Micro Final Study Guide
244. The smallest genomes belong to parasitic microbes. Select characteristics that apply to the genome of parasitic microbes a. Have lost genes that encode products that are involved in many metabolic functions b. Lack noncoding sequences found in eukaryotes c. Possess less open reading frames d. Depend on the host for many metabolic functions
A,B,D
263. Superantigens are processed by antigen presenting cells a. True b. False
B
274. This microorganism is typically an extracellular pathogen a. Histoplasma b. Chlamydia c. Aspergilllus d. Influenza
C
190. Select all of the differences between DNA and RNA to test your understanding of these nucleic acids a. DNA is double stranded, RNA is single stranded b. DNA nucleotides contain deoxyribose whereas RNA nucleotides contain ribose c. DNA contains the following nitrogenous bases: A,C,G and U and RNA contains A,C,G and T d. There are multiple types of DNA with different functions whereas there is only one type of RNA
a,b
119. Who of the following was the first to observe and accurately describe microorganisms? a. Pasteur b. van Leeuwenhoek c. Lister d. Tyndall
b
139. One DNA strand is used as the template to make two new strands of DNA. a. True b. False
b
121. This question may have more than 1 correct answers. Refer to Fig. 4. This image was produced by Transmission Electron Microscopy (TEM) and colorized by a graphic artist with yellows, reds, blues and greens to emphasize the different elements. To set up this experiment, it is likely that the investigator cultured E. coli bacteria and inoculated them with a stab from a plaque that came from a separate agar plate spread with E. coli. What is likely to be happening in this image? a. a plaque from a prion disease has formed on the surface of a cell b. A dsDNA virus is positioned to inject its genome through the cell envelope of the E. coli c. The redish orange object in the center of the image is a T4 phage d. an ABC permease system is moving a packet of molecules across the membrane e. None of these options
b,c
127. What is correct about the major plasma membrane phospholipid in bacteria? (Mark all that apply) a. three fatty acid chains are linked to one glycerol group b. ethanolamine is at the polar, hydrophilic end c. a phosphate group connects the glycerol to the ethanolamine d. the phospholipid is an amphipathic molecule e. none of these options
b,c,d
131. Viruses can either cause cancer or trigger events that lead to cancer by what mechanisms? (Mark all that apply) a. mutation of a viral coat protein to change its tropism b. insertion of an oncogene into the host cell c. inactivation of a host tumor suppressor gene d. activation of a host protooncogene e. None of these options
b,c,d
132. Which of the following provides evidence in support of the primary role of RNA in the evolution of life: (Mark all that apply) a. RNA is less chemically stable than DNA b. Some RNA molecules are catalytic c. RNA catalyzes peptide bond formation during protein synthesis d. ATP (energy source in the cell) is a ribonucleotide e. RNA can regulate gene expression
b,c,d,e
166. Select all that apply to the fueling reactions performed by microorganisms a. Nucleic acids b. Results in the production of reducing power c. Synthesis od macromolecules for cellular use d. Precursor metabolites are produced during pathways e. Molecules that serve as a ready supply of electrons for a variety of chemical reactions f. ADP g. ATP h. The primary molecule used to conserve the energy supplied by an energy source i. Production of small molecules that provide the carbon skeletons needed for biosynthesis
b,d,e,g,h,i
26. During bacterial cytokinesis, a critical step in septation is the assembly of the __________. a. replisome. b. spindle body. c. Z ring. d. cytoskeletal spiral
c.
133. A new protein has been described that transports a growth factor across the plasma membrane. This protein is most likely a/an: a. cytoplasmic protein. b. peripheral membrane protein, facing outward. c. peripheral membrane protein, facing the cytoplasmic side. d. integral membrane protein
d
135. Which molecule is believed to have preceded the other three during the evolution of life? a. Glycolipids b. DNA c. Proteins d. RNA
d
155. In feedback inhibition, the inhibitor of the biochemical pathway is typically a. The substrate of the enzyme inhibited b. The product of the enzyme inhibited c. A substance that is produce towards the middle of the biochemical pathway d. The final product of the biochemical pathway e. A product of another biochemical pathway
d
188. If 35S was found in progeny phages rather than 32P, Hershey and Chase would have concluded that a. Proteins contain phosphorus b. DNA contains sulfur c. Phage DNA enters the host cell d. Phage protein enters the host cell e. Phage can kill the E.coli cell
d
193. Identify any item needed for the replication of the lagging strand of DNA a. Okazaki fragments b. Primase c. DNA ligase d. All of the above
d
194. What enzyme synthesizes the daughter strands during DNA replication? a. DNA primase b. Helicase c. RNA polymerase d. DNA polymerase e. Topoisomerase
d
276. Pathogens produce virulene factors primarily to a. Maintain temperature and pH values b. Cause disease c. Change its environment d. Outcompete host cells for resources
d. Outcompete host cells for resources
144. Some outbreaks of Salmonella have been linked to chocolate consumption. As the processing of cocoa beans requires heating steps, it was assumed that Salmonella contaminants would be killed during processing. Calculating the D values of Salmonella at 70C gave these data: glucose solution 0.03, milk 0.35, milk chocolate 813. Which of the following can be validity concluded from these data? a. Temperatures lower then 70C should be used b. Milk chocolate should not be consumes with compromised immune system c. Milk is not the source of Salmonella in milk chocolate related outbreaks d. Components of milk chocolate exert protective effects on Salmonella cells
?
220. Some degradative pathways are regulated by an activator protein. AN activator protein is a regulatory protein that facilitated transcription to DNA a. True b. False
A
221. ____ mutations arise occasionally in all cells and in the absence of any added agent a. Spontaneous b. Induced c. Planned d. Triggered
A
224. When DNA is damaged by UV light and not repaired a. Neither DNA replication not transcription can occur and the organism will probably die b. The damaged part will be excised and allow DNA replication to proceed c. DNA replication can proceed as normal but transcription is prevented d. Transcription can proceed as normal but replication is prevented
A
227. In dark repair, the final phosphodiester bond is formed by DNA ligase a. True b. False
A
228. After a tautomeric shift in adenine a. Adenine bonds with cytosine b. Adenine bonds with uracil c. Adenine is unable to bond with any molecule d. Adenine bonds with thymine
A
231. DNA mutations are passed on to a cells progeny a. True b. False
A
235. Sticky ends are a. Single stranded DNA sequences that are generated by staggered ends b. Double stranded DNA sequences that are generated by staggered cuts c. Single stranded DNA sequences that are generated by blunt ends d. Double stranded DNA sequences that are generated by blunt ends
A
237. What is needed in order to carry out real time PCR to determine the amount of a specific DNA sequence in a sample? a. Taq polymerase b. Thermocycler c. Fluorescence reporter d. Ligase e. Restriction enzymes
A
241. The joining of sticky ends involves the formation of phosphodiester bonds a. True b. False
A
243. To determine if a suspect was present at a scene, a crime scene investigator gathers a small biological sample collected at a murder scene. Which type of PCR would be best to use for this task? a. End point PCR b. Either end point or real time c. Real time PCR d. Not enough info
A
246. Alignment of nucleotides on the same genome may show that the nucleotide sequences of two or more genes are so alike that the probably arose through gene duplication and are called a. Paralogues b. Orthologues c. Open reading frames d. Conserved hypothetical genes
A
256. Complement factor C3b coats a bacterium and binds to C3b receptors on phagocytes, making the bacterium more susceptible to being phagocytized a. True b. False
A
257. A phagosome containing the engulfed bacteria combines with a lysosome containing enzymes to produce a phagolysosome a. True b. False
A
260. Which of the following statements is correct about innate and adaptive immunity? a. When reexposed to the same pathogen or substance, the adaptive immune response of the host reacts so quickly that there is usually no noticeable illness b. Innate immunity is highly selective in that it ca be directed against one pathogen or foreign substance c. The innate immune system is able to generate an enormous diversity of molecules such as cellular receptors and soluble proteins, including antibodies that recognize trillions of different foreign substances d. The innate immune system almost always responds selectively to nonself and produces responses tailored to protecting that type of stimulus
A
261. Superantigens are produced by _____ a. Staphylococcus auereus in toxic shock syndrome b. E.coli in toxic shosck syndrome c. Cells infected with specific viruses d. Superantibodies
A
267. Helper T cells can interact with target cells by recognizing antigens that are complexed with MHC proteins a. True b. False
A
272. Initial attachment of mircoorganisms often involves a. Flagella and is reversible b. Flagella and is irreversible c. Exopolymers and is reversible d. Either flagella or exoploymers and is irreversible
A
269. Choose those that correctly apply to antibody diversity a. Class switching from IgM to IgG occurs only after a B cell has encountered its corresponding antigen b. The V and J regions can be joined in a variety of differential ways due to splice site variability at the junction c. Combinatorial joining occurs in germ line DNA, therefore once the gene has been spliced, the B cell can only make one variable region for all antibodies produced d. The V regions of germ line B cell DNA contain fragments that are susceptible to hypermutation, error prone DNA repair enhances sequence diversity even further
