Microbiology Exam 1 - Ch. 1, 3, 4, 10, 12

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Late log phase of the bacterial growth curve A. is marked by the production of primary metabolites. B. is marked by the production of secondary metabolites. C. is a transition into the death phase. D. shows a decline in cell numbers.

B. is marked by the production of secondary metabolites.

In a rapidly multiplying bacterial population, cell numbers increase A. arithmetically. B. logarithmically. C. linearly. D. indirectly.

B. logarithmically.

Carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur may be considered A. minor elements. B. major elements. C. neutral elements. D. acidic elements.

B. major elements.

Algae are important environmentally as A. major producers of carbon dioxide. B. major producers of oxygen. C. local flora. D. local contaminants.

B. major producers of oxygen.

Organisms A. may be classified in four domains. B. may be classified in three domains. C. probably do not have a common ancestor. D. have never shared genes between domains. E. may be classified in three domains, probably do not have a common ancestor, AND have never shared genes between domains.

B. may be classified in three domains.

Lice and mites A. are both arachnids. B. may both be spread by personal contact. C. are intestinal parasites. D. cause Lyme disease.

B. may both be spread by personal contact.

The terms yeast, mold, and mushrooms refers to fungal A. reproduction. B. morphology. C. nutrition. D. parasites.

B. morphology.

A tangle of fungal hyphae is generally known as a A. bud. B. mycelium. C. germ tube. D. spore.

B. mycelium.

Organisms that require gaseous oxygen for metabolism are referred to as A. facultative aerobes. B. obligate aerobes. C. facultative anaerobes. D. microaerophiles.

B. obligate aerobes.

Both viruses and viroids are A. capable of independent reproduction. B. obligate intracellular parasites. C. interdependent with one another for reproduction. D. larger than most bacteria in size.

B. obligate intracellular parasites.

The optimum pH for growth of most species of bacteria is A. pH 5. B. pH 7. C. pH 9. D. pH 6.

B. pH 7.

Candle jars are usually used to A. store candles. B. provide an atmosphere with CO2. C. stimulate the growth of obligate anaerobes. D. prevent the growth of obligate aerobes. E. provide an atmosphere with CO2 AND stimulate the growth of obligate anaerobes.

B. provide an atmosphere with CO2.

All the bacterial cells that result from the replication of a single original bacterial organism are said to be a A. population. B. pure culture. C. lag culture. D. mutant culture.

B. pure culture.

Deuteromycetes has been further classified using A. DNA probes. B. rRNA analysis. C. Southern blotting. D. replica plating.

B. rRNA analysis.

Peptone A. refers to a hydrolysate of carbohydrates used in growth media. B. refers to a hydrolysate of proteins used in growth media. C. consists of a water extract of beef. D. consists of a mix of monosaccharides and oligosaccharides. E. refers to a hydrolysate of proteins used in growth media AND consists of a water extract of beef.

B. refers to a hydrolysate of proteins used in growth media.

Bacteria are good models to use because they A. are large in size. B. share many biochemical/physiological properties with more complicated organisms. C. can be assembled into multicellular organisms. D. have complicated growth requirements.

B. share many biochemical/physiological properties with more complicated organisms.

When cellular slime molds run out of food, they form a A. plasmodium. B. slug. C. myxamoeba. D. rhizoid.

B. slug.

In higher organisms, successful mating can occur between members of the same A. genus. B. species. C. class. D. order.

B. species.

The simplest technique for isolating bacteria in growth media is referred to as the A. pour-plate method. B. streak-plate method. C. serial dilution method. D. MPN method.

B. streak-plate method.

The more closely related two organisms are, A. the less they look alike. B. the more similar the nucleic acid sequence. C. the less similar the nucleic acid sequence. D. the more they are phenotypically similar. E. the more similar the nucleic acid sequence AND the more they are phenotypically similar.

B. the more similar the nucleic acid sequence.

Bioremediation refers to A. rehabilitating wayward bacteria. B. using bacteria to clean up pollutants. C. vaccine development. D. monitoring newly discovered disease organisms.

B. using bacteria to clean up pollutants.

The scientist usually considered the first to see microorganisms, which he called "animalcules", was A. Redi. B. van Leeuwenhoek. C. Pasteur. D. Tyndall.

B. van Leeuwenhoek

The word "animalcule" was coined by A. Pasteur. B. van Leeuwenhoek. C. Redi. D. Tyndall.

B. van Leeuwenhoek.

The work of Tyndall and Cohn A. supported the idea of spontaneous generation. B. was used to explain why others investigating spontaneous generation had obtained results that were opposite of those obtained by Pasteur. C. showed that microbes caused disease. D. allowed scientists to see microorganisms.

B. was used to explain why others investigating spontaneous generation had obtained results that were opposite of those obtained by Pasteur.

Fungi capable of dimorphism grow either as A. rhizoids or hyphae. B. yeast-like or mycelium. C. germ tubes or buds. D. spores or mushrooms.

B. yeast-like or mycelium.

Which of the rRNA molecules has proven the most useful in taxonomy/identification? A. 5S B. 16S C. 23S D. 80S

B. 16S

To study the phylogeny of eukaryotes, A. 16S rRNA is used. B. 18S rRNA is used. C. 40S rRNA is used. D. 80S rRNA is used.

B. 18S rRNA is used.

The pH at which most fungi thrive is A. 3.0. B. 5.0. C. 7.0. D. 8.0.

B. 5.0

A pure culture in exponential growth phase has a bacterial concentration of 6.4 x 108 cells/ml. If the bacterium has a generation time of 1 h, how long ago was the cell concentration 8.0 x 107 cells/ml? A. 1 h B. 2 h C. 3 h D. 4 h

C. 3 h

The reference for taxonomic descriptions of bacteria is A. Gray's Anatomy. B. Websters Manual of Taxonomic Bacteriology. C. Bergey's Manual of Systematic Bacteriology. D. Bacteriology.

C. Bergey's Manual of Systematic Bacteriology.

Which of the following microscope types would be least useful in viewing unstained living cells? A. Phase contrast B. Interference C. Bright-field D. Dark-field

C. Bright-field

Which amino acid(s) is/are found only in the cell walls of bacteria? A. Glycerol B. L-form of glycine C. Diaminopimelic acid D. L-form of methionine E. L-form of glycine AND L-form of methionine

C. Diaminopimelic acid

Phage typing A. is useful for determining eukaryotic cell types. B. is used to extract DNA from cells. C. is used to distinguish bacterial strains. D. is dependent on the type of eukaryotic cell. E. is used to distinguish bacterial strains AND is dependent on the type of eukaryotic cell.

C. is used to distinguish bacterial strains.

When doing experiments with bacteria, A. it is usually not necessary to standardize which stage of growth is used. B. it is best to use colonies as all the bacteria in a colony are at the same stage of growth. C. it is best to use bacteria from the same stage of growth. D. the age of the bacteria is not important.

C. it is best to use bacteria from the same stage of growth.

The prefix photo- indicates that an organism will make use of _______ for energy purposes. A. chemicals B. organics C. light D. inorganics

C. light

Peptidoglycan A. may be digested by penicillin. B. consists of a long string of NAG coupled to a long string of NAM. C. may be digested by lysozyme. D. is found in bacteria, archaea, and plants.

C. may be digested by lysozyme.

A new organism was found that was unicellular and 1 cm long. The "large" size of this organism alone would A. mean that it could not be a bacterium. B. mean that it had to be a protista. C. mean little. D. mean that it had to be in the domain eukarya.

C. mean little.

The lag phase of the bacterial growth curve is marked by A. a decrease in cell mass. B. dormant, metabolically inactive cells. C. metabolically active cells. D. vigorously dividing cells.

C. metabolically active cells.

Although it is said that the twentieth century was the Age of Physics, it is predicted that the twenty-first century will be the age of A. chemistry. B. computers. C. microbial biodiversity. D. mathematics.

