Test Bank For Microbiology: An Introduction Plus Mastering Microbiology, 13th Edition By Gerard J. Tortola| Microbiology: An Introduction Plus Mastering Microbiology, 13th Edition Test Bank|

Chapter 1 The Microbial World and You Multiple-Choice Questions 1) Microorganisms are involved in each of the following processes EXCEPT A) infection. B) decomposition of organic material. C) O2 production. D) food production. E) smog production. 5 2) Each of the following organisms would be considered a microbe EXCEPT A) yeast. B) protozoan. C) bacterium. D) mushroom. E) virus. 3) The term used to describe a disease-causing microorganism is A) microbe. B) bacterium. C) virus. D) pathogen. E) infection. 4) Common commercial benefits of microorganisms include synthesis of A) riboflavin. B) acetone. C) insulin. D) aspirin. E) riboflavin, acetone and insulin. 5) What factors contribute to the rising incidence of antibiotic resistance? A) overuse of the specific drugs B) misuse of the specific drugs C) random mutations in bacterial genomes D) random mutations, overuse and misuse of specific drugs E) overuse and misuse of specific drugs 4.1 9 5 6) The formal system for classifying and naming organisms was developed by A) Robert Koch. B) Ignaz Semmelweis. C) Aristotle. D) Carolus Linnaeus. E) Louis Pasteur. 7) In the name Staphylococcus aureus, aureus is the A) genus. B) domain name. C) species. D) kingdom. E) family name. 8) A prokaryotic cell may possess each of the following cellular components EXCEPT A) flagella. B) a nucleus. C) ribosomes. D) a cell wall. E) a cell membrane. 9) Which of the following is NOT associated with viruses? A) organelles B) nucleic acid C) envelope D) chemical reactions E) protein coat 10) Figure The bacterial shape of the cells in the scanning electron micrograph shown in Figure would best be described as A) bacillus. B) spiral. C) coccus. D) ovoid. E) columnar. 11) Protozoan motility structures include A) cilia. B) flagella. C) pseudopods. D) cilia and pseudopods only. E) cilia, flagella, and pseudopods. 12) Viruses are not considered living organisms because they A) cannot reproduce by themselves. B) are structurally very simple. C) can only be visualized using an electron microscope. D) are typically associated with disease. E) are ubiquitous in nature. 13) Microbes that live stably in and on the human body are called the A) transient microbiota. B) human microbiome. C) pathogenic microorganisms. D) virulent microorganisms. E) opportunistic microbiota. 14) Which of the following is NOT a domain in the three-domain system? A) animalia B) archaea C) bacteria D) eukarya 15) A system of classification grouping organisms into 3 domains based on the cellular organization of organisms was devised by A) Carolus Linnaeus. B) Anton van Leewenhoek. C) Carl Woese. D) Louis Pasteur. E) Robert Koch. 16) Archaea differ from bacteria in that archaea A) have cell walls composed of substances other than peptidoglycan. B) lack nuclei. C) use organic compounds for food. D) reproduce by binary fission. E) are prokaryotic. 17) Who is credited with first observing cells? A) Robert Hooke B) Anton van Leeuwenhoek C) Robert Koch D) Louis Pasteur E) Carolus Linnaeus 18) Who is credited with first observing microorganisms? A) Robert Hooke B) Anton van Leeuwenhoek C) Robert Koch D) Louis Pasteur E) Carolus Linnaeus 19) Biogenesis refers to the A) spontaneous generation of organisms from nonliving matter. B) development of life forms from preexisting life forms. C) development of aseptic technique. D) germ theory of disease. 20) If you were setting up an experiment to disprove spontaneous generation in a liquid medium, which of the following would be essential to the experiment? A) supplying the liquid with nutrients B) starting with a liquid that contains microorganisms C) adding antibiotics to the liquid D) using a sterile liquid and eliminating exposure to microorganisms E) adding carbon dioxide to the liquid 21) The arguments supporting spontaneous generation were finally disproved by A) Louis Pasteur. B) Francesco Redi. C) Rudolf Virchow. D) John Needham. E) Lazzaro Spallanzani. 22) Regarding Louis Pasteur's experiments with the S-neck flask, which of the following statements is TRUE? A) Air exchange was involved. B) A food source was provided. C) The possibility of contamination was removed. D) All preexisting microorganisms were killed. E) Air exchange occurred, a food source was provided, preexisting microorganisms were killed and contamination was prevented 23) The microbial process of converting sugars to alcohol is known as A) fermentation. B) pasteurization. C) tyndallization. D) lyophilization. E) alcoholism. 3.1 24) Proof that a microbe could cause disease was provided by A) Pasteur. B) Lister. C) Koch. D) Wasserman. E) Semmelweis. 0 25) The use of phenol (carbolic acid) as a wound disinfectant was first practiced by A) Lister. B) Semmelweis. C) Pasteur. D) Holmes. E) Koch. 3.4 1.9 26) Mycology is the study of A) mycoplasma. B) mushrooms. C) protozoa. D) molds. E) molds, yeast, and mushrooms. 3 27) The first step for directly linking a microbe to a specific disease according to Koch's postulates is to A) culture the blood or other body fluid from a diseased animal using nutrient medium. B) inject a sample of blood or other body fluid from a diseased animal into a healthy animal. C) obtain a sample of blood or other body fluid from a diseased animal. D) compare the blood of a sick animal to blood obtained from a healthy animal. E) isolate microbes from the blood of healthy animals. 0 28) In which of the following situations would Koch's postulates be utilized? A) determination of the cause of a new emerging disease by scientists studying disease transmission B) development of a new antibiotic in a pharmaceutical lab C) determination of the cause of cancer in a patient D) formulation of a vaccine against a new pathogen in a genetic engineering lab E) whenever the scientific method is used to investigate a microbiological problem 0 5 29) Robert Koch identified the cause of A) smallpox. B) anthrax. C) diphtheria. D) AIDS. E) rabies. 0 5 30) Which physician is first associated with vaccination? A) Ehrlich B) Jenner C) Lister D) Koch E) Escherich 1 5 31) Which of the following findings was essential for Edward Jenner's vaccination process? A) Exposure to a milder disease form may produce immunity. B) A weakened microorganism will not cause disease. C) Someone who recovers from a disease will not acquire that disease again. D) Disease is caused by viruses. E) Pathogenic microorganisms infect all humans and animals in the same manner. 1 5 32) Penicillin was discovered by accident by A) Alexander Fleming. B) Paul Ehrlich. C) Edward Jenner. D) Robert Koch. E) Joseph Lister. 3.4 2 5 33) Who was the first scientist to pursue a "magic bullet" that could be used to treat infectious disease? A) Jenner B) Pasteur C) Ehrlich D) Lister E) Semmelweis 3.4 2 5 34) Fungal infections are studied by A) virologists. B) bacteriologists. C) parasitologists. D) mycologists. E) herpetologists. 3 35) When our bodies overcome the offensive tactics of a particular microorganism, this is referred to as A) therapy. B) colonization. C) disease. D) resistance. E) deficiency. 