A,B,C,D
252. The complement system acts in a cascading fashion to ____ a. Enhance phagocytosis b. Lyse cell membranes of target cells c. Stimulate antibody production d. Assist in memory cell development
A,B,D
214. Select all of the following characteristics that apply to a helix turn helix DNA binding domain a. This DNA binding domain recognizes and binds to palindromic sequences b. This DNA binding domain if often found in eukaryotic regulatory proteins c. This DNA binding domain is found in the lac repressor d. This DNA binding domain is stabilized by the interaction of amino acids with zinc ion e. The regulatory protein forms a dimer, with each component interacting with a major groove of the DNA f. This DNA binding domain is found in the trp repressor
A,B,F
245. Select the characteristic that apply to metagenomic libraries that can be prepared from DNA extracted from environmental samples a. Can be used for screening nucleotides for a specific function b. Require the construction of a DNA library c. Can be used for determining phylotypes d. Introduce clong efficiency bias
A,C
270. Which of the following organisms contain a pathogenicity island that encodes for type 3 secretion proteins? a. Yersinia pestis b. Helicobacter pylori c. Vibrio cholerae d. Shigella flexneri
A,C,D
218. Transcription is turned off by a. Induction b. Repression c. Activation d. Induction, repression and activation
B
222. Since exposure to antibiotics is a selective force for maintaining resistance genes in a population, increasing antibiotic use will reduce overall resistance a. True b. False
B
223. UV light damages DNA by causing covalent bonds to form between a. Two thymine nucleotides on opposing DNA strands b. Thymine nucleotides next to each other in the same DNA strand c. A thymine and an adenine on the same DNA strand d. Two cytosines net to each other on the same DNA strand
B
226. Excision repair takes place only in the presence of light a. True b. False
B
232. When thymine dimers form, they weaken a. Covalent bonds b. Hydrogen bonds c. Sulfide bonds d. Ionic bonds
B
236. Restriction enzymes cut DNA at random sites a. True b. False
B
239. The single stranded ends of DNA molecules can be joined together by a. Restriction endonucleases b. DNA ligase c. DNA polymerase d. Primase e. Helicase
B
242. Restriction enzymes cut only at specific sites and therefore are not useful for genetic engineering a. True b. False
B
248. When Alexander Fleming discovered what was to become penicillin, he noticed that wherever mold was growing on plates of Staphylococus there was a zone of inhibitpn pf bacterial growth around the fungi. What type of symbiotic relationship does this describe? a. Cooperative b. Ammensalistic c. Commensalistic d. Mutualistic
B
254. Phagocytes are attracted to all of the following except a. Phospholipids released by injured cells b. Lysosomes c. Components of the complement system d. Chemical products of microorganisms
B
255. In phagocytosis, the digested contents are eliminated by a. Endocytosis b. Exocytosis c. Opsonization d. C3b
B
258. Both neutrophils and macrophages are active phagocytic cells. When comparing tissue distribution for these two cells types, neutrophils predominantly take up residence in specific tissues once they mature, whereas macrophages remain in the blood until they are stimulated to migrate a. True b. False
B
265. B cell differentiation is stimulated by a. Lipids b. Interleukins c. Antibodies d. Interferons
B
266. Each B cell can react to many different types of antigens a. True b. False
B
268. There are as many genes in the germ line DNA as there are types of antibodies a. True b. False
B
275. Virulence is the potential for an organism to cause disease, whereas pathogenicity refers to the degree of harm caused by the organism a. True b. False
B
46. Which answer best explains why antibiotics targeting the cell wall of bacteria have few side effects on people? a. The human anatomy prevents antibiotics from entering their cells. b. Peptidoglycan is a compound that is unique to bacteria and those antibiotics targeting bacterial cell walls are unlikely to target any compounds that people have in or on their cells. c. Antibiotics are synthesized by bacteria to kill other microbes and therefore do not harm people. d. Antibiotics are so quickly metabolized by human cells that they don't have a chance to bind to the antibiotic targets (or causes so little damage that it is inconsequential).
B
219. In regulation by repression a. A sugar, such as lactose, acts as an inducer and combines with the repressor to prevent transcription b. AN induce activates the activator so that it binds to DNA and prevents transcription c. An amino acid activates the repressor so that the repressor binds to the operator and prevents transcription d. An amino acid bind to the operator, blocking the repressor, allowing transcription to proceed
C
225. In light repair a. The damaged segment of DNA is excised by DNA polymerase b. A single thymine is excised c. The covalent bonds between the thymine dimers are broken d. The damaged segment of DA is excised by DNA ligase
C
230. In a tautomeric shift a. Carbon atoms move to form a base with altered properties b. Final bonding of nucleotides remains unchanged c. Hydrogen atoms move to form a base with altered hydrogen properties d. It is always adenine that is changed e. Adenine is changed so it can no longer form base pairs
C
234. The function of the enzyme ligase is to a. Add new DNA to the plasmid b. Remove DNA from the plasmid c. Form covalent bonds between cloned gene and plasmid d. Repair damaged DNA e. Purify the plasmid DNA
C
240. To copy a human DNA sequence to be placed into a bacterialplasmid DNA, human DNA must be cut with restriction enzyme A then it can be joined to a. Human DNA cut with restriction enzyme B b. Human DNA that is uncut c. Bacterial DNA cut with restriction enzyme A d. Bacterial DNA that is uncut e. None of the above
C
247. The relationship between the bacterium X. nematophilia and its nematode host, S. carpocapsea, is classified as cooperation because both organisms benefit and a. X lives in the gut of S b. X lives in the gut of S and on the insects home c. X and S can be grown separately d. X protects the home of S
C
249. Rice seedling blight is a plant disease cause by the fungus R. microspores that harbos intracellular bacteria in the genus Burkholderria. A toxin produced in B bacteria kills the seeds, the fungus then consumes the poisoned seeds. In the lab R and B bacteria can be grown in pure culture Which of the following pairs of words best describe this microbial symbiosis? a. Endosymbont, mutualism b. Ectosymbiont, commesalism c. Endosymbiont, cooperation d. Ectosymbiont, ammensalism
C
250. You have isolated a soil protozoan, which you are now trying to grow in pure culture, You have tried many different types of media but you can find growth only if bacteria are also present. You note that the bacterial population declines as the protozoan population increases. Which of the following symbiotic relationships is this? a. Commensalistic b. Mutualistic c. Predation d. Ammensalistic
C
251. You decide to study the microbiome of a species of spider that is locally abundant. You are able to cultivate many bacteria from the gut, and the spiders do not appear to be negatively affected by treatment with antibiotics that you know will inhibit the growth of these bacteria. This relationship is a. Cooperative b. Mutualistic c. Commensalistic d. Ammensalistic
C
264. Arrange the following in the proper order in which they occur during clonal selection. 1) helper T cells are activated, 2) macrophages ingest antigen, 3) B cells differentiate into plasma cells and memory cells a. 3,2,1 b. 2,3,1 c. 2,1,3 d. 3,2,1 e. 1,2,3
C
229. A mutation that causes a change in a single nucleotide in DNA a. Will have no effect b. Causes codon to be correct, but the anticodon to be incorrect c. Cause protein synthesis to stop d. Changes corresponding nucleotide in mRNA, resulting in different codon
D
233. Arrange the flowing events in the proper sequence for gene cloning. 1) incorporate gene into bacterial plasmid, 2) isolate DNA from organism containing desired gene, 3) incorporate cloned gene into bacterial cells, 4) fragment DNA with restriction enzyme a. 1,2,3,4 b. 2,1,4,3 c. 2,3,4,1 d. 2,4,1,3 e. 2,4,3,1
D
238. What DNA base sequence could NOT be the recognition site of a restriction endonuclease? a. GAATTCC, CTTAAG b. ATCGAT, TAGCTA c. CTGCAG, GACGTC d. GCTTGC, CGAACG
D
253. A person unable to make lysozyme in their tears will be susceptible to infection by a. Viruses b. Fungi c. Gram negative bacteria d. Gram positive bacteria
D
259. Little Suzie has antibodies that bind specifically to the virus that causes mumps. What scenario have provided her with the antibodies? a. Suzie's mother's antibodies crossed the placenta during gestation b. Suzie has a clone of plasma cells making antibodies in anticipation of getting the disease c. Suzie developed mumps, recovered, and now has a population of B memory cells d. Suzie was vaccinated against mumps as an infant
D
273. Which of the folling gradients can form in a biofilm? a. Oxygen gradient b. Nutrient gradient c. pH gradient d. All of the above
D
262. Possible symptoms of toxic shock syndrome include a. Fever b. Diarrhea c. Naseua and vomiting d. Shock e. All of the above
E
271. On which of the following surfaces can biofilms form? a. Animal biotic surfaces b. Plant biotic surfaces c. Abiotic surfaces d. Animal and pant biotic surfaces e. Biotic or abiotic surfaces
E
107. Which of the following enzymes or RNA molecules is NOT part of the replisome for bacterial chromosomal replication? a. Resolvase b. Helicase c. DNA Primase d. DNA polymerase III e. DNA topoisomerase
a
108. While examining the sequence of nucleotides in the replicon region of bacterial DNA, you note an abundance of adenine and thymine base pairs. This leads you to conclude that this particular section of the DNA must be the a. oriC site. b. Pribnow box. c. Shine Delgarno sequence. d. ter site.
