Microbiology Chapter 1 Test

Microbiology Chapter 1 Test Which of the following statement is FALSE? A) Microbial cells can exist as single cells. B) Microbial cells carry out their life processes of growth independently. C) Microbial cells include both bacteria and viruses. D) Microbial cells are surrounded by a cytoplasmic membrane. - ANS C. Microbial cells include both bacteria and viruses Which of the following statements is correct? A) Microorganisms are significant contributors to the total biomass on Earth. B) Microorganisms represent a much smaller amount of Earth's biomass than plants. C) Microorganisms represent a much smaller amount of Earth's biomass than animals. D) Microorganisms are significant in number, but not in overall biomass. - ANS A. Microorganisms are significant contributors to the total biomass of the Earth Differential selection and decent with modification occurs during a process called A) cellular differentiation. B) evolution. C) growth. D) transformation. - ANS B. evolution In what/which domain(s) of life is/are microorganisms represented? A) Archaea B) Bacteria C) Eukarya D) Archaea, Bacteria, and Eukarya - ANS D. Archaea, Bacteria, and Eukarya Biological catalysts involved in the acceleration of the rate of chemical reactions are called A) catalytic converters. B) growth agents. C) evolutionary molecules. D) enzymes. - ANS D. enzymes Regarding early life on Earth, A) microbial life existed for billions of years before plant and animal life. B) microbial life existed long before animals but has been around for about the same amount of time as plants. C) microbial life, plant life, and animal life all appeared at about the same time. D) it is impossible to determine which type of life first appeared. - ANS A. microbial life existed for billions of years before plant and animal life. The person who described the "wee animalcules" was A) Robert Hooke. B) Antoni van Leeuwenhoek. C) Louis Pasteur. D) Ferdinand Cohn. - ANS B. Antoni van Leeuwenhoek Walther Hesse and ________ pioneered the use of agar as a solidifying agent. A) Louis Pasteur B) Ferdinand Cohn C) Robert Koch D) Sergei Winogradsky - ANS C. Robert Koch Which of the following is/are characteristic of all cellular organisms? A) Communication B) Evolution C) Motility D) Communication, evolution, and motility - ANS B. Evolution Deduce why viruses are excluded from the ribosomal RNA-based tree of life. A) Some viruses contain multiple strands of RNA. B) Their genetic elements cannot be sequenced. C) They can infect other organisms, which complicates the genetic comparisons. D) They lack ribosomal RNA (rRNA). - ANS D. They lack ribosomal RNA (rRNA) Louis Pasteur developed the vaccine(s) for A) anthrax only. B) fowl cholera only. C) rabies only. D) anthrax, fowl cholera, and rabies. - ANS D. anthrax, fowl cholera, and rabies The discovery of antibiotics and other important chemicals led to the field of A) industrial microbiology. B) agricultural microbiology. C) marine microbiology. D) aquatic microbiology. - ANS A. industrial microbiology Microbial sterilization is used to A) decrease the possibility of contaminants growing in a culture. B) kill bacteria but not necessarily viruses or other microbes. C) kill all microbes in or on objects. D) clean a work area. - ANS C. kill al microbes in or on objects Transparent double-sided dishes used for growing microbes are most commonly called A) Petri dishes. B) baker dishes. C) sterilization plates. D) culture medium plates. - ANS A. petri dishes Microbes playing a role in nitrogen fixation in plants live in ________, while those playing a role in the digestive tract of certain herbivores live in ________. A) rumens / nodules B) nodules / rumens C) nodules / fortrans D) fortrans / rumens - ANS B. nodules / rumens Which of the following is NOT an accomplishment of Louis Pasteur? A) Determined that the alcohol-making process was mediated by microbial fermentation and thus refuted the theory of spontaneous generation B) Developed enrichment culture techniques C) Developed heat sterilization techniques that involved the creation of a specialized swan- necked flask D) Developed the first rabies vaccine and treated thousands of individuals - ANS B. Developed enrichment culture techniques The theory of spontaneous generation was refuted by the work of A) Louis Pasteur. B) Robert Koch. C) Robert Hooke. D) Antoni van Leeuwenhoek. - ANS A. Louis Pasteur A Pasteur flask has a(n) A) swan neck to prevent particulate matter from getting into the main body of the flask. B) double neck so two substances may be added at the same time. C) secondary opening at the base to allow for drainage. D) inverted upper edge to prevent spillage while swirling. - ANS A. swan neck to prevent particulate matter from getting into the main body of the flask. Predict how Pasteur's conclusions on spontaneous generation with swan flasks would have changed if he worked with and maintained the flasks in a sterile laminar flow hood. A) Sterilization of the swan flask solutions would not have been necessary to reject spontaneous generation. If he did