7 36) Recombinant DNA refers to the A) study of bacterial ribosomes. B) study of the function of genes. C) interaction between human and bacterial cells. D) synthesis of proteins from genes. E) DNA resulting when genes from one organism are inserted into another organism. 4.5 4 37) Molecular biology includes the study of A) DNA synthesis. B) RNA replication. C) protein synthesis. D) enzyme function. E) how genetic information directs protein synthesis. 4.2 4 38) Microorganisms are essential to our life. Each of the following is an example of a beneficial function of microorganisms EXCEPT A) alternative fuel production. B) bioremediation. C) gene therapy. D) agriculture. E) increased number of illnesses. 5 5 39) The major food producers for other living organisms is/are A) higher plants. B) cyanobacteria. C) algae. D) higher plants and algae. E) higher plants, cyanobacteria, and algae. 6.1 5 40) Gene therapy is currently used to treat all of the following diseases EXCEPT A) severe combined immunodeficiency disease (SCID). B) Duchenne's muscular dystrophy. C) cystic fibrosis. D) LDL-receptor deficiency. E) colon cancer. 6 5 41) Recombinant DNA technology has become an increasingly important part of our life. It is used for all of the following EXCEPT A) vaccine production. B) enhancing food longevity. C) synthesis of water. D) drug production. E) increasing the nutritional value of food. 6 5 42) Normal microbiota A) indefinitely colonize the body. B) take up residence in sites such as the colon and mouth. C) almost always cause disease in the host. D) are normally found in blood. E) both indefinitely colonize the body and take up residence in sites such as the colon and mouth. 43) Which of the following statements about biofilms is FALSE? A) Compared to free-living bacteria, biofilms are more sensitive to antibiotics. B) Biofilms in pipes can block the flow of water. C) Biofilms in your body protect mucous membranes from harmful microbes. D) Biofilms on medical devices cause infections. E) Biofilms on rocks provide food for animal life. 6.1 8 44) Development of emerging infectious disease can be a result of all of the following EXCEPT A) microbial mutation. B) modern transportation. C) use of genetically modified foods. D) changes in the environment. E) overuse of antibiotics. 9 45) Who challenged the idea of spontaneous generation with the concept of biogenesis? A) Louis Pasteur B) Rudolf Virchow C) Anton van Leewenhoek D) John Needham E) Francesco Redi 46) All of the following are true concerning emerging infectious diseases EXCEPT A) they always involve sporadic cases in endemic areas. B) they include newly described infectious agents. C) known pathogens develop evolutionary changes. D) known diseases spread to new regions or populations. E) they result from human exposure to a pathogen due to ecological changes. 9 47) Microorganisms are beneficial to humans in all of the following ways EXCEPT A) marine and freshwater organisms form the basis of the food web. B) soil microorganisms break down matter. C) some microorganisms live symbiotically with plants and transform nitrogen gas into organic compounds. D) Pseudomonas, molds and other microorganisms break down lettuce and strawberries at refrigeration temperatures. E) Fermenting microorganisms produce yogurt and sauerkraut from milk and cabbage. 48) What mistake did John Needham make that caused him to conclude that spontaneous generation for microorganisms occurred? A) He failed to seal his flasks of boiled broth. B) He allowed his assistant to conduct the experiment which he did not monitor closely. C) He did not boil his broth solutions, only warmed them. D) He re-contaminated his boiled broth solutions. E) He destroyed the vital force in the solutions. 49) From the list below, which would NOT be considered an emerging pathogen? A) Zika virus B) Avian influenza C) smallpox virus D) Ebola virus E) Lyme disease 9 50) All of the below are examples of a biofilm EXCEPT A) archaea as part of the plankton community in the open ocean. B) dental plaque. C) vegetations on a patient heart valve. D) slimy layer on riverbed rocks. E) infection of a patient catheter. 5.2 8 True/False Questions 1) Infectious disease is almost totally eradicated in our world. 9 2) A student has obtained a sample of pond water for study. Using the high-power lens, he observes several cells with nuclei. He can conclude that the cells are NOT bacteria. 14 3) The process of pasteurization to reduce food spoilage utilizes high heat to kill all bacteria present. 3.4 5 4) Anton van Leeuwenhoek was the first microbiologist to use a microscope to examine environmental samples for the presence of microorganisms. 5) Spontaneous generation refers to living cells arising only from other living cells. 6) Microbes are associated with life-sustaining benefits as well as life-threatening diseases. 7) All cells possess a cell wall. 8) All pathogens known to infect humans have been identified at this point in time. 9 9) The first antibiotic was discovered by Paul Ehrlich. 2 10) Enzymes from Bacillus organisms are used to remove spots on clothing. 5 Essay Questions 1) What is an emerging disease, and what are some of the sources for these "new" infectious diseases? 9 8 2) Compare and contrast prokaryotic and eukaryotic cells. Analyzing 2.4 8 3) What was the function and importance of S-necked flasks in Louis Pasteur's experiments in disproving spontaneous generation? 5 4) Explain the germ theory of disease and discuss why this theory is essential to the treatment of infectious disease. 1.9 5 5) Explain the concept of the formation and maintenance of the human microbiome and discuss the effect of the microbiome on transient microbiota and potential pathogens. 8 Microbiology: An Introduction, 13e (Tortora et al.) Chapter 2 Chemical Principles Multiple-Choice Questions 1) Which of the following statements about the atom is C FALSE? A) It has 6 protons in its nucleus. B) It has 12 neutrons in its nucleus. C) It has 6 electrons orbiting the nucleus. D) Its atomic number is 6. E) Its atomic weight is 12. 2 2) Table O C H Using the information in Table , calculate the molecular weight of ethanol, C2H5OH. A) 96 B) 46 C) 34 D) 33 E) The answer cannot be determined. 2 3) Antacids neutralize acid by the following reaction. Identify the salt in the following equation: Mg(OH)2 + 2HCl → MgCl2 + H2O A) Mg(OH)2 B) HCl C) MgCl2 D) H2O E) None of the answers is correct. 2.4 2.5 4) Which of the following statements is FALSE? A) Salts readily dissolve in water. B) Water molecules are formed by hydrolysis. C) Water freezes from the top down. D) Water is formed as a part of a dehydration synthesis reaction. E) Water is a polar molecule. 