a
112. How is mismatch repair accomplished by the E. coli proteins at sites where a mismatched basepair remains if the replicative DNA polymerase proofreading fails? a. the parental strand is methylated so the action of MutS/MutL/MutH proteins identifies, removes and replaces nucleotides on the unmethylated strand b. the newly synthesized DNA strand is temporarily methylated so the action of MutS/MutL/MutH proteins identifies, removes and replaces nucleotides on the methylated strand at the site of the mismatch c. Error correcting DNA polymerases IV and V are activated when LexI is cut and inactivated by autoproteolysis d. DNA glycolases remove damaged or unnatural basis
a
116. Investigators conducting a field study want to genotype the strains of Mycobacterium marinum that are responsible for a new outbreak in frogs that inhabit a distinct geographical region. They want to map the phylogenetic relationships between M. marinum isolates collected from fish in the same region and from past outbreaks in amphibian populations from other regions. What genotyping technology would be appropriate for this study? a. Analysis of SNPs from variable regions of several housekeeping genes b. Full genome sequencing of the frog and the infecting bacteria c. Sequencing of the V4 region of 16S rRNA genes d. DNA DNA hybridizations of the host frogs and fish
a
117. Protists contain all of the following forms of life EXCEPT a. fungi b. protozoa c. slime molds d. algae e. none of these options
a
120. What is the most compelling reason why DNA, rather than RNA, evolved to be the storage repository for genetic information in cellular life forms? a. DNA has a deoxyribose rather than ribose, so the DNA molecules are more chemically stable than RNA molecules. b. DNA is double stranded rather than single stranded. c. DNA has thymidine rather than uracil. d. DNA can adopt circular or linear configurations
a
136. The concept that human and animal diseases can be caused by microorganisms is called the a. germ theory b. cell theory c. causative agent hypothesis d. miasma theory
a
138. Rod shaped bacteria synthesize new cell walls over the entire surface of the cell . a. True b. False
a
145. What is the best form of microbial control you could use for purifying a protein from genetically modified E.coli? a. Filtration b. Hot air oven c. Autoclave d. Radiation
a
149. Foscarnet, a pyrophosphate analong, is used to treat ____ infections. a. Cytomegalovirus b. Human papillomavirus c. Influenza A d. HIV
a
153. The discovery of ribozymes was vital to our understanding of the origins of life since it provided an explanation for the evolution of coding and catalytic molecules. a. True b. False
a
157. Consider the biochemical pathway used to synthesize the amino acid proline. A high concentration of proline will most likely lead to a. A decrease in proline production b. A further increase in proline production c. No change in the rate of proline production d. Increased breakdown of proline e. Increased storage of proline
a
160. It is feasible that a regulatory enzyme can be both allosteric and covalently modified. Having both levels of regulation allows for the allosteric effectors to exert varying effects depending on the nature and number of the covalently bound chemical groups. a. True b. False
a
162. Plastoquinone is the primary electron acceptor for electrons leaving photosystem 2. a. True b. False
a
164. During glycolysis, a 6 carbon sugar diphosphate molecule is split into two 3 carbon sugar phosphate molecules a. True b. False
a
169. A single turn of the Krebs cycle (not including the prior formation of acetyl CoA from pyruvate) will yield a. 1 ATP, 3 NADH and 1 FADH2 b. 1 ATP, 2 NADH and 1 FADH2 c. 2 ATP, 2 NADH and 2 FADH2 d. 1 ATP, 2 NASH and 2 FADH2
a
172. Protons received from NADH a. Are pumped across the membrane b. Are the terminal electron acceptors c. Act as coenzymes d. Are passed along the electron transport chain along with the electrons
a
174. The energy captured in the phosphorylation of ADP to ATP comes from the PMF created when energy is released following the oxidation of electron carriers a. True b. False
a
176. Disaccharides can be directly ____ to their constituent sugars or may be split by a phosphate attack on the bond joining the two sugars, a process called ____. a. Hydrolyzed: phosphorolysis b. Hydrolyzed: anabolism c. Amalyzed: phosphorolysis d. Phosphorylzed: hydrolysis
a
180. Glyceraldehye 3 phosphate and 3phosphoglycerate are 3 carbon molecules produced during the calvin cycle a. True b. False
a
181. The calvin cycle functions to construct carbohydrates from carbon dioxide a. True b. False
a
187. Which part of the phage entered the bacterial cell following infection? a. DNA b. RNA c. Protein coat d. The entire phage e. No part
a
191. Which of the following was the major contribution made by Avery, MacLeod, and McCarthy that strengthened this argument that the transforming agent in Griffith's transformation experiment was DNA? a. Nonvirulent cells were not transformed only if purified, denatured DNA were added b. Nonvirulent cells were not transformed only if purified, denatured protein was added c. Nonvirulent cells were not transformed only if purified, denatured RNA was added d. Nonvirulent cells were not transformed when denatured DNA or RNA was added
a
199. Synthesis of the daughter DNA strand from the leading strand template occurs in a 5 to 3 direction a. True b. False
a
201. Following base removal, DNA polymerase can add nucleotides in the 5 to 3 direction a. True b. False
a
202. Improper base pairing during DNA replication causes a pause in chain elongation a. True b. False
a
203. DNA polymerase use their ____ activity to remove a mismatched base pair a. 3 to 5 exonuclease b. 5 to 3 exonuclease c. RNase d. Protease e. Mismatchase
a
208. The RNA transcript being produced by the RNA polymerase is complementary to the template strand of the DNA a. True b. False
a
216. An active repressor protein a. Binds to the DNA molecule ad prevent transcription b. Is a structural protein c. Binds to the RNA polymerase, preventing mRNA synthesis d. Binds to an inducer to activate it
a
217. When a microorganism such as E.coli is grown on glucose it is a. Capable of amino acid production b. Unable to synthesize a cell wall c. Incapable of amino acid production d. Unable to produce ATP e. Unable to produce its peptidoglycan layer
a
77. Which of the following components of PCR ensures amplification of the target DNA sequence only, despite the presence of many other DNA sequences? a. Primers b. Thermostable polymerase c. dNTPs d. High temperatures
a
11. In a landmark 1977 publication, Carl Woese and colleagues used ribosomal RNA sequence data to classify all life into the following domains (check all that apply): a. Eukarya b. Bacteria c. Archaea d. Fungi e. Prokarya
a,b,c
122. This question may have more than one correct answer. The SOS response in bacteria ______ (mark all that apply): a. can be induced in bacteria exposed to antibiotics b. can activate prophages integrated in the bacterial chromosome to convert to a lytic phase of the phage life cycle c. induces increased production of Shiga like toxin in EHEC d. is how gram positive bacteria initiate endospore formation
a,b,c
123. Which of the following is a characteristic of active transport? (Mark all that apply) a. Can be used to import nutrients that are extremely limited outside the cell b. Saturable uptake rate c. Use of ATP or a proton gradient is used as a source of metabolic energy d. Can move materials against a concentration gradient e. None of these options
a,b,c,d
124. The cytoplasmic membrane of bacteria ____ (Mark all that apply) a. is composed primarily of an ester linked phospholipids in a bilayer b. retains the cytoplasm and its contents c. acts as a selectively permeable barrier, allowing some molecules to pass while preventing the movement of others d. is the major site of ATP synthesis in aerobes. e. None of these options
a,b,c,d
125. Which of the following is/are true of capsules? (Mark all that apply) a. A polysaccharide layer that forms outside the cell envelope b. They help bacteria escape phagocytosis by host cells. c. They retain water and help prevent desiccation of the bacteria. d. They prevent entry of many bacterial viruses e. None of these options
a,b,c,d
128. Which are true about archaeal plasma membrane phospholipids? (It does not necessarily need to be true for all archaea members, but is true for some or most.) (Mark all that apply) a. Glycerol diether lipids form lipid bilayers b. Glycerol tetraether lipids that form monolayers are more rigid than the bilayers c. pentacyclic rings in the diester linked chains decrease rigidity d. the branched hydrocarbon chains are synthesized from isoprene units e. none of these options
a,b,d
147. Which of the following ways can heat be used to control microbes? a. Denature proteins b. Denature nucleic acids c. Cases thymine dimers in DNA d. Disrupts membranes e. Produces free radicals
a,b,d
129. What are correct about persistent viral infections? (Mark all that apply) a. Latent infections integrate into the host genome, but chronic infections do not b. Latent infections persistently shed low amounts of virions without killing the host cells c. Latent infections can activate into rapidly replicating, acute infections d. There are no effective treatments for long term persistent infections e. None of these options
a,c
154. Metabolic pathways can be regulated in three major pathways. Select the correct methods of metabolic pathway regulation from the choices below. a. Post translational regulation of enzyme activity b. Localization of all metabolic activity in the cytoplasm c. Regulation of protein expression d. DNA gene deletion before transcription e. Separate distribution of enzymes and metabolites in the cell
a,c,e
130. A virus that evolves to change its tropism is likely to have _______ (Mark all that apply) a. altered the proteins on its capsid or envelope so it can bind to a different type of host cell receptor b. mutated the polymerase gene c. gone into a latent state d. mutated so it infects a different type of host or a different tissue type e. None of these options
a,d
126. Which are true of the peptidoglycan strands: (Mark all that apply) a. the polysaccharide backbone of a strand forms a single stranded helix b. N acetylglucosamine (NAG) and N acetylmuramic acid (NAM) are present in the chain in a 2:1 ratio (NAG:NAM) c. the peptide side chains are covalently linked to Nacetyl glucosamine (NAG) d. the peptide side chains have D and L amino acids e. interstrand cross linking can happen via a direct bond between side chains of two adjacent strands
a,d,e
101. ATP has a phosphate transfer potential of 30.5, whereas glucose 6 phosphate has a phosphate transfer potential of 13.8. Based on these differences, which of the following will happen? a. ATP will transfer phosphate to glucose 6 phosphate. b. Glucose 6 phosphate will transfer phosphate to ADP forming ATP. c. Phosphates will not be transferred between these molecules. d. ATP will transfer phosphate to phosphoenolpyruvate
a.