C. microbial biodiversity.

Mycobacterium leprae is typically found infecting the ears, toes, and fingers of its host due to its A. requirement for well-oxygenated blood. B. easy access to those parts. C. need for cooler temperatures. D. long incubation period.

C. need for cooler temperatures.

The system by which organisms are named is referred to as A. systematics. B. naming. C. nomenclature. D. cladistics.

C. nomenclature.

The two magnifying lenses found in a light microscope are the A. basic and transverse. B. small and large. C. ocular and objective. D. simple and phase.

C. ocular and objective.

Shake tubes are used to determine the A. pH requirements for bacterial growth. B. temperature requirements for bacterial growth. C. oxygen requirements for bacterial growth. D. salt requirements for bacterial growth.

C. oxygen requirements for bacterial growth.

The macromolecule found in the cell walls of all bacteria is A. lipid A B. teichoic acid. C. peptidoglycan. D. glycocalyx.

C. peptidoglycan.

In 1908 Orla-Jensen suggested that bacteria be grouped according to their A. arrangement. B. morphology. C. physiology. D. Gram stain.

C. physiology.

Within a lab, a scientist has two samples-the first is a prion sample, while the second is a viroid sample. But those pesky labels have come off of the flasks! She wants to run a simple analysis to determine which one is which. What type of molecule would she look for to determine which one is which? A. Lipids B. DNA C. Protein D. Polysaccharides

C. Protein

A soluble greenish pigment is produced by A. Serratia marcescens. B. E. coli. C. Pseudomonas aeruginosa. D. streptococci.

C. Pseudomonas aeruginosa.

Two isolates with identical RFLPs are considered A. the same strain. B. different strains. C. possibly the same strain. D. different genera.

C. possibly the same strain.

In the 1930s Kluyver and van Niel proposed a classification scheme based on A. Gram reactions. B. biochemical relationships. C. presumed evolutionary relationships. D. DNA sequences.

C. presumed evolutionary relationships.

The ability to exist as either a trophozoite or a cyst is characteristic of many A. fungi. B. viruses. C. protozoa. D. bacteria.

C. protozoa.

Bacteria A. are not found on our bodies. B. are only found on small select parts of our bodies. C. provide protection to us from disease by covering our bodies, crowding out "bad" invading bacteria. D. always cause disease when growing on our bodies.

C. provide protection to us from disease by covering our bodies, crowding out "bad" invading bacteria.

The cytoplasmic membrane of both eukaryotes and prokaryotes functions to A. form endoplasmic reticulum. B. produce energy. C. regulate movement of molecules that enter and leave the cell. D. form lysosomes and Golgi apparatus.

C. regulate movement of molecules that enter and leave the cell.

The Gram stain and the endospore stain both use A. crystal violet. B. iodine. C. safranin. D. malachite green. E. acidic dyes.

C. safranin.

A medium that inhibits the growth of organisms other than the one being sought is termed a(n) A. synthetic medium. B. specific culture medium. C. selective medium. D. enrichment medium.

C. selective medium.

An early attempt by Cohn at bacterial classification grouped bacteria according to their A. biochemistry. B. Gram stain. C. shape. D. arrangement.

C. shape.

The site in a photosynthetic eukaryotic cell where photosynthesis occurs is the A. nucleus. B. carotenoid. C. mitochondria. D. chloroplast.

D. chloroplast.

The structures present in the hay infusions used in experiments on spontaneous generation that made them difficult to sterilize are A. chlorophyll. B. toxins. C. organelles. D. endospores.

D. endospores.

A scientist discovers a new species near coral reefs in Australia. On basic microscopic examination and after conducting a few simple experiments, he finds that this single-celled species is photosynthetic (using sunlight for energy), has a rigid cell wall structure with no peptidoglycan, uses a flagellum for motion, and contains a variety of internal structures that are bound by plasma membranes. Given this information, this new species is most likely a ______ cell in the _____ subcategory. A. bacterial; eubacterial B. eukaryotic; fungus C. archaebacterial; fungus D. eukaryotic; algae E. eukaryotic; protozoan

D. eukaryotic; algae

Agar A. is a useful nutrient source for most bacteria. B. is a hydrolysate of proteins. C. stays liquid through the typical range of incubation temperatures. D. has chemical and physical properties that make it almost ideal for solidifying media.

D. has chemical and physical properties that make it almost ideal for solidifying media.

The relatedness of organisms determined by counting common characteristics A. is called evolutionary taxonomy. B. is called amino acid sequences. C. is called DNA sequences. D. is called numerical taxonomy. E. suggests the organisms are very closely related at the species level AND means the GC content is 45%.

D. is called numerical taxonomy.

Which of the following stains is/are considered differential? A. Capsule stain. B. Flagella stain. C. Acid-fast stain. D. Gram stain. E. Acid-fast stain AND Gram stain.

E. Acid-fast stain AND Gram stain.

33. Which group(s) below contain single-celled and multicellular organisms? A. Algae B. Fungi C. Protozoa D. All of the choices are correct. E. Algae AND Fungi

E. Algae AND Fungi

Which is (are) true concerning the cell wall of prokaryotes? A. It determines the shape of the bacteria. B. It prevents the bacteria from bursting. C. It contains peptidoglycan. D. It may be targeted by antimicrobials. E. All of the choices are true.

E. All of the choices are true.

Fatty acid analysis A. can be used to identify Gram-negative bacteria. B. can be used to identify Gram-positive bacteria. C. uses gas chromatography to analyze fatty acid methyl esters. D. requires that cells be grown under standardized conditions. E. All of these choices are correct.

E. All of these choices are correct.

Which may result in Gram-positive bacteria appearing to be Gram-negative? A. Decolorizing too long B. Decolorizing too short C. Using old cultures D. Using young cultures E. Decolorizing too long AND using old cultures

E. Decolorizing too long AND using old cultures

Coccidioidomycosis is A. a fungal disease. B. a protozoal disease. C. caused by Coccidioides sp. D. caused by Candida sp. E. a fungal disease AND caused by Coccidioides sp.

E. a fungal disease AND caused by Coccidioides sp.

Very often clinically relevant information may be obtained by examining A. a wet mount. B. the size and shape of the organism. C. the sequence of proteins. D. the transformation ability. E. a wet mount AND the size and shape of the organism.

E. a wet mount AND the size and shape of the organism.

The human body only contains bacteria during illness. True/False

False

The scientific name of an organism indicates its domain. True/False

False

The size of an organism determines its domain. True/False

False

There are five stages of growth in an open system of culture. True/False

False

Thiomargarita namibiensis could not be a eukaryote because it is only 1 mm in width. True/False

False

Viroids are naked (lacking a protein shell) pieces of DNA that infect plants. True/False

False

Viruses and bacteria are both based on the unit of a cell. True/False

False

Viruses simultaneously contain DNA, RNA, and protein. True/False

False

It is assumed that every colony observed on a streak plate arose from a single bacterium. True/False

True

Mitochondria and chloroplasts are thought to have once been free-living bacteria that invaded another cell. True/False

True

Most of the medically important multicellular parasites are arthropods or helminths. True/False

True

Prokaryotes are the only organisms able to use atmospheric nitrogen as a nitrogen source. True/False

True

Secondary metabolites may be antibiotics. True/False

True

Size and shape may allow one to differentiate between a bacterium, fungus, or protozoan. True/False

True

The three domain systems consist of Archaea, Bacteria, and Eukarya. True/False

True

Typically arthropods serve as vectors of disease, while helminths directly cause disease. True/False

True

Viruses, viroids, and prions are obligate intracellular agents. True/False

True

rRNA sequence comparisons are useful for determining evolutionary relationships. True/False

True

Algae have a vascular system very similar to that found in plants. True/Fase

False

Algae may directly infect humans and cause disease. True/False

False

Archaea are very similar to bacteria and have rigid cell walls made of peptidoglycan. True/False

False

Slime molds and water molds are types of fungi. True/False

False

Smooth endoplasmic reticulum is involved in protein synthesis. True/False

False

Spontaneous generation referred to the idea that organisms came from other organisms. True/False

False

Streptococcus pyogenes can be easily distinguished microscopically from other Streptococcus species. True/False

False

All known species of bacteria are described in Bergey's Manual of Systematic Bacteriology. True/False

True

Based on DNA hybridization, humans and chimpanzees are the same species. True/False

True

Horizontal DNA transfer may make it more difficult to construct phylogenetic trees. True/False

True

Basic dyes A. have negative charges. B. have positive charges. C. are electrically neutral. D. contain both positively and negatively charged particles.