2.4 2.4 5) Which of the following is the type of bond holding K+ and I- ions in KI? A) ionic bond B) covalent bond C) hydrogen bond 2.2 2.2 6) Which of the following is the type of bond between molecules of water in a beaker of water? A) ionic bond B) covalent bond C) hydrogen bond 2.2 2.2 7 7) What is the type of bond holding hydrogen and oxygen atoms together in a single H2O molecule? A) ionic bond B) covalent bond C) hydrogen bond 2.2 2.2 8) Identify the following reaction: Glucose + Fructose → Sucrose + Water A) dehydration synthesis reaction B) hydrolysis reaction C) exchange reaction D) reversible reaction E) ionic reaction 2.5 Analyzing 2.7 9) Identify the following reaction: Lactose + H2O → Glucose + Galactose A) dehydration synthesis reaction B) hydrolysis reaction C) exchange reaction D) reversible reaction E) ionic reaction 2.5 Analyzing 2.7 10) Identify the following reaction: HCl + NaHCO3 → NaCl + H2CO3 A) dehydration synthesis reaction B) hydrolysis reaction C) exchange reaction D) reversible reaction E) ionic reaction Analyzing 2 11) Identify the following reaction: NH4OH ⇌ NH3 + H2O A) dehydration synthesis reaction B) hydrolysis reaction C) exchange reaction D) reversible reaction E) ionic reaction Analyzing 2 12) Which type of molecule contains the alcohol glycerol? A) carbohydrate B) phospholipids C) DNA D) protein 2.5 2.9 13) Which type of molecule is composed of (CH2O) units? A) carbohydrate B) lipid C) nucleic acid D) protein 2.5 2.8 14) Which type of molecule contains -NH2 (amino) groups? A) carbohydrate B) triglycerides C) nucleic acid D) protein 2.5 0 15) Which type of molecule NEVER contains a phosphate group? A) triglycerides B) phospholipid C) nucleic acid D) ATP 2.5 2.9 16) Based upon the valence numbers of the elements magnesium (2) and hydrogen (1), predict how many covalent bonds would form between these atoms to achieve the full complement of electrons in their outermost energy shells. A) one B) two C) three D) four 2.2 Analyzing 2.2 2 17) Table O C H Using the information in Table , calculate the number of moles in 92 grams of ethanol, C2H5OH. A) 1 B) 2 C) 3 D) 4 E) The answer cannot be determined. 2.2 Analyzing 2.2 4 18) Which of the following statements regarding protein structure is FALSE? A) The primary structure is formed by covalent bonding between amino acid subunits. B) Secondary structures are formed only from hydrogen bonds. C) Tertiary structures are formed only from covalent bonds. D) Quaternary structures involved multiple polypeptides. 2.5 0 19) Which of the following pairs is mismatched? A) NaOH ⇌ Na+ + OH- is a base B) HF ⇌ H+ + F- is an acid C) MgSO4 ⇌ Mg2+ + is a salt D) KH2PO4 ⇌ K+ + H2 is an acid E) H2SO4 ⇌ 2H+ + is an acid 2.4 Analyzing 2.5 2 20) Table 2.2 NaOH ⇌ Na+ + OH- is a base HF ⇌ H+ + F- is an acid MgSO4 ⇌ Mg2+ + is a salt KH2PO4 ⇌ K+ + H2 is an acid H2SO4 ⇌ 2H+ + is an acid Which of the following statements about the reactions in Table 2.2 is FALSE? A) They are exchange reactions. B) They are ionization reactions. C) They occur when the reactants are dissolved in water. D) They are dissociation reactions. E) They are reversible reactions. Analyzing 2 21) What is the type of weak bond between the hydrogen of one molecule and the nitrogen of another molecule, where the two don't actively share an electron? A) ionic bond B) covalent bond C) hydrogen bond D) disulfide bond E) hydrophobic bond 2.2 2.2 7 22) What is the type of strong chemical bond between carbon, hydrogen, and oxygen atoms in a single organic molecule? A) ionic bond B) covalent bond C) hydrogen bond 2.2 2.2 7 23) What is the type of bond between ions in salt? A) ionic bond B) covalent bond C) hydrogen bond 2.2 2.2 7 24) A scientist wants to perform a test that will indicate whether a nucleic acid sample is composed of either RNA or DNA. Testing for the presence of which of the following is most appropriate in this situation? A) phosphate B) nitrogen C) guanine D) uracil E) thymine 2.5 1 2 25) Structurally, ATP is most like which type of molecule? A) carbohydrate B) lipid C) protein D) nucleic acid 2.5 2 26) What do genes consist of? A) carbohydrates B) lipids C) proteins D) nucleic acids 2.5 1 7 27) Which molecule is composed of a chain of amino acids? A) carbohydrate B) lipid C) protein D) nucleic acid 2.5 0 28) Which are the primary molecules making up plasma membranes in cells? A) carbohydrates B) lipids C) proteins D) nucleic acids 2.5 2.9 7 29) The antimicrobial drug imidazole inhibits sterol synthesis. This would most likely interfere with A) bacterial cell walls. B) fungal cell walls. C) eukaryotic plasma membranes. D) prokaryotic plasma membranes. E) genes. 2.5 Analyzing 3.4 2.9 2 Figure 30) In Figure , which is an alcohol? A) a B) b C) c D) d E) e 2.5 Analyzing 2.7 3 31) Which compound in Figure is an ester? A) a B) b C) c D) d E) e 2.5 Analyzing 2.7 3 32) Which compound in Figure is an organic acid? A) a B) b C) c D) d E) e 2.5 Analyzing 2.6 3 33) Most amino acids found in cells demonstrate what type of chirality? A) L-isomers B) D-isomers C) C-isomers D) B-isomers E) A-isomers 2.5 0 34) Figure What kind of bond is at the arrow in Figure ? A) disulfide bridge B) double covalent bond C) hydrogen bond D) ionic bond E) peptide bond 2.5 Analyzing 0 3 35) An E. coli culture that has been growing at 37°C is moved to 25°C. Which of the following changes must be made in its plasma membrane to help it cope with the decrease in temperature? A) The number of phosphate groups must increase. B) The viscosity must increase. C) The number of saturated chains must increase. D) The number of unsaturated chains must increase. E) No changes are necessary. 2.5 2.9 36) Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be followed. Assume Saccharomyces cerevisiae is grown in a nutrient medium containing the radioisotope 35S. After a 48-hour incubation, the 35S would most likely be found in the S. cerevisiae's A) carbohydrates. B) nucleic acids. C) water. D) lipids. E) proteins. 2.5 0 2 37) Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be followed. Assume Saccharomyces cerevisiae is grown in a nutrient medium containing the radioisotope 32P. After a 48-hour incubation, the majority of the 32P would be found in the S. cerevisiae's A) plasma membrane. B) cell wall. C) water. D) proteins. E) carbohydrates. 2.5 2.9 2 38) Starch, dextran, glycogen, and cellulose are polymers of A) amino acids. B) glucose. C) fatty acids. D) nucleic acids. E) acids. 2.5 2.8 39) Which of the following is a base? A) C2H5OCOOH → H+ + C2H5OCOO- B) C2H5OH C) NaOH → Na+ + OH- D) H2O → H+ + OH- E) H2CO 2.4 Analyzing 25 2 40) Two glucose molecules are combined by a dehydration synthesis reaction to make a maltose molecule. What is the chemical formula for maltose? A) C3H6O3 B) C6H12O6 C) C12H24O12 D) C12H22O11 E) C12H23O10 2.5 2.8 3 41) If an amino acid contained a large hydrocarbon (a group of multiple carbons and hydrogens linked together) as its side group, in which of the following categories could it be appropriately designated? A) hydrophilic B) polar C) nonpolar D) basic E) acidic 2.5 Analyzing 0 2 42) Identify the two functional groups that interact to form a peptide bond. A) amino group and carboxyl group B) carboxyl group and ester group C) amino group and ester group D) ester group and hydroxyl group E) hydroxyl group and amino group 2.5 0 43) A dehydration synthesis reaction between glucose (C6H12O6) and fructose (C6H12O6) produces a molecule of sucrose (C12H22O11). Why don't the two individual molecular formulae add up to the same number of atoms in the sucrose product? A) Oxygen must be burned/consumed during the reaction. B) In a dehydration reaction, a water molecule (H2O) is removed from the final molecule formed. C) In a dehydration reaction, a water molecule (H2O) is added to the final molecule formed. D) Hydrogen must be burned/consumed during the reaction. 