109. Which is FALSE regarding the two component regulatory system in bacteria? a. The system involves a sensor kinase and a response regulator. b. The sensor kinase is phosphorylated by the response regulator when the extracellular environment changes. c. Regulation of OmpF and OmpC porin proteins in E. coli is modulated by this type of system. d. One part of the system is exposed to the external cellular environment while another part is exposed to the cytoplasm.
b
113. Transposable elements are important factors in the evolution of bacteria because they a. can enhance the spread of antibiotic resistance in humans. b. can transfer antibiotic resistance from one bacterial cell to another. c. cause lethal mutations in all cases. d. allow DNA to become resistant to treatment with UV light.
b
134. While each of these processes are believed to have evolved prior to aerobic respiration, which one is the most critical process, without which aerobic respiration could never have developed? a. anoxygenic photosynthesis b. Oxygenic photosynthesis c. alcohol fermentation d. lactic acid fermentation
b
142. Endocarditis occurs when bacteria infect the bloodstream and attach themselves to te inner lining of the hart r a defective heart valve. These bacteria are ____. a. Planktonic b. Sessile c. Budding d. Endospores
b
150. Most antiviral drugs target extracellular viruses. a. True b. False
b
152. During cellular respiration, cells obtain energy from foo molecules such as glucose by using which of the following reactions? a. Cells obtain energy from glucose by using phosphorylating reactions b. Cells obtain energy from glucose by using oxidation reduction reactions c. Cells obtain energy from glucose by using photosynthetic reactions d. Cells obtain energy from glucose b using anabolic reactions
b
156. During feedback inhibition the inhibitor binds to the a. Active site of the enzyme being inhibited b. Allosteric site of the enzyme being inhibited c. Both the active site and the allosteric site of the enzyme being inhibited d. Neither the active site nor the allosteric site of the enzyme being inhibited
b
159. Allosteric regulation involves the action of an effector molecule that binds the active site of an enzyme. By contrast, covalent modification involves the binding of a chemical group to the regulatory site of an enzyme which changes the conformation of the active site. a. True b. False
b
165. The net products from the oxidation of glucose to pyruvate in the Emden Meyerhof pathway are a. 4 NADH and 2 ATP b. 2 NADH and 2 ATP c. 4 NADH and 4 ATP d. 1 NADH and 1 ATP
b
170. Following the formation of acetyl CoA, the initial reaction of the Krebs cycle involves the addition of a a. 2 carbon molecule to a 5 carbon molecule b. 2 carbon molecule to a 4 carbon molecule c. 2 carbon molecule to a 5 carbon molecule d. 3 carbon molecule to a 4 carbon molecule e. 2 carbon molecule to a 6 carbon molecule
b
175. One example of the potential benefits of anaerobic respiration is a. Soil microbes using nitrate as an electron acceptor in anoxic soils b. Nitrate used by bacteria in a sewage treatment plant c. Depletion of oxygen by soil microbes in aerobic environments
b
182. Precursor metabolites in autotrophs are derived from the central metabolic pathway a. True b. False
b
183. The Lpt pathway for the synthesis of LPS exists because of which of the following? a. The carbohydrate portion of LPS is difficult to transport across the outer membrane b. The carbohydrate portion of LPS is difficult to transport across the periplasmic space c. The lipid A portion of LPS is difficult to transport across the outer membrane d. The lipid A portion of LPS is difficult to transport across the periplasmic space
b
189. In the Hershey an Chase experiment, radioactively labeled 32P a. Did not enter the cell b. Remained inside the cell after vigorous shaking c. Was removed from the cells by vigorous shaking d. And 35S remained inside the cells after vigorous shaking e. And 25S were removed from the cells after vigorous shaking
b
195. RNA primers are removed by the action of the enzyme a. DNA pol 3 b. DNA pol 1 c. Primase d. Helicase e. Phosphodiesterase
b
196. To allow simultaneous replication of the leading and lagging strands by dimeric DNA pol 3, the DNA of he leading strand has to be folded a. True b. False
b
197. What enzyme or protein prevents supercoiling of the DNA strands ahead of the replication bubble? a. Helicase b. Topoisomerase c. DNA binding proteins d. DNaA
b
200. Okazaki fragments are involved in the replication of the leading strand in a replication bubble a. True b. False
b
206. What statement is correct regarding sigma factor? a. It is involved in the termination of replication b. It recognizes the promoter region c. It forms an open complex d. It forms mRNA e. None of the above
b
207. Which of the following occurs first in transcription? a. Action of the Rho protein b. Formation of a holoenzyme c. Formation of an open complex d. Formation of a closed complex e. Elongation of the mRNA
b
209. Unwinding of the DNA during transcription is the result of the activity of a helicase enzyme downstream of the RNA polymerase a. True b. False
b
210. After the imitation step of protein synthesis, transfer of RNAs carrying amino acids bind to the ribosome at the _____ a. E site b. A site c. E, P, A site d. P and A site
b
211. The initiating transfer RNA, carrying formylmethionone, binds to which site? a. E site b. P site c. A site d. E, P, and A site e. P and A site
b
213. A stop codon codes for an amino acid as well as the signal to stop a. True b. False
b
177. For an organism to synthesize a protein, it must ____ a. Obtain energy to power protein synthesis b. Acquire amino acids from food or synthesize them from food c. Synthesize carbohydrates so the organism can generate energy d. Be at a temperature that isn't too hot or cold e. Be part of the entire enzymatic pathway of biosynthesis
b,c,e
186. Which nitrogenous bases are pyrimidines? a. Adenine b. Cytosine c. Guanine d. Thymine e. Uracil
b,d,e
167. Choose the answers that are end products of aerobic respiration a. NAD b. CO2 c. NASH d. Pyruvate e. GTP f. FADH g. ADP h. ATP i. FADH2
b,e,h
277. Why are pathogens that are transmitted person to person often less virulent than those transmitted by arthropod vectors? a. Vector borne transmission does not benefit the pathogen therefore it must maintain high virulence b. Person to person transmission requires the infected host to remain alive long enough to transmit the organism to another c. Vector borne pathogens harm both the host and the vector
b.