B. have positive charges.

DNA probes have been very useful in A. coding the DNA of organisms grown in vivo. B. identifying organisms in pure culture. C. detecting toxins. D. diagnosing diseases of protozoa.

B. identifying organisms in pure culture.

Viruses may only be grown A. in sterile, cell-free chemical growth media. B. in living cells. C. at body temperature. D. in darkness.

B. in living cells.

The optimal temperature for most human pathogens might be expected to range from A. 35-40C. B. 20-45C. C. 15-25C. D. 93-98.6C.

A. 35-40C.

Your instructor wants you to bring in an example of a biofilm to your lab. Which choice is the best selection for bringing in an intact biofilm for further study? A. Disconnecting and bringing in the old, mildewed showerhead from the showers in your dorm B. Scraping the mold off of the shower curtain in your dorm's bathroom into a paper cup using a butter knife C. Using a toothpick to scrape plaque off of your teeth and smearing it onto a slide to bring in to lab D. Wiping a sponge across a slimy boulder in a stream in a nearby park and bringing it in to lab

A. Disconnecting and bringing in the old, mildewed showerhead from the showers in your dorm

An electron microscope must use electromagnet "lenses" shaped like donuts to direct the electrons onto the specimen. Why? A. Electrons are particles-there are also particles in air. Without a vacuum, the electrons would strike and be scattered by the atoms/particles within the air. B. Because electrons are highly radioactive, and the chamber must be completely sealed to prevent them from escaping and contaminating the lab area. C. This is the method for fixing the specimen to the slide grid for an electron microscope. Without fixing the specimen by vacuum, it would slide off and we wouldn't be able to visualize it. D. All of the above are true.

A. Electrons are particles-there are also particles in air. Without a vacuum, the electrons would strike and be scattered by the atoms/particles within the air.

Paralytic shellfish poisoning occurs when humans eat shellfish that have fed on A. Gonyaulax spp. B. Salmonella spp. C. Vibrio cholerae. D. E. coli.

A. Gonyaulax spp.

You are working in a clinical laboratory in a hospital setting. You're handed a throat swab from a patient. You are told specifically that the physician is only interested in the presence and type of Gram positive cells. Identification isn't the main goal here-just a first step to work towards determining what Gram positive cells might be there.What might you do first to go about working towards this goal? A. Perform a Gram stain. B. Streak the sample for isolation on a tryptic soy agar general purpose medium plate. C. Streak the sample for isolation on a medium that is selective for Gram positive cells while suppressing Gram negative cell growth. D. Grow the microbes on the swab by inoculating a tryptic soy broth liquid medium tube. E. Perform an acid-fast stain.

A. Perform a Gram stain.

A new drug is developed thatinhibits formation of the flagellar filament by impairing production of the protein flagellin. Is this going to be a good drug? A. Potentially-it would definitely only impair bacteria, but wouldn't matter for the ones that don't use a flagellum to move around. B. Potentially-if it could be shown that it also didn't impair the production of the eukaryotic flagellum. C. No-our eukaryotic cells depend on flagella to move around in our body, and this would impair that function. D. No-bacterial flagella are produced using microtubules, not the protein flagellin. This drug would be useless in eliminating bacteria.

A. Potentially-it would definitely only impair bacteria, but wouldn't matter for the ones that don't use a flagellum to move around.

A sample must contain many microorganisms in order to see any using microscopy techniques. Why? A. The area on a microscope slide is very large compared to the relative size of microbes, and you take a very small amount of your sample to place on the slide surface. Therefore, you must have a large number of microbes initially in the culture to increase the chances that you'll come across one or more when looking at the slide surface through the magnifying lenses of the microscope. B. Bacteria are very small, of course. If you don't have a LOT of them, how are you going to see them? C. This is false-microscopy allows us to magnify a specimen to the point where we would be able to visualize even just a few microbes on the surface of the slide. As such, even if there are only a few microbes in a sample, we could easily visualize them with a microscope. D. Microscopes only magnify what's on the slide. If you don't have a lot of microbes on the slide surface, you can't magnify the specimen enough to see them as individual cells.

A. The area on a microscope slide is very large compared to the relative size of microbes, and you take a very small amount of your sample to place on the slide surface. Therefore, you must have a large number of microbes initially in the culture to increase the chances that you'll come across one or more when looking at the slide surface through the magnifying lenses of the microscope.

You are a microbiologist working for a pharmaceutical company and discover a new secreted metabolite that can serve as a medication. Your company asks you to oversee the production of the metabolite. Which of the following is something that is NOT important to consider if you need to grow 5,000 liter cultures of bacteria for the purpose of harvesting the metabolite they secrete? A. The death rate of the bacteria after stationary phase is complete. B. The ideal rate of input of new nutrients into the culture to maintain the cells in log phase. C. The ideal rate of pulling off some of the culture in order to maintain the cells in log phase. D. The best way to mix the large vat in order to keep it homogenous (constant throughout) in terms of nutrients, temperature, and oxygen levels. E. The best way to keep the pH of the entire mixture at the ideal level to promote log phase growth.

A. The death rate of the bacteria after stationary phase is complete.

A research laboratory is investigating environmental factors that would inhibit the growth of Archaea. One question they have is if adding the antibiotic penicillin would be effective in controlling their growth. What do you think the outcome would be if they tried this? A. The penicillin wouldn't affect the Archaea because it prevents crosslinking of peptidoglycan-Archaea don't have this compound in their cell walls. B. The penicillin will inhibit cell wall formation in the Archaea, killing them. C. The penicillin will slow down the growth of the Archaea by damaging the cell wall, but they will still be able to grow somewhat. D. The penicillin will enhance the growth of the Archaea by providing a rich nutrient source.

A. The penicillin wouldn't affect the Archaea because it prevents crosslinking of peptidoglycan-Archaea don't have this compound in their cell walls.

Which is not true of mitochondria and chloroplasts? A. They are found in all organisms. B. They contain DNA and 70S ribosomes. C. They are capable of performing protein synthesis. D. They generate ATP.

A. They are found in all organisms.

Why would all protozoa be expected to require large amounts of water in their habitats? A. They require water to avoid dehydration and death. Without being in water, they would quickly dehydrate (due to their small size) and die. B. They require water to help them during photosynthesis by providing an electron source. C. They require water to move around in to seek food particles. Without water, they would be unable to move at all. D. All of the above are correct.

A. They require water to avoid dehydration and death. Without being in water, they would quickly dehydrate (due to their small size) and die.

Endospores are A. a dormant cell type. B. a form of reproduction. C. an obligate intracellular parasite. D. sensitive to damaging environmental conditions.

A. a dormant cell type.

Most fungi are A. aerobic or facultatively anaerobic. B. obligate anaerobes. C. obligate aerobes. D. microaerophiles.

A. aerobic or facultatively anaerobic.

Organisms that are indifferent to the presence of oxygen and do not use it are A. aerotolerant anaerobes. B. facultative anaerobes. C. obligate aerobes. D. microaerophiles.

A. aerotolerant anaerobes.

A selective growth medium A. allows only certain bacteria to grow. B. allows all bacteria to grow. C. allows no bacteria to grow. D. accentuates differences between the growing bacteria.