2.5 2.7 44) In terms of similarities, which two molecules would be isomers of each other? A) glucose and sucrose B) glucose and maltose C) sucrose and fructose D) fructose and glucose 2.5 2.8 45) Subtle differences exist in the plasma membrane molecules of the organisms in the three Domains. _______ functional groups are found in the plasma membrane molecules of bacteria and eukarya, while ________ functional groups are found in the plasma membrane molecules of archaea. A) amino; carboxyl B) ether; ester C) ester; ether D) ketone; aldehyde E) aldehyde; ketone 2.5 2.9 46) What is the main/most important factor that differentiates methanol, ethanol, and isopropanol from each other? A) the specific location of the hydroxyl functional group B) the number of carbon atoms in the molecule C) the number of hydrogen atoms in each molecule D) the location of the carboxyl functional group E) the number of hydroxyl functional groups present 2.5 2.7 47) A friend tells you that he recently read an article claiming that you need to work to restore the alkalinity of your blood to remain healthy. Why is this impossible and impractical (and unhealthy even if you could make it happen)? A) The normal pH of human blood is in the acidic range, so making it alkaline would kill you. B) Blood is usually around the neutral (pH 7) range, not the alkaline range, in healthy human beings. C) Blood contains buffers that prevent the pH from changing too drastically, so trying to forcibly alter blood pH wouldn't work effectively. D) The normal pH of human blood is already in the alkaline range, so it isn't necessary to "restore" it to that point. E) Blood is usually around the neutral (pH 7) range, not the alkaline range, in healthy human beings AND blood contains buffers that prevent the pH from changing too drastically, so trying to forcibly alter blood pH wouldn't work effectively. 2.4 2.5 48) Which one of the following microbes would grow best at pH 1-3.5? A) Cyanobacteria in ocean water B) Propionibacterium acnes bacteria on human skin C) Acidithiobacillus ferrooxidans in the runoff from a copper mine 2.4 3.3 2.5 49) You put a spoonful of table salt, NaCl, into a glass of water and it dissolves. You repeat this test, but drop the spoonful of salt into a glass of vegetable oil instead. What happens, and why? A) The salt doesn't dissolve because oil is nonpolar, and couldn't dissociate the ionic bond between the Na+ and Cl- ions. B) The salt dissolves in the oil just the same as it did in the water. C) The salt dissolves in the oil, but takes much longer to do so because oil molecules move more slowly than water, slowing the dissolution process down. D) The salt doesn't dissolve because oil is polar, and only nonpolar solvents would cause the dissociation of the Na+ and Cl- ions in the table salt. 2.2 2.2 50) Which one of the following would be the most difficult covalent bond to break in a chemical reaction? A) Na+ and Cl- in NaCl B) two oxygen atoms in a molecule of O2 C) two nitrogen atoms in a molecule of N2 D) two hydrogen atoms in a molecule of H2 2.2 2.2 2.2 True/False Questions 1) Elements only achieve the full complement of electrons in outermost energy shells by donating away or sharing electrons. 2) Covalent bonds are always shared equally. 2.2 2.2 7 3) Individual covalent bonds are stronger than individual ionic bonds. 2.2 2.2 4) All chemical reactions are, in theory, reversible. 5) The formation of ADP from ATP can be defined as a hydrolytic reaction. 2.5 2 6) The density of liquid water is greater than the density of ice. 2.4 2.4 7) A basic solution is expected to contain more hydrogen ions than hydroxyl ions. 2.4 2.5 7 8) All forms of life function optimally at a pH of 7. 2.4 2.5 9) Water has recently been discovered to be lying just underneath the soil on Mars. This means it is possible life as we know it may also exist (or may once have existed) on Mars. 2.4 2.4 2 10) Carbon dioxide is an organic molecule. 2.4 2.6 2 Essay Questions 1) Describe how the properties of phospholipids make these molecules well suited for plasma membranes. 2.5 2.9 8 2) Figure 2.5 Use Figure 2.5 to answer the following. Starch, cellulose, dextran, and glycogen are polysaccharides. How are they similar? To what are their different properties due? Why can't an enzyme that hydrolyzes starch degrade cellulose? 2.5 2.8 8 3) Compare a molecule of a nucleotide to ATP. Could a cell simply insert ATP into DNA without altering it? Explain. 2.5 2 8 4) A scientist claims that when a protein is denatured, it can be expected that its secondary structure will more likely be retained when compared to all other levels of protein structure structures. Do you agree? Explain. 2.5 Creating 0 8 5) Water has recently been found just beneath the soil on Mars, but in frozen form. What does this mean for both the prospect of finding life on Mars in some form, but also for the possibility of humans to survive on/colonize the surface of Mars? 2.4 2.4 2 Microbiology: An Introduction, 13e (Tortora et al.) Chapter 3 Observing Microorganisms Through a Microscope 3.1 Multiple-Choice Questions 1) Which of the following is NOT equal to 1 mm? A) 0.001 m B) 1,000,000 nm C) 0.1 cm D) 100 μm E) 1,000.000.000 pm 3.1 3.1 2) What structure does light pass through after leaving the condenser in a compound light microscope? A) ocular lens B) objective lens C) specimen D) illuminator 3.2 3.2 3) Which of the following pairs is mismatched? A) nigrosin - negative stain B) methylene blue - simple stain C) acidic dye - capsule stain D) basic dye - negative stain E) crystal violet - simple stain 3.3 Analyzing 8.1 3.7 4) Which of the following places the steps of the Gram stain in the correct order? 1-Alcohol-acetone 2-Crystal violet 3-Safranin 4-Iodine A) 1-2-3-4 B) 2-1-4-3 C) 2-4-1-3 D) 4-3-2-1 E) 1-3-2-4 3.3 8.1 3.9 5) Which of the following pairs is mismatched? A) alcohol-acetone - decolorizer B) crystal violet – basic dye C) safranin – acid dye D) iodine – mordant E) carbolfuchsin – basic dye 3.3 Analyzing 8.1 3.7 6) Which of the following is NOT true regarding the acid-fast stain? A) It is used to identify members of the genus Mycobacterium. B) Acid-fast cells retain the primary dye after treatment with acid-alcohol. C) If cells are acid-fast, they are gram-negative. D) Acid-fast cells appear red in a completed acid-fast stain. E) Non-acid-fast microbes appear blue in a completed acid-fast stain. 3.3 8.1 3.10 7) The purpose of a mordant in the Gram stain is to A) remove the simple stain. B) make the bacterial cells larger. C) make the flagella visible. D) prevent the crystal violet from leaving the cells. E) make gram-negative cells visible. 3.3 8.1 3.10 8) Which of the following places the steps in the correct sequence? 1-Staining 2-Making a smear 3-Fixing A) 1-2-3 B) 3-2-1 C) 2-3-1 D) 1-3-2 E) The order is unimportant. 