103. In order for a substance to transfer a phosphate to ADP in a substrate level phosphorylation reaction, which of the following must be true? a. The phosphate donor must have a lower phosphate transfer potential than ATP. b. The phosphate donor must have a higher oxidation reduction potential than ATP. c. The phosphate donor must have a higher phosphate transfer potential than ATP. d. The phosphate donor must have a lower oxidation reduction potential than ATP.
c
105. A facultative bacteria is grown in a media that provides peptides and amino acids as the sole carbon source. Over time, what molecule would be expected to be excreted into the media. a. Hydrogen gas b. Hydrogen sulfide c. Ammonium ions d. All of the choices are correct.
c
111. Which of the following is NOT a regulatory mechanism used to control the lactose operon in Escherichia coli? a. Induction b. Catabolite repression c. Attenuation d. The lac repressor (encoded by lacI) binds two operator sites to form a DNA loop that blocks RNA polymerase access to the 35 and 10 binding sites. e. All of the choices are correct.
c
114. Which of the following are true of specialized transduction? 1. It is carried out by temperate phage. 2. Specific portions of the bacterial genome are carried by the phage particle: these are limited to those genes on either side of an integrated prophage. 3. The phage genome retains the full complement of phage genes. 4. Errors in the excision process happen when the prophage genome is induced to leave the host chromosome 5. A headful of host chromosomal DNA is packaged in the phage capsid a. 1, 5 b. 2, 3, 4 c. 1,2,4 d. All are true
c
115. You isolate a bacteria from the Great Salt Lake in Utah. It is most likely a(n) a. Aerotolerant anaerobe b. Thermophile c. Halophile d. Acidophile
c
118. The studies that sequenced ribosomal RNA and led to the division of prokaryotic organisms into the Bacteria and the Archaea were begun by a. John Needham b. Louis Pasteur c. Carl Woese d. James Watson e. none of these options
c
137. The structure that divides the bacterial cell in two is termed the ____. a. Cell plate b. Cleavage furrow c. Cross septum d. Demarcation zone e. Fission line
c
141. When a broth culture of Bacillus begins to run out of nutrients, the cell ____. a. Form cysts b. Form persisters c. Form endospores d. Decrease their size
c
143. What are the mechanisms that halophiles typically employ to grow in habitats with high concentrations of salt? a. Production of a capsule to protect the cells from the hypersaline environments b. Increase the internal concentration of organic molecules such as choline c. Maintain high levels of potassium chloride and other inorganic solutes d. Utilize membrane proteins to pump water out of the cell and thereby dilute solutes
c
146. Using the D value method, how many organisms would be left after one decimal reduction if you started with 1000 bacteria? a. 900 b. 0 c. 100 d. 50
c
163. A microorganism that obtains its energy from the oxidation of chemical compounds (ether organic or inorganic) is referred to as ____. a. Phototroph b. Lithotroph c. Chemotroph d. Organotroph
c
168. Replenishing the supply of oxygen present in the Earth's atmosphere occurs through a. Anoxygenic phototroph b. Rhodopsin based phototroph c. Oxygenic photosynthesis d. All of the above
c
171. The movement of protons through ATP synthase in eukaryotes occurs from the a. Matric to the intermembrane space b. Matrix to the cytoplasm c. Intermembrane space to the matrix d. Intermembrane space to the cytoplasm e. Cytoplasm to the intermembrane space
c
173. When protons are pumped outside the cell membrane a. Water is made b. Electrons are lost c. A proton motive force is created d. NADH get reduced
c
179. The calvin cycle begins by the attachment of CO2 to which of the following? a. Glucose b. 3 phosphoglycerate c. RuBP d. Glyceraldehyde 3 phosphate e. None of the above
c
184. What type of compound are the substrates for transaminases? a. Sugars b. Nucleotides c. Amino acids d. Lipids
c
192. Arrange these replication proteins in proper order in which thy participate in DNA replication. 1) primase, 2) helicase, 3) single stranded binding proteins, 4) DNA polymerase 1 a. 1,2,3,4 b. 1,3,2,4 c. 2,3,1,4 d. 2,3,4,1 e. 2,4,3,1
c
198. What molecule initiates the formation of the replication bubble? a. Helicase b. DNA polymerase c. DnaA d. Topoisomerase e. DNA primase
c
205. The Rho protein is involved in the ____ stage of transcription a. Initiation b. Elongation c. Termination d. None of the above
c
215. DNA in cells can encode thousands of different proteins. Why do cells require mechanisms to regulate expression of the genes that code for these proteins? a. There are a limited number of genes available for making proteins, proteins derived rom all genes cannot all be made simultaneously b. In order to develop, a cell must be able to make every protein that is possesses a gene for it must have the ability to turn off the genes that aren't needed as it develops into each different cell type c. Not all proteins are needed at all times, or in equal amounts. Regulating their expression saves energy and times d. There are unlimited genes available for making proteins, but limited amounts of energy to do so
c
41. Chemolithotrophs generally derive ________ ATP from oxidation of inorganic substrates because the reduction potentials of those substrates are much more ________ than the reduction potential of organic substrates. a. more,positive b. more, negative c. less, positive d. less, negative
c
185. Which nitrogenous bases are purines? a. Adenine b. Cytosine c. Guanine d. Thymine e. Uracil
c,a
140. Select all that apply to the structure and function of the FtsZ protein in relationship to bacterial cytokinesis a. It is similar to the structure and function of eukaryotic tubulin b. It is found in some bacteria and archaea c. It is the major component of the Z ring in bacteria d. It plays a role in the invagination of te bacterial plasma membrane to split a dividing cell e. It is similar in structure and function to eukaryotic actin
c,d,e
102. When nitrate is used as a final electron acceptor by bacteria growing in anoxic soils, the nitrogen is no longer available for the construction of precursor metabolites. This is referred to as a. nitrifying. b. nitrogen fixation. c. nitrogenous respiration. d. dissimilatory nitrate reduction.
d
104. Nitrogen fixation depends on the enzyme nitrogenase, which is produced by some ______. a. Archaea b. bacteria c. eukaryotes d. bacteria and Archaea but no eukaryotes e. fungi and bacteria
d
106. For bacterial fermentation, which of the following are true: 1. Oxygen is consumed 2. Electron transport is not used to reoxidize NADH 3. In general, the ATP yield per glucose is about the same as for respiration 4. ATP is formed exclusively by substrate level phosphorylation 5. bacteria capable of anaerobic respiration suppress synthesis of ETC components during aerobic conditions and rely on fermentation for energy production 6. If NAD+ is not regenerated, glycolysis would stop, so cells use pyruvate as the electron acceptor 7. Different fermenting bacteria can convert pyruvate into a variety of organic acid or alcohol products that are secreted into the extracellular environment a. 1, 2, 3 b. 1, 3, 5 c. 2, 4, 5 d. 2, 4, 6, 7
d
110. Acylhomoserine lactones used in quorum sensing regulate their own synthesis by a(n) ____________ system. a. riboswitch b. antisense c. catabolite repression d. autoinduction
d
212. What type of bond is found connecting amino acids together during protein synthesis? a. Ionic bonds b. Phosphodiester bonds c. Hydrogen bonds d. Peptide bonds e. Ester bonds
d
148. The drug azidothymidine (AZT) ______. a. Inhibits uncoating of the viral nucleic acid b. Prevents the release of viruses from infected human cells c. Prevents the binding of the virus to human cells d. Blocks the production of capsid proteins e. Inhibits replication of the viral nucleic acid
e
151. In living organisms, ATP is most commonly used practical form of energy. Review your knowledge of ATP by analyzing its components. a. ATP is composed of adenine only b. ATP is composed of adenine and the pentose sugar ribose c. ATP is composed of adenine and the pentose sugar ribose and one phosphate d. ATP is composed of adenine and the pentose sugar ribose and two phosphates e. ATP is composed of adenine and the pentose sugar ribose and three phosphates
e
158. Pick the most complete answer below for regulation of a multibranched pathway. Regulation of multibranched pathways can be due to feedback inhibition ____. a. Of the initial pacemaker enzyme b. Of the branchpoint enzyme c. By the presence of isoenzymes d. Of the initial enzyme and the branchpoint enzyme e. Of the initial enzyme, the branchpoint enzyme and by the presence of isoenzyme
e
161. The hgh energy electrons of photosystem 1 are directly passed on to ____. a. Plastocyanin b. ATP synthase c. NADP reductase d. Plastoquinone e. Ferrodoxin
e
178. The calvin cycle uses ____, which are products of the light reactions of photosynthesis a. ADP and NADH b. 3 phosphoglycerate and glucose c. CO2 and H20 d. RuBP and O2 e. ATP and NADPH
e
204. The proofreading function of DNA polymerase reduces the error rate from about one/million base pairs to about one/_____base pairs a. Hundred thousand b. Ten thousand c. Thousand d. Ten million e. Hundred million
e
15. What microscope would be the best to use to view cell surface features of a specimen? a. Scanning electron b. Fluorescence c. Phase contrast d. Transmission electron
a
62. Methyl accepting chemotaxis proteins (MCP's) of E. coli are involved with a. sensing a chemical gradient of attractants and initiating the signal transduction that leads to rotation of the flagellar motor b. producing the second messenger molecules c di UMP c. regulation of the lac operon in the presence of lactose d. regulation of flagellum assembly
a
93. Choose the correct statement about T cells and their cluster of differentiation receptors. a. CD3 is a heterodimeric receptor found on all T cells: it can be one of two possible TCR dimers, either alpha/beta or gamma/delta. b. T cytotoxic cells carry the cluster of determination receptor CD4, which allows them to receive signals for the coordination of the immune response and the activation of B cells. c. CD8 T cells do not directly kill target cells: instead, they proliferate, thereby increasing the number of CD8 cells that can react to the antigen. d. T helper cells carry the cluster of determination receptor CD8, which allows them to receive signals for the destruction of targeted cells.