sterilize the flasks, the spontaneous generation hypothesis would have been supported. B) His incubation times would not have been sufficient to refute spontaneous generation. C) Pasteur's flasks never would have putrefied, and the experiment would not have refuted spontaneous generation. D) Viruses would have still been present, and his conclusion would have been unchanged. - ANS C.Pasteur's flasks never would have putrefied, and the experiment would not have refuted spontaneous generation. A pure culture A) is sterile. B) is a population of identical cells. C) is made of a clearly defined chemical medium. D) contains one microbial cell. - ANS B. is a population of identical cells Martinus Beijerinck was the first to isolate A) green algae. B) certain nitrogen-fixing root nodule bacteria. C) certain sulfate-reducing bacteria. D) green algae, certain nitrogen-fixing root nodule bacteria, and certain sulfate-reducing bacteria. - ANS D. green algae, certain nitrogen-fixing root nodule bacteria, and certain sulfate-reducing bacteria. Chemolithotrophy involves A) oxidation of organic compounds. B) oxidation of inorganic compounds. C) reduction of organic compounds. D) metabolic autotrophy. - ANS B. oxidation of inorganic compounds. Developments in the fields of immunology and medical microbiology were practical extensions of the work of A) Sergei Winogradsky. B) Antoni van Leeuwenhoek. C) Joseph Lister. D) Robert Koch. - ANS D. Robert Koch Microbial control in wastewaters would most logically be a part of A) microbial genetics. B) aquatic microbiology. C) medical microbiology. D) bacterial energetics. - ANS B. aquatic microbiology Robert Koch contributed to the field of microbiology by being the first person to A) develop the tuberculin test only. B) formulate four postulates for definitively linking a specific microorganism to a specific disease only. C) use agar as a solidifying agent in growth media only. D) develop the tuberculin test, formulate four postulates for definitively linking a specific microorganism to a specific disease, and use agar as a solidifying agent in growth media. - ANS D. develop the tuberculin test, formulate four postulates for definitively linking a specific microorganism to a specific disease, and use agar as a solidifying agent in growth media. Mycobacterium tuberculosis is very difficult to stain because of the A) presence of ribosomes in the cytoplasm. B) location of the DNA within the cell. C) large amounts of a waxlike lipids present in its cell wall. D) lack of a cell wall. - ANS C. large amounts of a waxlike lipids present in its cell wall. Louis Pasteur's most famous success was his work on A) Mycobacterium tuberculosis. B) the rabies vaccine. C) optical isomers. D) cultivation of E. coli. - ANS B. the rabies vaccine. Microorganisms play key roles in the cycling of important nutrients in plant nutrition, particularly those of A) carbon only. B) nitrogen only. C) sulfur only. D) carbon, nitrogen, and sulfur. - ANS D. carbon, nitrogen, and sulfur. Microbial ecology is the study of A) microbial processes in the rhizosphere that benefit plant growth. B) the diversity and activities of microorganisms. C) the grouping and classifying of microorganisms. D) microorganisms in their natural environments. - ANS D. Microorganisms in their natural environments The structure that confers structural strength on the cell is known as the A) cytoplasmic membrane. B) cell wall. C) ribosome. D) cytoplasm. - ANS B. cell wall A microbial cell's membrane is considered ________, because its internal constituents are maintained within the cell. However, it also imports and exports other molecules in response to its environment. A) differential B) microselective C) rigid D) semipermeable - ANS D. Semipermeable Some microorganisms can undergo ________ in which various cell types can become specialized and arise from one parent cell type. A) differentiation B) genetic exchange C) maturation D) mutagenesis - ANS A. Differentiation Cyanobacteria and purple sulfur bacteria both obtain energy from light. However, only the ________ are capable of releasing ________. A) cyanobacteria / organic compounds B) cyanobacteria / oxygen C) purple bacteria / organic compounds D) purple bacteria / oxygen - ANS B. cyanobacteria / oxygen The process whereby microorganisms are used to help clean up pollution created by human activities is known as A) bioaugmentation. B) biodegradation. C) bioengineering. D) bioremediation. - ANS D. Bioremediation Bacillus anthracis deficient in its ability to differentiate would not be able to A) chemotax toward growth substrates. B) create vesicles. C) form spores. D) grow without additional supplemented nutrients. - ANS C. form spores Microbial biochemistry most specifically involves the discovery of microbial ________ and the ________ they perform. A) organelles / diffusion B) enzymes / organelles C) reactions / enzymes D) macromolecules / functions - ANS D. macromolecules / functions Microbial cells first evolved on Earth approximately ________ billion years ago. A) 1.6 to 1.8 B) 3.8 to 4.3 C) 5.4 to 5.6 D) 7.0 