3.3 8.1 3.8 9) The negative stain is used to A) visualize endospores. B) determine Gram reaction. C) determine flagella arrangement. D) visualize fimbriae. E) determine cell size. 3.3 3.11 10) Simple staining is often necessary to improve contrast in which microscope? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope 3.3 3.8 11) Which microscope is used to see internal structures of cells in a natural state? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope 3.2 3.4 12) Which microscope uses visible light? A) confocal microscope B) differential interference contrast microscope C) fluorescence microscope D) scanning acoustic microscope E) scanning electron microscope 3.2 3.4 13) Which microscope achieves the highest magnification and greatest resolution? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope 3.2 3.5 14) In using this microscope, the observer does NOT look directly at an image through a lens. A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope 3.2 3.5 15) This microscope produces an image of a light cell against a dark background; internal structures are NOT visible. A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope 3.2 3.4 16) A virus measures 100 nm in length. What is its length in μm? A) 10 μm B) 1 μm C) 0.1 μm D) 0.01 μm E) 0.001 μm 3.1 3.1 17) Which of the following is never useful for observing living cells? A) phase-contrast microscope B) darkfield microscope C) scanning acoustic microscope D) scanning electron microscope E) brightfield microscope 3.2 3.5 18) A microorganism measures 5 μm in length. Its length in mm would be A) 500 mm. B) 50 mm. C) 0.5 mm. D) 0.05 mm. E) 0.005 mm. 3.1 3.1 19) Which of the following correctly traces the path of light through the compound microscope? A) light source; condenser; specimen; objective lens; ocular lens B) condenser; light source; specimen; ocular lens; objective lens C) light source; specimen; condenser; objective lens; ocular lens D) condenser; light source; specimen; objective lens; ocular lens E) light source; condenser; objective lens; specimen; ocular lens 3.2 3.2 20) Figure 3.1 In Figure 3.1, line "c" points to the microscope's A) illuminator. B) condenser. C) ocular lens. D) objective lens. 3.2 3.2 21) Which microscope can be used to visualize DNA or botulinum toxin? A) compound light microscope B) phase-contrast microscope C) scanning tunneling microscope D) confocal microscope E) scanning electron microscope 3.2 3.6 22) Which microscope is used to observe a specimen that emits light when illuminated with an ultraviolet light? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope 3.2 3.4 23) Which microscope is most useful for visualizing a biofilm? A) compound light microscope B) phase-contrast microscope C) fluorescence microscope D) scanning acoustic microscope E) transmission electron microscope 3.2 3.6 24) Which microscope takes advantage of differences in the refractive indexes of cell structures? A) compound light microscope B) phase-contrast microscope C) darkfield microscope D) fluorescence microscope E) electron microscope 3.2 3.4 25) You are performing a Gram stain on gram-positive bacteria and you stop after the addition of the first dye. What is the appearance of the bacteria at this point? A) purple B) red C) colorless D) brown 3.3 8.1 3.9 26) You are performing a Gram stain on gram-negative bacteria and you stop after the addition of the mordant. What is the appearance of the bacteria at this point? A) purple B) red C) colorless D) brown 3.3 8.1 3.9 27) You are performing a Gram stain on gram-negative bacteria and you stop after the decolorizer step. What is the appearance of the bacteria at this point? A) purple B) red C) colorless D) brown 3.3 8.1 3.9 28) You are performing a Gram stain on gram-positive bacteria and you stop after the addition of the counterstain. What is the appearance of the bacteria at this point? A) purple B) red C) colorless D) brown 3.3 8.1 3.9 29) Which type of stain is most useful in helping clinicians to decide which antibiotic to prescribe for a bacterial infection? A) negative stain B) simple stain C) Gram stain D) endospore stain E) flagella stain 3.3 Analyzing 3.10 2 30) Which of the following pairs is mismatched? A) confocal microscope - produces a three-dimensional image B) darkfield microscope - uses visible light C) fluorescence microscope - uses a fluorescent light D) scanning electron microscope - produces a three-dimensional image E) scanning tunneling microscope - allows visualization of atoms 3.2 Analyzing 3.4 31) What is the total magnification of a specimen viewed with a 10x ocular lens and a 45x objective lens? A) 4.5x B) 10x C) 45x D) 100x E) 450x 3.2 3.3 32) You are studying a cell structure that is approximately 100 nm in size. Which of the following provides the greatest magnification you can use to see this structure? A) brightfield microscope B) darkfield microscope C) transmission electron microscope D) phase-contrast microscope E) scanning electron microscope 3.2 Analyzing 3.6 2 33) Which microscope uses two beams of light to produce a three-dimensional color image? A) fluorescence microscope B) phase-contrast microscope C) darkfield microscope D) DIC microscope E) electron microscope 3.2 3.4 34) Which microscope is used to see intracellular detail in a living cell? A) fluorescence microscope B) two-photon microscope C) atomic force microscope D) transmission electron microscope E) brightfield microscope 3.2 3.4 35) Which microscope is used to observe viruses and the internal structure of thinly sectioned cells? A) transmission electron microscope B) darkfield microscope C) fluorescence microscope D) brightfield microscope E) scanning electron microscope 3.2 3.6 36) Which microscope is used to see detail of a 300-nm virus? A) fluorescence microscope B) phase-contrast microscope C) darkfield microscope D) DIC microscope E) electron microscope 3.2 3.6 37) Assume you stain Bacillus by malachite green with heat and then counterstaining with safranin. Through the microscope, the green structures are A) cell walls. B) capsules. C) endospores. D) flagella. E) The answer cannot be determined. 3.3 3.11 38) Which step in the Gram stain is the critical step in differentiating gram-positive cells from gram-negative cells? A) safranin B) alcohol-acetone C) iodine D) crystal violet 3.3 Analyzing 8.1 3.9 39) You find colorless areas in cells in a Gram-stained smear. What should you do next? A) an acid-fast stain B) a flagella stain C) a capsule stain D) an endospore stain E) a simple stain 3.3 Analyzing 8.1 3.9 40) Which microscope is best used for observing the surfaces of intact cells and viruses? A) phase-contrast microscope B) darkfield microscope C) fluorescence microscope D) brightfield microscope E) scanning electron microscope 3.2 3.6 41) Bacterial smears are fixed before staining to A) affix the cells to the slide. B) make their walls permeable. C) accept stain. D) make the cells visible. 3.3 8.1 3.8 42) The resolution of a microscope can be improved by changing the A) condenser. B) fine adjustment. C) wavelength of light. D) diaphragm. E) coarse adjustment. 