A. allows only certain bacteria to grow.

Eukaryotic cells A. are more obviously compartmentalized than prokaryotes. B. usually have a single circular supercoiled piece of DNA. C. contain peptidoglycan in the cell wall. D. have the same size ribosomes as prokaryotes. E. usually have a single circular supercoiled piece of DNA AND contain peptidoglycan in the cell wall.

A. are more obviously compartmentalized than prokaryotes.

Viroids A. are naked (lacking a protein shell) pieces of RNA. B. are naked (lacking a protein shell) pieces of DNA. C. are known to cause neurodegenerative diseases in animals. D. are composed of protein encasing DNA. E. are known to cause neurodegenerative diseases in animals AND are composed of protein encasing DNA.

A. are naked (lacking a protein shell) pieces of RNA.

Viruses A. are obligate intracellular parasites. B. are single-celled organisms. C. consist of only proteins. D. are in the Domain Archaea. E. are obligate intracellular parasites AND are single-celled organisms.

A. are obligate intracellular parasites.

Streptococcus pyogenes would be A. beta hemolytic and catalase negative. B. beta hemolytic and catalase positive. C. alpha hemolytic and catalase negative. D. alpha hemolytic and catalase positive.

A. beta hemolytic and catalase negative.

Facilitated diffusion and active transport A. both transport molecules into or out of a cell. B. are both not very specific as to which molecules are transported. C. both require a concentration gradient to function. D. both require an expenditure of energy in order to transport the molecules. E. both require a concentration gradient to function AND both require an expenditure of energy in order to transport the molecules.

A. both transport molecules into or out of a cell.

The point at which two organisms diverged from a common ancestor A. can be determined by comparing the nucleic acid sequences. B. depends on translational control. C. depends on metabolism. D. is determined on Mac Conkey's media.

A. can be determined by comparing the nucleic acid sequences.

The major criteria used in placing bacteria into different groups is based on differences in A. cell wall structure. B. cell membrane permeability. C. presence or absence of flagella. D. detergent susceptibility.

A. cell wall structure.

Endotoxin A. consists of LPS. B. determines bacterial shape. C. may have different effects depending on the specific bacterial source. D. is toxic due to the effects of the peptide side chains. E. determines bacterial shape, may have different effects depending on the specific bacterial source, AND is toxic due to the effects of the peptide side chains.

A. consists of LPS.

Diatoms are algae whose silicon dioxide-containing shells are useful economically as A. filters. B. fertilizers. C. stabilizers. D. thickeners.

A. filters.

Bacteria have been used to help produce or modify food products A. for several thousand years. B. since the Middle Ages. C. since the late 1800s. D. since the 1950s.

A. for several thousand years.

Diseases such as ulcers and cardiovascular disease A. have been shown to be, or may be due to, a bacterial infection. B. are solely due to lifestyle. C. are solely due to genetics. D. are due to new mutations in bacteria.

A. have been shown to be, or may be due to, a bacterial infection.

Disagreements between conclusions obtained from rDNA data and other techniques may be explained by A. horizontal DNA transfer. B. vertical DNA transfer. C. the difference in translation machinery. D. vertical RNA transfer.

A. horizontal DNA transfer.

If everything else is equal, the best way to observe more details in a microscopic specimen is to A. increase resolution. B. increase magnification.

A. increase resolution.

Viruses are often referred to as A. infectious agents. B. eubacteria. C. archaebacteria. D. cellular agents.

A. infectious agents.

The nucleus A. is a double membrane sac containing DNA and is found in eukaryotes. B. is a single phospholipid membrane sac containing prokaryotic DNA. C. is a smaller structure contained within the eukaryotic nucleolus. D. cannot transport molecules to the cytoplasm due to the double membrane barrier.

A. is a double membrane sac containing DNA and is found in eukaryotes.

The cytoskeleton A. is a dynamic structure composed of microtubules, microfilaments, and intermediate filaments. B. is a static structure that gives a rigid shape to the cell. C. consists of flagella and cilia that are internalized. D. is not necessary for movement or reproduction. E. is a static structure that gives a rigid shape to the cell, consists of flagella and cilia that are internalized, AND is not necessary for movement or reproduction.

A. is a dynamic structure composed of microtubules, microfilaments, and intermediate filaments.

Phagocytosis A. is the ingestion of particles and may be performed by animal cells. B. is the ingestion of particles and may be performed by bacteria. C. is the secretion of proteins. D. is the formation of a lysosome. E. is the ingestion of particles and may be performed by bacteria AND is the formation of a lysosome.

A. is the ingestion of particles and may be performed by animal cells.

Protozoan classification used to be based on their means of A. locomotion. B. growth. C. reproduction. D. obtaining nutrients.

A. locomotion.

Fleas A. may transmit Yersinia pestis. B. may transmit Lyme disease. C. may transmit a toxin. D. have only one host, humans.

A. may transmit Yersinia pestis.

The most necessary habitat requirement of protozoa is A. moisture. B. light. C. temperature. D. UV light.

A. moisture.

Fungal diseases are generally referred to as A. mycoses. B. infections. C. systemics. D. infestations.

A. mycoses.

The ticks of a genetic clock are measured by the A. number of random mutations. B. number of dead cells. C. amount of RNA. D. amount of DNA.

A. number of random mutations.

Algae A. often grow in areas where other forms of life may have difficulty. B. are strictly macroscopic organisms. C. have a vascular system similar to plants. D. are only found in the soil.

A. often grow in areas where other forms of life may have difficulty.

Generally the proteins of thermophiles A. resist denaturation. B. react more efficiently with DNA. C. are easily denatured. D. have a particular amino acid sequence that restricts bond formation. E. are easily denatured AND have a particular amino acid sequence that restricts bond formation.

A. resist denaturation.

The resolving power of a microscope is described as the ability of the microscope to A. separate clearly two objects that are very close together. B. magnify an object. C. separate the colors of an organism's internal structure. D. see structures at various depths in a tissue.

A. separate clearly two objects that are very close together.

A DNA similarity of 75% between two organisms A. suggests the organisms are very closely related at the species level. B. suggests the organisms are not related. C. suggests the organisms may or may not be related. D. means the GC content is 45%.

A. suggests the organisms are very closely related at the species level.

Lyme disease is an example of a disease A. that is due to a greater degree of interaction between humans and tick-carrying animals. B. that is due to a decline in vaccinations. C. that is due to a mutation in the human genome. D. that is due to climate change leading to a greater mosquito population.

A. that is due to a greater degree of interaction between humans and tick-carrying animals.

If while investigating spontaneous generation, Pasteur had his laboratory located in a stable A. the results would, most likely, have supported the idea of spontaneous generation. B. the results would, most likely, have not supported the idea of spontaneous generation. C. this would have had no effect on his results. D. this would have shown his love of horses.

A. the results would, most likely, have supported the idea of spontaneous generation.

HIV/AIDS can be categorized as a new or emerging infectious disease. By putting it into this category, we are effectively saying that A. this infection hasn't been observed in the human population prior to recent (approximately 50 years or sooner) outbreaks. B. this disease has been in susceptible populations for centuries, but has only recently achieved infection levels that became detectable. C. the infectious agent is still evolving and changing, unlike with older, more established diseases such as plague or polio. D. the disease has always been in susceptible populations and causing disease, but we lacked the technology to detect it.

A. this infection hasn't been observed in the human population prior to recent (approximately 50 years or sooner) outbreaks.

Lyme disease is transmitted by A. ticks. B. lice. C. mosquitoes. D. fleas.

A. ticks.

Media that changes color as a result of the biochemical activity of growing bacteria A. usually contain a pH indicator in the media. B. usually contain blood. C. usually require the addition of various reagents before the color is evident. D. is due to a breakdown of a colorless reagent.