a
43. Beta oxidation is the process of sequentially digesting fatty acids, which are a rich source of energy in the cell. What is directly produced by one cycle of the beta oxidation pathway? a. 5 ATP, 2 NADH+H+ b. 1 acetyl CoA, 1 NADH+H+ , 1 FADH2 c. 2 ATP, 1 pyruvate d. 1 beta carotene, 4 ATP
b
45. Under anaerobic conditions, the end product of glycolysis may be converted to _________ by fermentation. a. hydrochloric acid b. lactic acid c. CO2 and H2O d. amino acids
b
55. What statement is correct regarding sigma factor? a. It is involved in the termination of replication. b. It recognizes the promoter region. c. It forms an open complex. d. It forms mRNA. E. None of the choices are correct.
b
61. Temperate phages establish lysogeny by a. hydrolyzing host cell DNA b. inserting their genome into the bacterial chromosome to become a prophage c. packaging a headful of bacterial chromosome into the capsid d. inducing the regulon that is involved in the biosynthesis of the sex pilus.
b
54. A bacterial __________ is the nontranscribed region of the DNA to which RNA polymerase binds in order to initiate transcription. a. operon b. operator c. promoter d. initiator
c
59. Generalized transduction occurs during a. the lysogenic cycle of all temperate phages. b. the lytic cycle of all phages. c. the lytic cycle of virulent and some temperate phages. d. the lysogenic cycle of virulent phages.
c
74. What is the best form of microbial control you could use for a soft, plastic, surgical device that will melt at high temperatures? a. Filtration b. Hot air oven c. Radiation d. Autoclave
c
71. Antifungals have a selective toxicity that targets which aspect of fungal cell biology? a. Cell wall synthesis b. Intron removal and exon splicing c. Protein secretion d. Cell membrane synthesis
d
83. When members of the normal microbiota of the human body become pathogenic and produce disease under certain circumstances, they are referred to as ______________ pathogens. a. partial b. conditional c. occasional d. opportunistic
d
85. Dinoflagellates that exist endosymbiotically within a variety of marine invertebrates, including coral, are called a. endoflagellates. b. parasites. c. endotrophic. d. zooxanthellae.
d
24. Archaea with a plasma membrane composed of a tetraether monolayer would most likely be found ______. a. at a temperature of 90C b. in an anaerobic environment c. in the mammalian gut d. in the soil e. at a pH of 2 or lower
a
29. In a chemostat, the addition of nutrients provides energy for the microbes in culture. When nutrients are limiting, microbes first use the available energy for _____, then as nutrients increase they use the additional available energy for _____. a. maintenance: reproduction B.reproduction: maintenance c. fermentation: reproduction d. growth: maintenance
a
31. Obligate anaerobes are usually poisoned by molecular oxygen but may grow in aerobic habitats if associated with facultative anaerobes that use up all available oxygen. a. True b. False
a
32. The site of septum formation in E. coli is dtermined by the cooperation of MinCDE proteins. Which of the following statements regarding the positioning of the septum are correct? a. The concentration of MinC proteins is lowest in the midpoint of the cell. b. The concentration of MinC proteins is highest in the midpoint of the cell. c. MinC proteins are fixed at the site of septum formation. d. MinC proteins form the scaffold for septum construction.
a
33. The textbook gives the example of the archaeon Sulfolobus to illustrate how the archaeal cell cycle system resembles the eukaryotic cell cycle in some ways and the bacterial cell cycle in others. In which way is the cell cycle of the archaeon Sulfolobus similar to the bacterial cell cycle? a. Homologous proteins for DNA segregation b. Homologous proteins for cytokinesis c. Presence of MinD homologues d. Presence of FtsZ homologues
a
48. During ____________ proteins are moved from the cytoplasm to the membrane or periplasmic space, while during ____________ proteins are moved from the cytoplasm to the external environment. a. translocation: secretion b. secretion: translocation c. transcription: translation d. translocation: translation e. secretion: translation
a
52. The βjelly roll of the Lpt system functions to a. help transport lipid A portion of LPS across the hydrophilic periplasm and to the outer membrane. b. anchor the newly positioned LPS on the bacterial cell surface. c. help attach the fatty acids of the lipid A to the core oligosaccaride. d. help attach the O antigen to core oligosaccharide moieties during synthesis of LPS.
a
58. Transposons can cause mutations by a. "jumping" into a gene and disrupting its function. b. inducing uncontrolled binary fission. c. replacing specific nucleotides in the original DNA. d. intercalating into the helix of double stranded DNA
a
73. Using the decimal reduction time (Dvalue) method, how many organisms would be left after one decimal reduction if you started with 1,000 bacteria? a. 100 b. 10 c. 0 d. 900
a
9. The concept of the pan genome helps explain the variety of different genes that can be found between members of the same taxa, but some genes are not necessarily shared by all the members. Horizontal (lateral) gene transfer is the mechanism that primarily drives this variability in gene content within the taxa. a. True b. False
a
98. Many gram negative bacteria within a biofilm communicate information in a cell densitydependent manner using a. Acylhomoserine lactones as autoinducers b. Autoinducer peptides c. The ppGpp second messenger d. Cell to cell contact inhibition
a
7. Many clinical microbiology laboratories and public health laboratories use techniques such as microbial staining, microbial growth, enzymatic testing, fermentation testing, and microscopic analysis to identify pathogens in samples. Which categories of classical characteristics for taxonomy are represented here? (Check all that apply.) a. Morphological characteristics b. Physiological and metabolic characteristics c. Biochemical characteristics d. Molecular/genetic characteristics
a,b,c
1. What important lesson(s) can be drawn from the case study on the Ebola virus outbreak? (Mark all that apply) a. Outbreaks in a new geographic area that arise (from patient travel, for example) can catch the health care system unprepared to adequately treat the patient and prevent further infections. b. Health care workers can be particularly vulnerable to infection, especially during the initial stages of an outbreak. c. Some Ebola outbreaks can be highly lethal, killing 57% of health care workers who get infected. d. Laboratory workers can contract the ebola virus by direct contact with a infected blood or body fluids
a,b,c,d.
14. The spore layer containing peptidoglycan is the ______. a. inner membrane b. cortex c. germ cell wall d. sporangium e. protein coat
b
40. Following the formation of acetyl CoA, the initial reaction of the Krebs cycle involves the addition of a a. 2 carbon molecule to a 5carbon molecule. b. 2 carbon molecule to a 4 carbon molecule. c. 3 carbon molecule to a 4 carbon molecule. d. 2 carbon molecule to a 6 carbon molecule. e. 3 carbon molecule to a 5 carbon molecule.
b
72. Each of the following possible adverse effects could happen under circumstances when an antibiotic is used incorrectly. Which one is most directly a result of incorrect antibiotic use? a. Allergic reaction b. Toxic effects at high concentrations c. Suppression of the normal flora d. Resistance to an antibiotic
b
37. Molecules such as ammonia, nitrite, and H2S have more positive reduction potentials than the NAD(P)+/NAD(P)H conjugate redox pair. How do chemolithotrophs transfer electrons to the less positive NAD+ from the more positive inorganic energy sources they utilize as fuels in order to gain reducing power? a. They do not produce NADH, eventually the pathway halts when the NAD+ can no longer be reduced. b. Electrons are pushed against their gradient by hydrolysis of ATP hence the low yield. c. They use reverse electron flow, whereby electrons are pushed against their gradient by diverting energy from the proton motive force. d. Transferring electrons from ammonia, nitrite and H2S to NAD+ is thermodynamically favorable, the reaction occurs spontaneously.
c
16. Sterol like molecules called hopanoids are thought to be important for the structural integrity of many bacteria because of their suspected function in membrane stabilization. a. True b. False
a
36. Pathways with enzymes that function both catabolically and anabolically are called amphibolic pathways. These pathways have an advantage in that they a. save energy and materials by using many of the same enzymes for both types of reactions. b. save energy by employing electron transport chains to enhance their effectiveness. c. import enzymes from outside the cell to enhance their productivity and effectiveness.