3.2 3.3 43) A student is looking at a bacterial specimen using the oil immersion lens, but has forgotten to put immersion oil on the slide. The specimen will appear A) smaller than it would if immersion oil was used. B) larger than it would if immersion oil was used. C) somewhat fuzzy and have poor resolution. D) the same as it would if the immersion oil was used. E) to have no color. 3.2 8.1 3.3 44) The purpose of the ocular lens is to A) improve resolution. B) magnify the image from the objective lens. C) decrease the refractive index. D) increase the light. E) decrease the light. 3.2 3.3 45) In microscopy, the term resolution A) refers to the ability to distinguish fine structure and detail in a specimen. B) is the same as the total magnification of a specimen. C) is improved when longer wavelengths of light are employed. D) is only observed in stained specimens. E) refers to magnification when using the electron microscope. 3.3 3.3 46) If a patient had a bacterial infection that was not syphilis but was tested for syphilis using the FTA-ABS test, what would the technician observe? A) fluorescent cells on a dark background. B) no fluorescence in the patient sample. C) fluorescence of a different color than expected. D) three-dimensional host tissue cells with organelles clearly visible. E) brightly colored three-dimensional bacterial cells. 3.3 3.4 47) An acidic dye A) has a positively charged chromophore. B) has a negatively charged chromophore. C) is used to stain the background in a negative stain. D) is used to stain nuclei. E) has a negatively charged chromophore and is used to stain the background in a negative stain. 3.3 8.1 3.7 48) Immersion oil is necessary when using the 100x objective on a compound light microscope A) to lubricate the objective. B) to prevent the slide from scratching the lens. C) otherwise the image will be fuzzy. D) otherwise too much light is lost to refraction. E) otherwise too much light is lost to refraction and the image will be fuzzy. 3.2 8.1 3.2 49) Which demonstrates better resolution? A) measuring two bacteria arranged end to end as individually having a length of 2μm B) measuring two yeast cells as individually having a diameter of 10μm C) observing two adjacent bacteria as individually having a width of 0.3μm D) observing a clump of algae 0.5mm by 0.75 mm E) measuring a flea as mm at the longest point 3.2 8.1 3.3 50) Which two staining techniques employ a mordant? A) Gram stain; Flagella stain. B) Gram stain; Acid-fast stain. C) Simple stain; Acid-fast stain. D) Capsule stain; Flagella stain. E) Gram stain; Capsule stain. 3.3 8.1 3.10 3.2 True/False Questions 1) The counterstain used in the Gram stain is a basic dye. 3.3 8.1 3.7 2) In a completed Gram stain, gram-negative bacteria are colorless. 3.3 8.1 3.9 3) In a completed Gram stain, gram-positive bacteria are purple. 3.3 8.1 3.9 4) If acid-fast bacteria are stained with the Gram stain, they will stain gram-negative. 3.2 3.10 5) The limit of resolution of the compound microscope illuminated with visible light is approximately 0.2 μm. 3.2 3.3 6) Both phase-contrast microscopy and differential interference contrast microscopy are used to view the internal structures of cells without staining. 3.2 3.4 7) Cells viewed in darkfield microscopy appear similar to those stained with the negative stain. 3.3 3.4 8) The capsules and flagella of bacteria can be observed in gram-stained smears. 3.3 3.11 9) The greater resolution of the electron microscope compared to the compound microscope is due to the longer wavelengths of the electrons used to examine specimens. 3.2 3.5 10) Scanned probe microscopy is used to examine fine detail of molecular complexes, such as blood clots, or molecules, such as DNA. 3.2 3.6 3.3 Essay Questions 1) In 1877, Robert Koch thought preparing permanently stained slides would be valuable. Why was his assessment correct? 3.3 3.8 2 2) In 1884, Hans Christian Gram described a method of staining bacterial cells while not staining surrounding animal tissues. However, he thought that the staining method he developed was faulty because not all bacteria stained. In a letter to the editor of the journal in which Gram published his findings, write your response to Gram's concern. 3.3 3.10 2 3) You are working in a clinical laboratory and you need to examine an unstained urine sample for the presence of bacteria. What type of light microscope should you use to observe this specimen? Explain your answer. 3.2 3.4 2 4) Compare and contrast the Gram stain and the acid-fast stain. 3.3 8.1 3.10 8 5) How are brightfield, darkfield, phase-contrast and fluorescence microscopy similar? 3.2 8.1 3.4 8 Microbiology: An Introduction, 13e (Tortora et al.) Chapter 4 Functional Anatomy of Prokaryotic and Eukaryotic 4.1 Multiple-Choice Questions 1) Which of the following statements is INCORRECT regarding prokaryotic cells? A) Their DNA is not enclosed within a membrane. B) They lack membrane-enclosed organelles. C) They typically have a circular chromosome. D) They reproduce by binary fission. E) They lack a plasma membrane. 4.1 2.2 4.1 2) Each of the following statements concerning the gram-positive cell wall is true EXCEPT A) it maintains the shape of the cell. B) it is sensitive to lysozyme. C) it protects the cell in a hypertonic environment. D) it contains teichoic acids. E) it is sensitive to penicillin. Analyzing 2.2 4.5 2 3) Which of the following statements best describes what happens when a bacterial cell is placed in a solution containing 5% NaCl? A) Sucrose will move into the cell from a higher to a lower concentration. B) The cell will undergo osmotic lysis. C) Water will move out of the cell. D) Water will move into the cell. E) No change will result; the solution is isotonic. 4.5 4.9 2 4) A gram-positive bacterium suddenly acquires resistance to the antibiotic methicillin. This trait most likely occurred due to acquisition of new genetic information through A) conjugation. B) binary fission. C) meiosis. D) transformation. E) transduction. 4.3 4.1 2 5) By which of the following mechanisms can a cell transport a substance from a lower to a higher concentration? A) simple diffusion B) facilitated diffusion C) active transport D) extracellular enzymes E) aquaporins 4.5 Analyzing 4.9 2 6) Which of the following is NOT a typical characteristic of most bacterial plasma membranes? A) site of energy production B) composed of a phospholipid bilayer C) contains proteins D) contains cholesterol E) is selectively permeable 4.5 2.4 4.8 2 7) Which one of the following organisms has a cell wall? A) protoplasts B) fungi C) L forms D) mycoplasmas E) animal cells 4.7 2.4 4.14 7 8) Which of the following statements is TRUE? A) Endospores are for reproduction. B) Endospores allow a cell to survive environmental changes by producing a dormant period with no growth. C) Endospores are easily stained in a Gram stain. D) A cell produces one endospore and keeps growing. E) A cell can produce many endospores. 