A. usually contain a pH indicator in the media.

Nucleic acid techniques have great power as diagnostic tools because they may be A. very specific. B. quick and easy to perform. C. used to enhance the growth of bacteria. D. used to selectively inhibit the growth of certain bacteria.

A. very specific.

The microscope that allows the specimen to appear three-dimensional is the A. phase contrast microscope. B. interference microscope. C. fluorescence microscope. D. dark-field microscope.

B. interference microscope.

You want to examine the structure of the protein coat of a virus by microscopy. Which microscope is your best choice, and why? A. The scanning electron microscope-it has excellent resolution and magnification, much higher than a light microscope, and can clearly visualize viruses. B. An atomic force microscope-this has the highest resolution and magnification of the microscopes we discussed. Here, we want to visualize a subcomponent of the virus particles, so we need the best value for resolution and magnification we can possibly achieve. C. A fluorescent microscope-this will let us tag the protein coat with colored dyes in order to visualize it using this light microscope at 1000x. D. A bright-field light microscope-of course, we'll need to stain the viruses before we can visualize them against the bright white background at 1000x total magnification.

B. An atomic force microscope-this has the highest resolution and magnification of the microscopes we discussed. Here, we want to visualize a subcomponent of the virus particles, so we need the best value for resolution and magnification we can possibly achieve.

Why might it be easier to determine the bacterium that caused pneumonia than one that caused a wound infection? A. There are very few microorganisms that can cause pneumonia, while there are many that can cause wound infections. B. Bacteria that cause pneumonia can be identified with few tests. Many bacteria are normally found on the skin and may be in the wound complicationg indentification of the pathogen. C. We have much better tests for bacteria in the lungs than we do in wounds. D. The techniques of 16S rRNA sequencing are easier to perform on a sample taken from the lungs than a sample taken from a wound.

B. Bacteria that cause pneumonia can be identified with few tests. Many bacteria are normally found on the skin and may be in the wound complicationg indentification of the pathogen.

The group of Fungi in which sexual reproduction has not been observed is A. Ascomycetes. B. Deuteromycetes. C. Zygomycetes. D. Basidiomycetes.

B. Deuteromycetes.

Why were the slime molds and water molds once considered to be fungi? A. Early identification methods focused on appearances rather than biochemical characteristics. B. Early identification methods focused on appearances rather than genetic similarities/differences. C. They ARE fungi. D. They possess the same material in their cell walls (chitin) that fungi possess.

B. Early identification methods focused on appearances rather than genetic similarities/differences.

From most general to most specific, which is the correct order? A. Phylum, class, kingdom, order, family, genus, species B. Kingdom, phylum, class, order, family, genus, species C. Kingdom, phylum, family, class, order, genus, species D. Kingdom, order, family, genus, phylum, class, species

B. Kingdom, phylum, class, order, family, genus, species

How would increased travel lead to increased spread of multicellular eukaryotic parasites? A. Many eukaryotic parasites are transmitted directly from person to person via airborne transmission-so getting an infected individual onto a plane of susceptible individuals would increase spread. B. Many eukaryotic parasites depend on vectors (often small blood-sucking insects) for transmission-so moving an infected individual into an area with new populations of vectors and new susceptible humans would increase the spread of the illness. C. It really would NOT-most individuals are screened for parasitic infections prior to traveling out of highly infected areas. We also have quarantine abilities at customs stations for individuals entering the United States. D. Eukaryotic parasites are too small to travel great distances effectively-by hitching a ride on luggage, clothing, fruit/vegetables, and other food products, they can enter new geographic areas.

B. Many eukaryotic parasites depend on vectors (often small blood-sucking insects) for transmission-so moving an infected individual into an area with new populations of vectors and new susceptible humans would increase the spread of the illness.

A microbiologist obtained two pure isolated biological samples: one of a virus, and one of a viroid. The labels came off during a move from one lab to the next, however. The scientist felt she could distinguish between the two samples by analyzing for the presence of a single type of molecule. What type of molecule would she be looking for to differentiate between the two? A. DNA B. Protein C. Lipids D. RNA

B. Protein

Single-celled eukaryotic organisms that lack chlorophyll are called A. Algae. B. Protozoa. C. Chlorophyta. D. Salmonella.

B. Protozoa.

In a basic staining procedure, which is the correct order? A. Fix, smear, stain B. Smear, fix, stain C. Fix, stain, decolorize D. Smear, decolorize, stain

B. Smear, fix, stain

When DNA probes are used to identify bacterial DNA similarities by hybridization, the probe DNA is heated and the template DNA is treated to separate the two strands.Why would the probe DNA be heated? A. This is the only way to properly label the probe DNA. B. The probe may contain portions that are double-stranded. Heating it up breaks any possible hydrogen bonds that may have formed allowing the single-stranded sequences to hybridize with their complementary targets. C. Heating it up activates the tag on the probe DNA before it hybridizes to the bacterial template DNA. D. DNA hybridization can only take place at high temperatures, so all the DNA must be heated up prior to hybridization.

B. The probe may contain portions that are double-stranded. Heating it up breaks any possible hydrogen bonds that may have formed allowing the single-stranded sequences to hybridize with their complementary targets.

You take absorbance readings on a spectrophotometer across a 6-hour culture of E. coli cells growing in tryptic soy broth (TSB). Your absorbance readings clearly indicate a lag phase, a log phase, and a stationary phase. You come back in and take readings at 8, 10, 12, 14, and 16 hours, but the absorbance number remains the same. Shouldn't it start coming down as the closed batch culture enters death phase? What's the most likely thing that is happening? A. Clearly, something is wrong with the spectrophotometer and it isn't measuring the correct values. Perhaps something is on the detector, making it register falsely high absorbance numbers. B. When we establish a growth curve, we should actually plot the log of the number of viable cells vs. time. However, a spectrophotometer can only measure absorbance. Absorbance is NOT the same as the number of viable cells. Many of the cells in the tube are most likely dead, but the machine can't discriminate between a live cell and a dead one. This keeps the absorbance high even into the death phase. C. It'll happen-E. coli just grow slowly. We haven't gotten to the end of the stationary phase yet. Be patient! D. Perhaps there's a big smudge of something on the tube that is blocking some of the light. This would lead to an elevated reading for every timepoint after the smudge was placed on the tube.

B. When we establish a growth curve, we should actually plot the log of the number of viable cells vs. time. However, a spectrophotometer can only measure absorbance. Absorbance is NOT the same as the number of viable cells. Many of the cells in the tube are most likely dead, but the machine can't discriminate between a live cell and a dead one. This keeps the absorbance high even into the death phase.

Macroscopic algae possess a special structure that acts as an anchor and is commonly called A. a thallus. B. a holdfast. C. roots. D. the stipe.

B. a holdfast.

Agar is obtained from A. bacteria. B. algae. C. protozoans. D. plants.

B. algae.

Sarcoptes scabiei A. transmit bacterial disease. B. are responsible for scabies. C. infect the blood. D. are transmitted by mosquitoes.

B. are responsible for scabies.

In the cultivation of microaerophilic and anaerobic bacteria, A. a(n) candle/anaerobe jar is sufficient. B. atmospheric oxygen in a(n) candle/anaerobe jar is converted to water. C. a packet containing chemicals that generate carbon dioxide and hydrogen is used in a(n) candle/anaerobic jar. D. oxidizing agents are incorporated into the media that react with oxygen.

B. atmospheric oxygen in a(n) candle/anaerobe jar is converted to water.

Protozoans are an important part of the food chain ingesting large numbers of A. fish. B. bacteria and algae. C. shellfish. D. other protozoans.

B. bacteria and algae.

Modern approaches to evolutionary taxonomy often involve A. biochemical differences. B. comparison of DNA and RNA. C. protein similarities. D. lactose fermentation.

B. comparison of DNA and RNA.

Bacteria are present on the body A. only during disease-causing infections. B. constantly. C. only in certain restricted areas. D. never.

