved in immune function.

False

Obligate saprobes can adapt to a living host.

False

Only inanimate objects can be effectively decontaminated.

False

Physical methods of microbial control will typically sterilize, whereas chemical methods will only disinfect.

False

Systemic lupus is considered a Type II immunopathology.

False

The adaptive immune response includes immune cells' memories of past pathogens. In the future, those immune cells will be better able to respond to a multitude of different pathogens because their "memory" is highly mutagenic.

False

The kinds of microbes potentially present on a surface are not an important factor in choosing which chemical agent is required for sterilization.

False

The majority of microbes live and grow in habitats between pH 7 and 9.

False

Whether an organism is an autotroph or heterotroph depends on its source of nitrogen.

False

1. Bacteria in the genus Mycoplasma and bacteria called L-forms lack cell walls.

True

2. The prokaryotic cell membrane is a site for many enzymes and metabolic reactions.

True