4.5 4.12 9) Which of the following pairs is mismatched? A) endoplasmic reticulum – internal transport B) Golgi complex – secretion C) mitochondria – ATP production D) centrosome – food storage E) lysosome – digestive enzymes 4.11 4.19 10) Which of the following organelles most closely resembles a prokaryotic cell? A) nucleus B) mitochondrion C) Golgi complex D) vacuole E) cell wall 4.11 4.19 7 Figure 4.1 11) Which drawing in Figure 4.1 is a tetrad? A) a B) b C) c D) d E) e 4.2 4.2 12) Which drawing in Figure 4.1 possesses an axial filament? A) a B) b C) c D) d E) e 4.2 4.2 13) Which drawing in Figure 4.1 is streptococci? A) a B) b C) c D) d E) e 4.2 4.2 14) Antibiotics that target cell wall synthesis ultimately cause bacterial cell death as a result of A) osmotic lysis. B) inhibition of molecular transport. C) decreased synthesis of plasma membrane. D) plasmolysis. E) cell shrinkage. 4.5 3.4 4.9 2 15) Bacteria are a commonly used organism for studies of genetic material in the research laboratory. The nucleic acids must first be isolated from the cells for these studies. Which of the following would most likely be used to remove the cell wall from gram-positive bacterial cells prior to their lysis for nucleic acid isolation? A) lysozyme B) polymixins C) alcohol D) water E) mycolic acid 8.5 4.5 16) Which of the following statements about gram-negative cell walls is FALSE? A) They protect the cell in a hypotonic environment. B) They have an extra outer layer composed of lipoproteins, lipopolysaccharides, and phospholipids. C) They are toxic to humans. D) They are sensitive to penicillin. E) Their Gram reaction is due to the outer membrane. Analyzing 2.2 4.5 2 17) Which of the following structures is NOT found in some prokaryotic cells? A) flagellum B) axial filament C) cilium D) pilus E) peritrichous flagella 4.6 2.4 4.13 2 18) Functions of the glycocalyx include all of the following EXCEPT A) biofilm formation. B) increased virulence. C) source of nutrition. D) protection against dehydration. E) binary fission. 4.3 4.3 2 19) Which structure protects bacteria from being phagocytized? A) slime layer B) fimbriae C) capsule D) cell membrane E) cell wall 4.3 2.2 4.3 2 20) Which of the following is NOT part of the passive transport process? A) plasma membrane B) transporter proteins C) ATP D) concentration gradient E) aquaporins 4.5 Analyzing 4.9 2 21) Figure 4.2 Which of the following terms best describes the cell in Figure 4.2? A) peritrichous flagella B) amphitrichous flagella C) lophotrichous flagella D) monotrichous flagellum E) axial filament 4.3 3 22) In bacteria, photosynthetic pigments are found in A) chloroplasts. B) cytoplasm. C) chromatophores. D) mesosomes. E) ribosomes. 4.5 4.11 2 23) The difference between simple diffusion and facilitated diffusion is that facilitated diffusion A) moves materials from a higher to a lower concentration. B) moves materials from a lower to a higher concentration. C) requires ATP. D) requires transporter proteins. E) does not require ATP. 4.5 Analyzing 4.9 7 24) The terms "run" and "tumble" are generally associated with A) cell wall fluidity. B) taxic movements of the cell in response to attractants or repellents. C) clustering properties of certain rod-shaped bacteria. D) cell membrane synthesis. 4.3 2 25) You have isolated a motile, gram-positive cell with no visible nucleus. You can safely assume that the cell A) has 9 pairs + 2 flagella. B) has a mitochondrion. C) has a cell wall. D) lives in an extreme environment. E) has cilia. 2.2 4.5 2 26) Fimbriae and pili differ in that A) there are only one or two pili per cell. B) pili are used for motility. C) pili are used to transfer DNA. D) pili are used for transfer of DNA and motility. E) pili are used for attachment to surfaces. 4.3 2 Figure 4.3 27) In Figure 4.3, which diagram of a cell wall is a gram-negative cell wall? A) a B) b C) both a and b D) neither a nor b E) The answer cannot be determined based on the information provided. Analyzing 4.5 3 28) In Figure 4.3, which diagram of a cell wall possesses lipid A/endotoxin responsible for symptoms associated with infection? A) a B) b C) both a and b D) neither a nor b E) The answer cannot be determined based on the information provided. Analyzing 4.5 3 29) In Figure 4.3, which diagram of a cell wall has a structure that protects against osmotic lysis? A) a B) b C) both a and b D) neither a nor b E) The answer cannot be determined based on the information provided. Analyzing 4.5 3 30) In Figure 4.3, which diagram of a cell wall is decolorized by a brief exposure to alcohol? A) a B) b C) both a and b D) neither a nor b E) The answer cannot be determined based on the information provided. Analyzing 8.1 4.5 3 31) In Figure 4.3, which diagram of a cell wall is resistant to many antibiotics (e.g., penicillin)? A) a B) b C) both a and b D) neither a nor b E) The answer cannot be determined based on the information provided. Analyzing 2.2 4.5 3 32) In Figure 4.3, which diagram of a cell wall contains teichoic acids? A) a B) b C) both a and b D) neither a nor b E) The answer cannot be determined based on the information provided. Analyzing 4.5 3 33) In Figure 4.3, which diagram of a cell wall contains porins? A) a B) b C) both a and b D) neither a nor b E) The answer cannot be determined based on the information provided. Analyzing 4.5 3 34) Where are phospholipids most likely found in a prokaryotic cell? A) flagella B) organelles C) the plasma membrane D) ribosomes E) the plasma membrane and organelles 4.5 4.8 2 35) Where are phospholipids most likely found in a eukaryotic cell? A) metachromatic granules B) organelles C) the plasma membrane D) ribosomes E) the plasma membrane and organelles 4.5 2.4 4.8 2 36) Which of the following is NOT found or observed to occur in both mitochondria and prokaryotes? A) circular chromosome B) 70S ribosomes C) cell wall D) binary fission E) ATP-generating mechanism 4.11 Analyzing 2.4 4.19 7 37) Which of the following statements is correct about passive diffusion? A) It requires an expenditure of energy by the cell. B) It is a process in which molecules move from a region of higher concentration to a region of lower concentration (or down a concentration gradient). C) It is a process in which molecules move from a region of lower concentration to one of higher concentration (or up a concentration gradient). D) It may require a transport protein. E) It involves movement of molecules down a concentration gradient and may require a transport protein. 4.5 4.9 7 38) Oxygen crosses a plasma membrane A) by osmosis. B) through simple diffusion. C) with the help of a nonspecific transporter. D) through facilitated diffusion. E) through porins. 4.5 4.9 2 39) In a hypertonic solution, a bacterial cell will typically A) lyse. B) burst. C) stay the same. D) plasmolyze. E) osmolyze. 4.5 4.9 2 40) What will happen if a bacterial cell is pretreated with a lysozyme solution, then placed in distilled water? A) The cell will plasmolyze. B) The cell will undergo osmotic lysis. C) Water will leave the cell. D) Lysozyme will diffuse into the cell. E) No change will result; the solution is isotonic. 4.5 Analyzing 4.9 2 41) How do spirochetes and spirilla differ? A) Spirochetes do not have a cell wall but spirilla do. B) Spirilla are found in chains of cells whereas spirochetes exist as individual cells. C) Spirilla have external flagella but spirochetes have axial filaments. D) Spirochetes have a rigid, corkscrew shape while spirilla are helical and more flexible. E) Spirochetes and spirilla are basically the same organisms and the terms can be used interchangeably. 