B. constantly.

The membranes of eukaryotes and mycoplasma A. contain peptidoglycan. B. contain sterols for "strength." C. contain ergosterol. D. are fixed static structures.

B. contain sterols for "strength."

The cell wall of Gram-positive bacteria A. contains a thin layer of peptidoglycan. B. contains a thick layer of peptidoglycan. C. is, due to its thickness, an excellent barrier to most molecules. D. contains an outer membrane containing LPS. E. contains a thin layer of peptidoglycan AND contains an outer membrane containing LPS.

B. contains a thick layer of peptidoglycan.

The order of reagents in the Gram stain reaction are A. safranin, alcohol, methylene blue, iodine. B. crystal violet, iodine, alcohol, safranin. C. methylene blue, alcohol, safranin. D. crystal violet, alcohol, iodine, safranin.

B. crystal violet, iodine, alcohol, safranin.

In the growth curve of a bacteria population, the bacteria are rapidly increasing in number in the A. lag phase. B. exponential (log) phase. C. stationary phase. D. decline phase. E. boomer phase.

B. exponential (log) phase.

The structures used for motility in both eukaryotes and prokaryotes are A. cilia. B. flagella. C. pili. D. fimbriae.

B. flagella.

Sexual reproduction in algae utilizes meiosis that results in the production of A. spores with twice as much DNA as the parental cells. B. gametes with half the amount of DNA as in the parental cells. C. spores with the same amount of DNA as the parental cells. D. swarming cells with the same amount of DNA as the parental cells.

B. gametes with half the amount of DNA as in the parental cells.

Phylogenetic relationships between prokaryotes are most accurately determined using A. phenotypic characterizations. B. genotypic information. C. the fossil record. D. carbon dating. E. phenotypic characterizations AND genotypic information.

B. genotypic information.

Small organic molecules that must be provided to bacteria in order for them to grow are called A. minerals. B. growth factors. C. water. D. vitamins.

B. growth factors.

Why would it be more difficult to treat diseases in humans caused by members of the Eukarya than diseases caused by the Bacteria? A. Multicellular organisms always have their own immune systems to contend with-so any treatment we develop needs to overcome this built-in protection mechanism in such organisms. B. Since bacteria are so much simpler (being single-celled), they are inherently easier to kill off than multi-cellular eukaryotic microbes. C. Eukaryotic microbes use many of the same enzymes and systems as humans-so we lose the ability to target certain molecules that might be present ONLY in the cell type we want to eliminate. There's too much overlap when both organisms are eukaryotic. D. Eukaryotic microbes (unlike prokaryotes) often secrete compounds that breakdown and eliminate drugs used against them. This makes them much harder to effectively eliminate than bacteria.

C. Eukaryotic microbes use many of the same enzymes and systems as humans-so we lose the ability to target certain molecules that might be present ONLY in the cell type we want to eliminate. There's too much overlap when both organisms are eukaryotic.

During which phase of growth are bacteria most susceptible to antibiotics? A. Lag B. Stationary C. Exponential (log) D. Decline

C. Exponential (log)

Which is not true of the cytoplasmic membrane? A. It defines the boundaries of the cell. B. It is a semipermeable barrier. C. It consists mainly of a fixed, static, phospholipid bilayer. D. It uses proteins as selective gates and sensors. E. All of the choices are true.

C. It consists mainly of a fixed, static, phospholipid bilayer.

Which of the following is/are obligate aerobes? A. Clostridium botulinum B. Escherichia coli C. Micrococcus luteus D. Helicobacter pylori

C. Micrococcus luteus

Are all fungi detrimental (bad) for other organisms? A. Yes-think of molds that destroy plant crops, or fungal infections that cause athlete's foot. All fungi are bad for organisms they colonize. B. Yes-fungi feed directly on organic material (oftentimes killing it or feeding on it after the original organism has died). As such, they are always bad for other organisms. C. No-fungi are sometimes good, sometimes bad for other organisms. It really depends on which fungus you're talking about and the relationship it has with the other organism. Some fungi, for example, can form a symbiotic relationship with plant roots that increases their nutrient and water absorption. This is good. D. No-fungi are ALWAYS good when they interact with other organisms. There's never a downside or negative aspect to such interactions. Both sides always benefit from the relationship.

C. No-fungi are sometimes good, sometimes bad for other organisms. It really depends on which fungus you're talking about and the relationship it has with the other organism. Some fungi, for example, can form a symbiotic relationship with plant roots that increases their nutrient and water absorption. This is good.

Organisms that grow very slowly, are non-curable, are present in very small numbers, or are mixed with a number of other bacteria may still be identified using A. Southern blotting. B. replica plating. C. PCR. D. gas chromatography of fatty acids.

C. PCR.

. Why are molecular methods particularly useful for identification of microbes when they are difficult to grow? A. While all microbes can (and should) be grown for identification purposes, sometimes it's simply faster to use a molecular technique. B. They AREN'T useful-growing a microbe is clearly the only way to properly identify it. C. Since all microbes use DNA, and we can sometimes detect and identify them through even very small amounts of their DNA, molecular methods allow us to identify microbes even when they can't be grown at all. D. Molecular methods are far cheaper methods than growing microbes for identification.

C. Since all microbes use DNA, and we can sometimes detect and identify them through even very small amounts of their DNA, molecular methods allow us to identify microbes even when they can't be grown at all.

A physician sends a stool sample to your lab, and wants to know if there are lactose fermenting microbes in the sample. How might you determine if these microbes are present or not from this mixed-microbe specimen? A. Streak the sample for isolation on Thayer-Martin agar (which contains lactose and particular antibiotics for selectivity). B. Streak the sample for isolation on a blood agar plate (which contains lactose AND red blood cells that enrich the culture for iron). C. Streak the sample for isolation on a MacConkey agar plate (which contains lactose and a pH indicator that turns pink when acid byproducts are present). D. None of the above would work-there's no way to reliably determine this feature from the specimen given.

C. Streak the sample for isolation on a MacConkey agar plate (which contains lactose and a pH indicator that turns pink when acid byproducts are present).

Gram-positive encapsulated diplococci found in sputum is indicative of A. E. coli. B. Pseudomonas. C. Streptococcus pneumoniae. D. Neisseria gonorrhea.

C. Streptococcus pneumoniae.

An illness outbreak occurs in New York City birds in the late 1990s. After a lengthy scientific investigation, the Centers for Disease Control (CDC) determine that the agent causing the birds to die is the West Nile virus. Outbreaks of this illness have been observed in several other countries in Asia and the Middle East across the last 50 years, but not in the United States. With this information, what would be the best categorization of this infectious agent/disease A. This is clearly a reemerging infection. It's been around for a long time, and it is reappearing in a susceptible population again. B. This is clearly a nosocomial infection. It's transmitted from animals to human beings in urban environments. C. This is clearly an emerging infection. It hasn't been around that long, and it has made a jump across continents into a new susceptible population. D. This is clearly not a concern to human beings--maybe it's emerging in animals, maybe it's reemerging, maybe it's nosomial. But who cares? It's only in birds.

C. This is clearly an emerging infection. It hasn't been around that long, and it has made a jump across continents into a new susceptible population.

Scientists recently cloned Louis Pasteur and put him back to work in a modern lab. He promptly developed a gel that breaks down proteins. Since he hasn't been around for some time, he's unsure what the best application for his invention might be. Help him out. What pathogenic item in this gel would be most effective and safe at eliminating? A. Viroids on the surface of agricultural plant tissues B. Prions inside the central nervous system of cows C. Viruses on the surface of the skin D. Bacteria in the intestines of human beings E. The fungus that causes athlete's foot between people's toes

C. Viruses on the surface of the skin

The name Lactococcus (Streptococcus) lactis A. indicates that the subgenus is Streptococcus. B. indicates that the family is Lactococcus. C. indicates that Streptococcus is the old genus name. D. indicates that Lactococcus is the old class name.