a
38. Choose the answer below that represents the correct sequence of events during photosynthesis. a. Photosystem II (ATP production) > Photosystem I (NADPH production) b. Photosystem I , ATP production , Photosystem II , NADPH production c. Photosystem II (NADPH production) > Photosystem I (ATP production) d. Photosystem I (NADPH production) > Photosystem II (ATP production)
a
42. Aerobic respiration, anaerobic respiration, and fermentation are the three basic types of a. chemoorganoheterotrophic metabolism. b. photolithoautotrophic metabolism. c. chemolithoautotrophic metabolism. d. chemoorganoautotrophic metabolism.
a
60. It is easier to transform bacteria with plasmid DNA than linear DNA since plasmids a. can independently replicate within the host and are not as easily degraded as are linear fragments. b. are readily degraded by cellular nucleases but can independently replicate within the cell. c. cannot replicate within the host without induction by outside signals. d. are packaged within a transducing phage
a
63. An example of the diauxic shift in the growth of E.coli in a closed system happens when a. the cell uses glucose first followed by a short lag as the cell synthesizes enzymes for lactose catabolism before reentering exponential growth. b. cyclic AMP (cAMP) is sequestered into a branched polymer c. the stress response sigma factor becomes dominant in global gene expression d. translation of target genes for the transition to facultative growth are blocked.
a
69. Why does treatment to combat HIV/AIDS typically involve drug combinations? a. HIV frequently develops drug resistance. b. Multiple drugs are needed to eliminate the proviral HIV DNA in the host cells. c. It lowers the overall cost of treatment. d. Different drugs are needed by men and women.
a
79. When performing a transformation experiment, antibiotics included in the culture medium can a. select against organisms that have not incorporated the plasmid with the resistance gene. b. select against organisms that have incorporated a plasmid with the resistance gene but do not contain the desired gene fragment insert. c. enhance production of recombinant proteins. d. select against organisms that have not incorporated the plasmid and select against organisms that have incorporated a plasmid not containing the desired gene
a
81. A molecular biologist treats a 600 bp length of linear DNA with a HindIII restriction endonuclease. Following gel electrophoresis, the biologist observes that there is only one band on the gel corresponding with the migration distance of the 200 bp molecular weight marker. Assuming that no procedural errors were made, what can be concluded from these results? a. Two HindIII recognition sequences were present in the original DNA. b. Three HindIII recognition sequences were present in the original DNA. c. There were no HindIII recognition sequences present in the original DNA. d. One HindIII recognition sequence was present in the original DNA.
a
99. Lactate dehydrogenase catalyzes the interconversion of pyruvate and lactate using NADH and NAD+ as follows: Pyruvate +NADH « lactate + NAD+ This is an example of what classification of enzyme reaction: a. Oxidoreductase b. Transferase c. Isomerase d. Ligase
a
*2. The toxin produced by the Enterohemorrhagic Escherichia coli (EHEC) __________? (complete the sentence with an accurate statement.) a. remains active even after it is cooked at high temperature. b. is encoded by an bacteriophage integrated into the E.Coli genome. c. enables the bacterial cell to attach to the human intestine. d. highly related to the toxin that causes Cholerae.
b
21. Organisms usually have only a single transport system for any specific nutrient. a. True b. False
b
23. If you found a microbe with an S layer as the major component of its cell wall, what is the most likely classification of this microbe? a. a gram negative bacterium b. an archaeon c. a eukaryote d. a gram positive bacterium
b
28. If a scientist is trying to grow an organism that the exact nutritional requirements are not known, it would be best to use this type of medium to grow it. a. Defined b. Complex c. Selective
b
30. Organisms that grow well at 0°C and have optimum growth temperatures of 15°C or lower are called______ a. psychrotrophs. b. psychrophiles. c. frigiphiles. d. mesophiles.
b
87. Superantigens ________. a. do not stimulate as many T helper cells as do antigens that bind with greater specificity b. bind without antigen specificity to the outer portion of the T cell receptor on T helper cells and the outer surface of the MHC II complex on antigen presenting cells (APCs) c. bind with antigen specifically to T helper cell receptors d. bind to about 1 in 10,000 T cells E. are bound inside specific MHC II antigens on APCs
b
91. Which of the following statements about antigen presenting cells is correct? a. Macrophages present foreign peptides to B cells and stimulate them to become activated B cells. b. Dendritic cells are particularly adept at presenting foreign peptides to T cells and stimulating them to become activated T cells. c. Antigen fragments are combined by the APC with preformed class I MHC molecules and are delivered to the cell surface. d. Macrophages, dendritic cells, or T cells take in the antibody by receptor mediated endocytosis or phagocytosis and produce peptide fragments by digestion in the phagolysosome.
b
22. The term for membranes that allow some molecules to pass but not others. a. Permeable b. Inverted monolayer c. Selectively permeable d. Impermeable
c
25. An archaeon in a nutrient poor environment is most likely to use __________________ for nutrient uptake. a. group translocation b. facilitated diffusion c. ABC transport d. passive diffusion
c
34. Think about the properties of microbes growing in an oligotrophic environment. Cells in which of the stages of the typical bacterial growth curve most resemble cells growing in an oligotrophic environment? a. Exponential phase b. Lag phase c. Stationary phase d. Death phase
c
39. During electron transport, protons received from NADH a. are the terminal electron acceptors. b. act as coenzymes. c. are pumped across the membrane. d. are passed along the electron transport chain along with the electrons.
c
49. Fatty acids are called saturated when their _______. a. Fatty acid tails bend (i.e., they are not straight) b. Glycerol contains a phosphate group c. Carbon atoms are maximally bound to hydrogen atoms d. Carbon atoms have double bonds with other carbon atoms
c
17. Bacterial flagella are composed of three major structural parts: the part embedded in the cell membranes and periplasmic space is called the _________. a. anchor b. hook c. flagellum d. basal body
d
18. The lipopolysaccharide (LPS) that is found in the outer membrane of gramnegative bacteria is also known as a. exotoxin. b. teichoic acid. c. murein. d. endotoxin.
d
27. What percentage of microorganisms can be cultured in the laboratory? a. 100% b. 50% c. 25% d. 1%
d
35. How many generations does it take for a single bacterial cell to become 256? a. 5 b. 6 c. 7 d. 8 e. 9
d
44. A facultative bacteria is grown in a media that provides peptides and amino acids as the sole carbon source. Over time, what molecule would be expected to be excreted into the media. a. Hydrogen sulfide b. Hydrogen gas c. Sulfate ions d. Ammonium ions
d
47. The construction of many very different amino acids from a single precursor typically uses which of the following "types" of biochemical pathways? a. Cyclic pathways b. Negative feedback pathways c. Direct pathways d. Branched pathways
d
51. Nitrogen fixation depends on the enzyme nitrogenase, which is responsible for the reduction of nitrogen (N2) to ammonia NH3). Nitrogenase is produced by some ______. a. Archaea and plants b. Bacteria and algae c. Eukaryotes d. bacteria and Archaea but no eukaryotes e. fungi and bacteria
d
56. Transformation with a linear DNA fragment may result in a. homologous recombination. b. unsuccessful transformation. c. formation of an episome. d. either homologous recombination or unsuccessful transformation.
d
57. Hfr strains contain the F factor integrated into their ________, rather than in the __________. a. chromosome: mitochondrial DNA b. chromosome: chloroplast c. cytoplasm: chromosome d. chromosome: cytoplasm
d
65. Proofreading DNA polymerases use their ________ activity to remove a, mismatched basepair or basepairs. a. protease b. 5' → 3' exonuclease c. mismatchase d. 3' → 5' exonuclease e. RNase
d
68. Why are there far fewer antiviral agents than there are antibacterial agents? a. Viruses always incorporate part of their nucleic acid into their host. b. Viruses are much more similar to human cells than are bacteria. c. Viruses become drug resistant much faster than bacteria. d. Viruses enter host cells and make use of host components.
d
70. A young man arrives at the hospital with a Staphylococcus infection. A microbiologist at the hospital runs a disk diffusion test and obtains a zone diameter of 17 mm for clindamycin. The zone diameter interpretive standards for this drug microbe combination are listed as: Resistant = <15, Intermediate = 1520, Susceptible = >20. How should the results of this disk diffusion test be interpreted? a. he Staphylococcus can not be killed by the use of the antibiotic clindamycin. It would not be recommended to use this antibiotic for this infection. b. The Staphylococcus shows some susceptibility to the antibiotic clindamycin. It would be recommended to use this antibiotic for this infection. c. The Staphylococcus can be killed by the use of the antibiotic clindamycin. It would be recommended to use this antibiotic for this infection. d. The Staphylococcus shows some susceptibility to the antibiotic clindamycin. It would not be recommended to use this antibiotic for this infection.