4.3 Analyzing 2 42) Which one of the following pairs is mismatched? A) metachromatic granules - phosphate storage B) lipid inclusions - energy reserve C) ribosomes - carbon storage D) sulfur granules - energy reserve E) gas vacuoles - flotation 4.5 Analyzing 4.10 7 43) Which of the following are NOT energy reserves? A) carboxysomes B) polysaccharide granules C) lipid inclusions D) ribosomes E) metachromatic granules 4.5 4.11 7 44) Which of the following is NOT a functionally analogous pair? A) nucleus -nucleoid region B) mitochondria - prokaryotic plasma membrane C) chloroplasts - thylakoids D) cilia - pili E) 9+2 flagella - bacterial flagella 4.6 2.4 4.13 2 45) The DNA found in most bacterial cells A) is surrounded by a nuclear membrane. B) utilizes histones for chromosomal packaging. C) is circular in structure. D) is linear in structure. E) is found in multiple copies. 4.5 4.10 2 46) Cells may frequently find themselves in an environment with very low extracellular concentrations of substances needed in higher amounts inside the cell. To obtain these needed items, such cells would be most likely to engage in A) simple diffusion. B) facilitated diffusion. C) active transport. D) osmosis. 4.5 4.9 47) What is the best reason why oxygen (O2) can cross the plasma membrane by simple diffusion, but glucose must be transported across the barrier by facilitated diffusion? A) Oxygen is a much smaller molecule, making it easier to pass through the molecules of the plasma membrane. B) Oxygen is a nonpolar molecule, easily passing through the nonpolar middle area of the plasma membrane. C) Oxygen can be burned/consumed as it crosses the membrane, providing the energy needed for its passage. D) Glucose is nonpolar, making it very difficult for it to cross the polar portions of the plasma membrane structure. 4.5 4.9 48) In bacterial ribosomes, a small 30S subunit and a large 50S subunit come together to produce the functional 70S ribosome. Why isn't it an 80S ribosome? A) The ribosome will become an 80S complex when the protein it is producing starts to be formed. B) Additional factors are required for protein synthesis. When these are put with the ribosome, it will become an 80S ribosome complex. C) S stands for Svedberg units, which indicates the relative rate of sedimentation due to size, weight, and shape of a particle. The numbers aren't strictly additive. D) A portion of the larger 50S subunit is detached as the ribosomes come together, making the final complex a 70S ribosome instead of an 80S ribosome. 4.5 4.10 49) A particular type of inclusion body that is used to orient bacteria in three-dimensional space in a fluid environment is the A) gas vacuole. B) carboxysome. C) sulfur granule. D) metachromatic granule. 4.5 4.11 50) Endospores are highly resistant to harsh environmental conditions due to all EXCEPT which one of the following? A) dipicolinic acid (DPA) in the endospore B) very low amounts of water C) high concentration of calcium ions D) a thick spore coat E) small triggering molecules called germinants 4.5 4.12 4.2 True/False Questions 1) The cell walls of bacteria are responsible for the shape of the bacteria and the difference in the Gram stain reaction. 4.2 Analyzing 4.2 2 2) Antibiotics that target the cell wall are an effective treatment against many pathogenic bacteria. Analyzing 2.2 4.5 7 3) Cells placed in a hypertonic solution tend to lose water due to osmotic pressure. 4.5 Analyzing 4.9 2 4) Small, hydrophobic molecules pass through a cell membrane most easily by simple diffusion. 4.5 4.9 2 5) Spheroplasts, protoplasts, and mycoplasms are bacterial cells without cell walls. 4.7 6) Endospores are a reproductive structure. 4.5 4.12 2 7) The internal structure of bacterial and eukaryotic flagella are the same. 4.6 4.13 7 8) Many enzymes in both prokaryotic and eukaryotic cells are compartmentalized within organelles. 4.11 2.4 4.18 7 9) Prokaryotes lack organelles. 4.1 4.1 2 10) If you observe rod-shaped red cells after the Gram stain, you can assume their cell walls contain endotoxin. Analyzing 4.5 2 4.3 Essay Questions 1) Compare and contrast the characteristics of a typical prokaryotic and eukaryotic cell. 4.11 2.4 4.18 8 2) Provide evidence to substantiate the hypothesis that eukaryotic cells evolved from prokaryotic cells. 4.12 4.20 8 3) Compare and contrast gram-positive and gram-negative cell walls with regard to (a) sensitivity to antimicrobial agents, (b) resistance to phagocytosis, (c) chemical composition, and (d) decolorization by alcohol. 2.2 4.5 8 4) What is a biofilm and what role does biofilm play in disease? 4.3 5.2 4.3 8 5) Based on the description of typical cell structures depicted in this chapter, do you think it is possible for microbial life on Mars to exist? Remember, the environment on Mars is very cold, and there is no appreciable free-flowing water. The core appears to be at least partially molten. Gravity is less than that on Earth, and solar radiation levels are higher. The atmosphere is roughly 95% carbon dioxide and much less than 1% oxygen. If life COULD exist, what might it look like, and why? 4.11 Creating 4.19 Microbiology: An Introduction, 13e (Tortora et al.) Chapter 5 Microbial Metabolism 5.1 Multiple-Choice Questions 1) Which of the following compounds is NOT an enzyme? A) dehydrogenase B) cellulase C) coenzyme A D) β-galactosidase E) sucrase 5.2 5.3 2) Figure 5.1 Which compound is being reduced in the reaction shown in Figure 5.1? A) isocitric acid and α-ketoglutaric acid B) α-ketoglutaric acid and NAD+ C) NAD+ D) NADH E) NADH and isocitric acid 5.3 5.8 3 3) Which organism is NOT correctly matched to its energy source? A) photoheterotroph - light B) photoautotroph - CO2 C) chemoautotroph - Fe2+ D) chemoheterotroph - glucose E) chemoautotroph - NH3 5.9 Analyzing 3.1 5.23 2 4) Which of the following statements about anaerobic respiration is FALSE? A) It yields lower amounts of ATP when compared to aerobic respiration. B) The complete Krebs cycle is utilized. C) It involves the reduction of an organic final electron acceptor. D) It generates ATP. E) It requires cytochromes. 3.1 5.15 5) Figure 5.2 What type of reaction is in Figure 5.2? A) decarboxylation B) transamination C) dehydrogenation D) oxidation E) reduction 5.10 Analyzing 5.24 2 6) What is the fate of pyruvic acid in an organism that uses aerobic respiration? A) It is reduced to lactic acid. B) It reacts with oxaloacetate to form citrate. C) It is oxidized in the electron transport chain. D) It is catabolized in glycolysis. E) It is converted into acetyl CoA. 5.15 7) Figure 5.3 How would a noncompetitive inhibitor interfere with a reaction involving the enzyme shown in Figure 5.3? A) It would bind to a. B) It would bind to b. C) It would bind to c. D) It would bind to d. E) The answer cannot be determined based on the information provided. 5.2 5.6 8) Figure How is ATP generated in the reaction shown in Figure ? A) glycolysis B) fermentation C) photophosphorylation D) oxidative phosphorylation E) substrate-level phosphorylation 5.3 5.9 2 9) Fatty acids are oxidized in A) the Krebs cycle. ........................CONTINUED.................................................