C. indicates that Streptococcus is the old genus name.

A newly developed antibiotic drug shows promise by inhibiting prokaryotic 70S ribosomes in initial studies. However, when animal studies are begun, it's noted that it also inhibits growth of animal cells. Aren't prokaryotic ribosomes different from eukaryotic ribosomes? How can this be happening? A. Perhaps the ribosomes aren't as different as we thought, so a drug can affect and impair both of them. B. While the proteins made in the cytosol of eukaryotic cells are, indeed, produced from the 80S eukaryotic ribosome, mitochondria and chloroplasts possess 70S ribosomes. This drug might be impairing the activity of chloroplasts in animal cells. C. While the proteins made in the cytosol of eukaryotic cells are, indeed, produced from the 80S eukaryotic ribosome, mitochondria and chloroplasts possess 70S ribosomes. This drug might be impairing the activity of mitochondria in animal cells. D. Perhaps the scientists accidently combined their cultures of animal and bacterial cells-this might indicate an impairment in growth in the culture. In reality, it's still just impairing the bacterial cells.

C. While the proteins made in the cytosol of eukaryotic cells are, indeed, produced from the 80S eukaryotic ribosome, mitochondria and chloroplasts possess 70S ribosomes. This drug might be impairing the activity of mitochondria in animal cells.

The outbreak of measles within the last few years was due to A. mutation of the virus. B. change in the environment. C. a decline in vaccination of children in the previous years. D. increase in sensitivity of detection techniques.

C. a decline in vaccination of children in the previous years.

MacConkey agar is A. a selective agar. B. a differential agar. C. a selective and differential agar. D. used to distinguish between bacteria by the type of hemolysis observed.

C. a selective and differential agar.

The solidifying agent used most successfully in bacterial nutrient media is A. gelatin. B. peptone. C. agar. D. starch.

C. agar.

Lichens may be an association of A. several different fungi. B. protozoa and bacteria. C. algae and fungus. D. virus and algae.

C. algae and fungus.

Mycobacterium tuberculosis is one of the few species of bacteria that A. are encapsulated. B. stain Gram-negative. C. are acid fast. D. stain Gram-positive.

C. are acid fast.

Prions A. are only composed of RNA. B. are only composed of DNA. C. are only composed of protein. D. cause diseases in plants. E. are only composed of RNA AND cause diseases in plants.

C. are only composed of protein.

Haustoria A. are a form of parasitic protozoan. B. refers to the reproductive structure formed by slime molds. C. are specialized hyphae used by parasitic fungi. D. are the reproductive form of protozoans.

C. are specialized hyphae used by parasitic fungi.

Specimens can be observed at the atomic level using a(n) A. scanning electron microscope. B. transmission electron microscope. C. atomic force microscope. D. All of the choices are correct. E. None of the choices is correct.

C. atomic force microscope.

Organisms that use CO2 as their source of carbon are called A. organotrophs. B. heterotrophs. C. autotrophs. D. chemotrophs.

C. autotrophs.

Products that limit pH changes are often incorporated into media and are referred to as A. enzymes. B. bases. C. buffers. D. acids.

C. buffers.

Plants are dependent on microorganisms for A. providing oxygen. B. providing water. C. changing atmospheric nitrogen to a usable form. D. providing carbohydrates.

C. changing atmospheric nitrogen to a usable form.

APITM, EnterotubeTM, and VitekTM are all A. methods for extracting DNA from bacteria. B. used to measure gas production. C. commercially available methods used to identify bacteria. D. used to show the presence of bacteria in a sample.

C. commercially available methods used to identify bacteria.

Eukaryotic cells are A. less complex than prokaryotic cells. B. members of the Domains Bacteria and Archaea. C. defined by the presence of a membrane bound nucleus. D. able to reproduce more rapidly than prokaryotes. E. less complex than prokaryotic cells, members of the Domains Bacteria and Archaea AND able to reproduce more rapidly than prokaryotes.

C. defined by the presence of a membrane bound nucleus.

Organisms that may cause red tide are A. green algae. B. brown algae. C. dinoflagellates D. euglenids.

C. dinoflagellates

The return of carbon dioxide to the atmosphere and nitrogen to the soil is due to the action of A. viruses and plants. B. bacteria and viruses. C. fungi and bacteria. D. fungi and viruses.

C. fungi and bacteria.

The scientific name of an organism includes its A. family and genus. B. first name and last name. C. genus and species. D. domain. E. genus and species AND domain.

C. genus and species.

Organisms that use organic molecules as their source of carbon are called A. chemotrophs. B. organoheterotrophs. C. heterotrophs. D. autotrophs.

C. heterotrophs.

Outside a cell, viruses are A. running a small number of biochemical reactions. B. synthesizing proteins necessary for entry into the host. C. inactive. D. constructing a cell membrane known as an envelope. E. running a small number of biochemical reactions AND synthesizing proteins necessary for entry into the host.

C. inactive.

If the GC content of two organisms is 45% in both, A. they are definitely related. B. they are definitely not related. C. they may or may not be related. D. the AT content is 65%. E. they are definitely related AND the AT content is 65%.

C. they may or may not be related.

Most solutes pass through the cytoplasmic membrane via A. osmosis. B. diffusion. C. transport proteins. D. secretion.

C. transport proteins.

A new drug is developed that targets and binds to the lipid A portion of LPS from Gram-negative bacterial cells. This drug shows a high degree of activity and binding in a test tube setting against purified lipid A. Based on this information, A. we should fast track this drug and get it out to physicians immediately to help prevent toxic/septic shock in humans. B. we should do some animal testing with whole Gram-negative cells and the drug before we jump to any conclusions. C. we should next proceed by moving to testing in a test tube using whole Gram-negative cells to see if it binds with the same strength. D. we should abandon the drug entirely. Binding to lipid A won't kill the bacteria, so the drug is useless to develop further. It wouldn't help humans who have septic shock at all.

C. we should next proceed by moving to testing in a test tube using whole Gram-negative cells to see if it binds with the same strength.

A urine sample with more than 100,000 organisms is considered indicative of infection. A urine sample containing 5,000 bacteria,with a generation time of 30 minutes, sits for 3 hours before finally being assayed. How many bacteria will then be present within the sample? A. 10,000 B. 64,000 C. 100,000 D. 320,000

D. 320,000

Explain the difference between a biotype and a serotype. A. A biotype is the living type of microorganism identified, while the serotype is an individual's type of blood serum. B. A biotype is the type of biological environment a microbe will grow in, while the serotype is the type of blood serum that the microbe can grow in. C. A biotype is the particular phenotypic traits and characteristic structures of a biological microorganism, while the serotype is the list of molecules the microbe is able to make and secrete into the serum of an infected individual. D. A biotype is the biochemical profile of a particular microorganism, while the serotype is the difference in its surface structures/antigens that will lead to separate immune responses from an organism (characterized by presence of different antibodies in the individual's serum).

D. A biotype is the biochemical profile of a particular microorganism, while the serotype is the difference in its surface structures/antigens that will lead to separate immune responses from an organism (characterized by presence of different antibodies in the individual's serum)

Why are we concerned at all with monitoring emerging/reemerging diseases? A. These represent growing threats to human health that will require new scientific research and resources to effectively combat. B. Because globalization (greater trade and travel between countries) leads to more chances for spread of illnesses into new areas and populations. Monitoring these illnesses will help us to protect people. C. Because the speed of travel has increased greatly. With increased speed of travel, it is far more likely that a serious pathogenic threat from one area of the world can spread rapidly across the globe in a very fast manner. We need to monitor the occurrence of these illnesses to try to protect populations. D. All of the above.

D. All of the above.

7. The opposite results obtained by scientists apparently doing the same experiments in investigating spontaneous generation A. shows the importance of repeating experiments. B. shows the importance of exactly duplicating experimental conditions. C. led to further experiments that ultimately furthered knowledge. D. All of the choices are correct.