to 7.2 - ANS B. 3.8 to 4.3 The first documented description of a microorganism was of a ________ by ________. A) bacterium / Ferdinand Cohn B) fungus / Robert Koch C) mold / Robert Hooke D) yeast / Martinus Beijerinck - ANS C. mold/Robert Hooke ________ produced by microbial fermentation of glucose from cellulose or cornstarch is becoming a more important component of biofuels in the United States, and specialized ________ are needed to make this a commercially available product. A) Biodiesel / biotechnologists B) Biodiesel / industrial microbiologists C) Ethanol / biotechnologists D) Ethanol / industrial microbiologists - ANS D. Ethanol/ industrial microbiologists ________ was the first to describe microorganisms, while ________ was the first person to see bacteria. A) Antoni van Leeuwenhoek / Robert Hook B) Antoni van Leeuwenhoek / Robert Koch C) Robert Hooke / Antoni van Leeuwenhoek D) Robert Koch / Antoni van Leeuwenhoek - ANS C. Robert Hooke / Antoni van Leeuwenhoek The production of human proteins (e.g., insulin) by genetically engineered microorganisms is an example of ________, a subdiscipline of microbiology. A) applied microbiology B) biotechnology C) industrial microbiology D) molecular microbiology - ANS B. biotechnology Approximately two billion years ago, ________ were primarily responsible for initially oxygenating Earth. A) algae B) Archaea C) cyanobacteria D) purple sulfur bacteria - ANS C. Cyanobacteria Archaea and Bacteria are unified as prokaryotes in lacking ________ which Eukarya contain, such as mitochondria. A) membranes B) nuclei C) membrane-enclosed organelles D) nuclei and membrane-enclosed organelles - ANS D. nuclei and membrane-enclosed organelles Bioremediation ________ by introducing pollutant-consuming microorganisms or specific nutrients that help microorganisms degrade pollutants. A) accelerates the natural cleanup process B) exploits genetic exchange mechanisms C) invokes microbial evolution D) uses chemotaxis of biodegrading microorganisms - ANS A. accelerates the natural cleanup process Electron microscopy has greater ________ than light microscopy, because the wavelength of visible light is much larger than the wavelength of electrons. A) contrast B) magnification C) resolution D) penetration - ANS C. resolution Which of the following types of microscopy is especially effective for viewing details of internal structures within live cells? A) Phase-contrast microscopy B) Transmission electron microscopy C) Bright-field microscopy D) Scanning electron microscopy - ANS A. Phase-contrast microscopy Which of the following types of microscopy could be used to visualize the layers of the cell membrane and the cell wall? A) Phase-contrast microscopy B) Transmission electron microscopy C) Bright-field microscopy D) Confocal microscopy - ANS B. Transmission electron microscopy When medical devices are left in the body, bacteria may grow on them as ________, which makes them especially resistant to treatment. A) biofilms B) liquids C) populations D) communities - ANS A. biofilms Microbes that live at high temperatures in hot springs are A) always Archaea. B) also able to thrive at low temperatures. C) called extremophiles. D) rarely found. - ANS C. called extremophiles Why is ribosomal RNA especially useful for the study of phylogenetic relationships? A) It is only found in some species, helping them to distinguish from others. B) It is highly conserved. C) It is highly variable. D) It is extremely short. - ANS B. It is highly conserved. Why is it important to use cultivation-independent methods to help understand microbial diversity? A) It allows researchers to identify species that cannot be grown in culture. B) It is the only way that phylogenetic trees can be constructed. C) It must be used after bacteria are cultured to more fully sequence their DNA. D) It is necessary to be able to examine ribosomal RNA. - ANS A. It allows researchers to identify species that cannot be grown in culture. Compared to Eukaryotes, Bacteria and Archaea have ________ surface-to-volume ratios, causing ________ nutrient exchange. A) lower / lower B) lower / higher C) higher / lower D) higher / higher - ANS D. higher/higher An organism of the genus Staphylococcus is ________, while an organism of the genus Spirochaeta is ________. A) spherical / rod shaped B) rod shaped / coiled C) spherical / coiled D) coiled / spherical - ANS C. spherical/ coiled The morphology of a cell influences its A) motility. B) metabolism. C) surface-to-volume ratio. D) motility and surface-to-volume ratio. - ANS D. motility and surface-to-volume ratio. The environment in which a microbial population lives is called its habitat. - ANS True Differentiation occurs only in multicellular organisms. - ANS False Today, the enrichment culture technique developed over a century ago by Martinus Beijerinck remains a feasible approach to discovering bacteria capable of degrading pollutants. - ANS True Viewing the shape of a bacterial or archaeal cell using a microscope gives a great deal of information about the metabolism and lifestyle of the organism. - ANS False