D. All of the choices are correct.

Serological methods A. are useful in identifying bacteria. B. rely on the specificity of an antibody-antigen interaction. C. may be simple and rapid. D. All of the choices are correct.

D. All of the choices are correct.

The three domain classification scheme uses A. order, phylum, class. B. plants, animals, bacteria. C. Protista, Prokaryotae, Fungi. D. Archaea, Bacteria, Eukarya.

D. Archaea, Bacteria, Eukarya.

Which term(s) refer(s) to bacterial morphology? A. Bacillus B. Coccus C. Polyhedral D. Coccus AND Bacillus

D. Coccus AND Bacillus

In 1970 Stanier proposed that classification be based on A. evolution. B. Gram stain. C. physiology. D. DNA sequence.

D. DNA sequence.

During which phase of the bacterial growth curve does the total number of viable cells decline? A. Stationary B. Lag C. Exponential D. Death

D. Death

An electron microscope must use electromagnet 'lenses'shaped like donuts to direct the electrons onto the specimen. Why aren't they solid, like the lenses in a light microscope? A. A magnetic field cannot be applied across a completely solid object-there must be an opening within the object for the field to be applied through. B. The user has to be able to physically look through the magnets to focus the beam of electrons onto the specimen, since the metal of the magnets is opaque. Without a hole in the middle, the user wouldn't be able to see! C. The electrons would destroy the electromagnet material unless there was a physical hole for them to travel through on their way to the specimen. D. Electrons are particles, and particles cannot travel through a solid item. The hole in the middle allows them to travel from the source of the electrons to the specimen.

D. Electrons are particles, and particles cannot travel through a solid item. The hole in the middle allows them to travel from the source of the electrons to the specimen.

A breath test assaying for radioactive carbon dioxide may be used to indicate the presence of A. E. coli. B. Pseudomonas. C. Streptococcus pyogenes. D. Helicobacter pylori.

D. Helicobacter pylori.

During which phase of the bacterial growth curve does a bacterial population become much more resistant to harmful conditions? A. Lag phase B. Exponential phase C. Stationary phase D. Late log phase

D. Late log phase

Which of the following bacteria lack a cell wall? A. Treponema pallidum B. Mycobacterium tuberculosis C. Staphylococcus aureus D. Mycoplasma pneumoniae

D. Mycoplasma pneumoniae

Intracellular Gram-negative diplococci found in a urethral sample from a male is indicative of A. E. coli. B. Pseudomonas. C. Streptococcus pneumoniae. D. Neisseria gonorrhoeae.

D. Neisseria gonorrhoeae.

One of the greatest causes of human deaths through time has been due to A. Giardia spp. B. Histoplasma spp. C. Trypanosoma spp. D. Plasmodium spp.

D. Plasmodium spp.

The scientist that contributed most to the development of pure culture techniques was A. Alexander Fleming. B. Louis Pasteur. C. Edward Jenner. D. Robert Koch.

D. Robert Koch.

Which microscope would be the BEST selection for examination of a virus? A. Confocal scanning laser microscope B. Atomic force microscope C. Dark-field light microscope D. Scanning electron microscope

D. Scanning electron microscope

You are in charge of water quality for your city's water treatment plant. Of the methods at your disposal, which will be the most efficient and cheapest method of determining the number of viable bacteria in the water coming out of your plant? A. Direct counts using a microscope and a counting chamber. B. Using a Coulter counter machine. C. Performing serial dilutions of your samples and doing spread plate counts. D. Using membrane filtration followed by placing the membrane in a growth medium for colony counts after incubation. E. Biochemical analysis of secondary metabolites in the water that are given off by bacteria.

D. Using membrane filtration followed by placing the membrane in a growth medium for colony counts after incubation.

Fungal spores are a major cause of A. anaerobic disease. B. fermentation. C. food spoilage. D. asthma.

D. asthma.

Individual atoms on the surface of prepared samples can be observed by using the A. phase contrast microscope. B. scanning electron microscope. C. dark-field microscope. D. atomic force microscope.

D. atomic force microscope.

Prokaryotic cells divide by a process known as A. conjugation. B. mitosis. C. binary fusion. D. binary fission.

D. binary fission.

All fungi have ______ in their cell walls. A. cellulose B. pectin C. peptidoglycan D. chitin

D. chitin

The idea of spontaneous Generation postulated that A. organisms could evolve into the next generation of organisms. B. organisms could spontaneously combust. C. organisms could spontaneously arise from other living organisms. D. living organisms could spontaneously arise from non-living material.

D. living organisms could spontaneously arise from non-living material.

A hot tub (approx. 104F or 40C) would most likely contain A. psychrophiles. B. partiers. C. thermophiles. D. mesophiles.

D. mesophiles.

Fungi are classified according to their A. mode of locomotion. B. morphology. C. mode of nutrition. D. method of sexual reproduction.

D. method of sexual reproduction.

Cellulose is a major component of plants and is only directly digested by A. herbivores. B. carnivores. C. termites. D. microorganisms.

D. microorganisms.

Free-floating, photosynthetic organisms found in marine environments are A. Bucella. B. blue-green algae. C. krill. D. phytoplankton.

D. phytoplankton.

Fungi are particularly adept at infecting A. protozoans. B. algae. C. animals. D. plants.

D. plants.

Gonyaulax A. produces a non-protein neurotoxin. B. infects the nervous system of humans. C. is a dinoflagellate. D. produces a non-protein neurotoxin AND is a dinoflagellate.

D. produces a non-protein neurotoxin AND is a dinoflagellate.

Sarcodina move by means of A. flagella. B. apicomplexans. C. cilia. D. pseudopodia.

D. pseudopodia.

In E. coli O157:H7, the O157:H7 refers to the A. specific type of DNA present. B. specific genus. C. general family. D. the specific LPS and flagella type present.

D. the specific LPS and flagella type present.

A research lab is trying to produce new antibiotics. They come up with drugs that detach the hydrophilic heads from the phospholipids in plasma membranes. This drug A. would be highly toxic and completely useless for human beings-we also have plasma membranes with hydrophilic head groups! B. would be highly toxic only to bacteria, making it an excellent drug to develop and test further. Humans have a different phospholipid structure in their cell plasma membranes than bacteria. C. would generally not be toxic enough to damage Gram-negative bacteria, as their plasma membranes lie under a thick layer of peptidoglycan. D. would be highly toxic for human beings, but might be useful as a topical antibiotic skin cream. The top layer of skin cells is dead anyway, so it wouldn't matter if this damaged those cells. It could NOT be taken internally, though, by human beings.

D. would be highly toxic for human beings, but might be useful as a topical antibiotic skin cream. The top layer of skin cells is dead anyway, so it wouldn't matter if this damaged those cells. It could NOT be taken internally, though, by human beings.

A microbe is discovered growing near a deep sea thermal vent. When researchers bring a sample up to the surface and try to grow it in a lab at room temperature in a normal incubator, they are unsuccessful. Why? A. The pressure isn't the same at sea level as it is on the ocean floor. B. Oxygen concentrations are very different between the two environments-it's possible the microbe is a strict anaerobe and is poisoned by the air (oxygen) in the lab. C. Salt concentrations might be different in the media the researchers are attempting to use and the salt water the microbe is used to living in. This might be causing osmotic pressure differences that the microbe can't tolerate. D. The temperature is probably different-the thermal vent would be very hot, while these researchers are trying to grow this microbe at room temperature. The enzymes in the cells are probably outside of their normal operating range at room temperature, and therefore nonfunctional. E. All of the above.

E. All of the above.

Fungi are important because of their ability to A. help many plants grow. B. cause disease in plants. C. make certain foods and beverages. D. spoil food. E. All of the above.

E. All of the above.

Aflatoxins A. are produced by Aspergillus. B. are possible carcinogens. C. may be found in peanuts. D. are toxins. E. All of the choices are correct.