d
86. Which of the following statements is correct about innate and adaptive immunity? a. The innate immune system is able to generate an enormous diversity of molecules such as cellular receptors and soluble proteins, including antibodies, that recognize trillions of different foreign substances. b. The innate immune system almost always responds selectively to nonself and produces responses tailored to protecting against that type of stimulus. c. Innate immunity is highly selective in that it can be directed against one particular pathogen or foreign substance. d. When reexposed to the same pathogen or substance, the adaptive response of the host reacts so quickly that there is usually no noticeable illness.
d
89. Which of the following statements about activation of B cells is correct? a. T dependent antigen triggering of a B cell occurs when an activated, antigen presenting dendritic cell directly associates with the B cell displaying the same antigen MHC complex. b. Antigens that elicit a response with the aid of T helper cells are called T independent antigens. c. B cells that are specific for a given epitope on an antigen cannot develop into plasma cells that secrete antibody without the collaboration of T helper cells. d. B cells can be activated to produce antibody without stimulus from T cell, but he T independent antigens tend to be polymeric: that is, they are composed of repeating sugars or amino acids, and the resulting antibody generally has a relatively low affinity for antigen.
d
95. What is NOT true of immunoglobulin classes? a. IgG and IgM are most effective at activating the classical complement pathway b. IgG has a much longer half life in serum than all the other classes. c. IgE is primarily effective for immunity to parasites and helminths d. The serum concentration of IgA is the earliest to increase in response to an antigen
d
97. The order of the phases of the growth curve of a bacterial culture in a closed system are: a. Long term stationary, Exponential, Lag, Stationary, Death b. Exponential, Lag, Stationary, Long term stationary, Death c. Stationary, Lag, Exponential, Long term stationary, Death d. Lag, Exponential, Stationary, Death, Long term stationary
d
*5. The 2014 Nobel Prize for Chemistry was awarded to three scientists who made important contributions toward _____ (complete the sentence to make it an accurate statement). a. technologies that led to super resolution fluorescence microscopy and effectively overcame "Abbe's limit." b. defining a three domain system of life on earth. c. discovering the postulates for identifying the microbe that causes an infectious disease. d. discovering that genes encoded by prophages can be activated by the presence of antibiotics.
a
100. Arrange the following electron carriers in the electron transport chain, based on their standard reduction potentials. (Ubiquinone is also called Coenzyme Q: this Q needs to specify the direction.) Cytochrome a3(Fe3+) + e → Cytochrome a3 (Fe2+) Eo (volts) = 0.35 Ubiquinone + 2H+ + 2e → Ubiquinone + H2 Eo (volts) = 0.10 Cytochrome a (Fe3+) + e → Cytochrome a (Fe2+) Eo (volts) = 0.29 Cytochrome c (Fe3+) + e → Cytochrome c (Fe2+) Eo (volts) = 0.25 a. ubiquinone ,cytochrome c, cytochrome a, cytochrome a3 b. cytochrome a3 , cytochrome a ,cytochrome c , ubiquinone c. ubiquinone, cytochrome a, cytochrome a3, cytochrome c d. cytochrome c, ubiquinone, cytochrome a, cytochrome a3
a
19. Lipids with polar and nonpolar ends are labeled: a. amphipathic. b. amphibolic. c. bilateral d. dihydrophobic
a
75. Which antimicrobial control method is best suited as an antiseptic and noncorrosive for surgical plastics? a. Iodophors b. Quaternary ammonium compounds c. Phenols d. Formaldehyde
a
76. A (n) __________ vector contains sequence features that enable the plasmid to replicate in host cells of different species. a. shuttle b. chimeric c. expression d. phage
a
78. When Nitrobacter utilizes nitrite produced from ammonia by Nitrosomonas to obtain energy by converting the nitrite to nitrate, the relationship between the two organisms is a. commensal. b. amensal. c. mutual. d. parasitic.
a
84. A researcher proposes that the relationship between a particular bacterial species that produces a fat soluble vitamin is mutualistic with its insect host. Which of the following procedures would best test the researcher's hypothesis? a. Determine which antibiotic kills the bacteria without harming the host, then administer this antibiotic to the insect and compare its growth with and without the vitamin b. Determine which insecticide kills the insect without harming the bacterial host, then compare vitamin production by the bacteria from insects treated with the insecticide to those from untreated insects c. Design a method to isolate the bacteria from the insect, then mutate the bacteria in the region of DNA that controls vitamin production and compare growth of the mutant and wild type bacteria on minimal media d. Extract the DNA from the bacteria and from the insect, then use reversetranscriptase PCR and primers specific to the gene that controls vitamin synthesis to compare transcription of RNA in both organisms
a
90. Which of the following statements is correct about antigen presentation by class I and class II MHC molecules? a. The class I MHC molecule is presented on the surface together with its endogenous antigen, enabling the host cell to present the antigen to a subset of T cells known as cytotoxic T lymphocytes. b. An antigen presenting cell (APC), such as a macrophage, dendritic cell, or B cell, takes in the MHC molecule by receptor mediated endocytosis or phagocytosis and produces MHC fragments by digestion in the phagolysosome. c. Class I MHC molecules bind to fragments that initially come from antigens outside the cell, thus they undergo exogenous antigen processing. d. Class II MHC molecules bind to fragments that initially come from antigens outside the cell, thus they undergo endogenous antigen processing.
a
94. Which of the following statements is correct about the development of T cells? a. T cells differentiate from progenitor cells destined to become (1) natural T regulatory (Treg) cells, (2) natural killer T (NKT) cells, (3) gamma/delta T cells, and (4) alpha/beta T cells. b. After many cell generations, some of the CD8+ TH cells differentiate into at least six functional phenotypes. c. Activation by its specific antigen causes a TH cell to mature into a cytotoxic T lymphocyte (CTL) that functions to destroy host cells that have been infected by intracellular pathogens, such as a virus, or have altered MHC surface proteins. d. T cells originate from CD34 positive stem cells in the bone marrow, where they also complete their maturation process before circulating in the peripheral blood.
a
66. Some drug resistant organisms produce β lactamases, enzymes that hydrolyze the β lactam ring. Clavulanate is a chemical compound that works to inactivate βlactamase enzymes. Which antibiotic would you find coprescribed with clavulanate as a means of combating drug resistant infections? a. Erythromycin b. Amoxicillin c. Ciprofloxacin d. Tetracycline
b
67. Staphylococcus aureus treated with chloramphenicol has the following values: minimum inhibitory concentration = 3 μg/ml minimum lethal concentration = 50 μg/ml Chloramphenicol is acting in a ______ manner against Staphylococcus aureus. a. Bacteriocidal b. bacteriostatic c. broad spectrum d. resistant
b
20. Which of the following statements about the periplasmic space are true (check all that are correct): a. It is found only in gram positive bacteria. b. It is located between the plasma membrane and outer membrane of gram negative bacteria. c. It contains hydrolytic enzymes and binding proteins involved in nutrient acquisition. d. Gram negative bacteria tend to have a larger periplasmic space with a greater diversity of proteins than Gram positive bacterial.
b,c,d
10. What molecular entity of the polar end of the phospholipid that composes the lipid bilayer of the plasma membrane? a. long chain fatty acid b. glycerol c. ethanolamine d. hopanoid
c
12. Which of the following bacterial genera is/are described CORRECTLY? a. Clostridium: club shaped rod b. Corynebacterium: spore forming rod c. Vibrio: curved rod d. Corynebacterium: spore forming rod and Vibrio curved rod
c
50. The Calvin Benson Cycle incorporates CO2 into organic material, this is a(n) ________ process. a. exergonic b. spontaneous c. endergonic d. catabolic
c
53. In order to form a single molecule of glucose, it takes ______ turns through the reactions of the Calvin Benson cycle. a. 3 b. 4 c. 6 d. 12
c
8. An unrooted tree containing four unrelated species can become rooted by adding: a. a descendant group related to two of the species. b. an unrelated outgroup. c. a distantly related outgroup. d. a descendant related to only one of the species
c
80. A PCR procedure that allows a determination of the relative amount of a particular DNA fragment that is present in a sample is called a. inversion PCR. b. analytical PCR. c. real time PCR. d. reverse PCR.
c
82. Movement of charged molecules in an electrical field, which is used to separate nucleic acid fragments for recombinant DNA work, is called a. iontophoresis. b. nucleophoresis. c. electrophoresis. d. plasmaphoresis.
c
88. Antibodies are produced by _________. a. helper T cells b. macrophages c. plasma B cells d. memory B cells e. cytotoxic T cells
c
92. Which of the following statements about cluster of differentiation (CDs) molecules is correct? a. Unfortunately, the presence of various CDs on the cell's surface cannot be used to determine the cell's identity. b. CDs often are used in a classification system to differentiate between epithelial cell subpopulations. c. CDs have both biological and diagnostic significance. Because they are anchored in the membrane and externally exposed on the cell surface, they make excellent markers for immune cells circulating in peripheral blood or extracted from tissue sites such as the bone marrow. d. Erythrocytes bear cell surface proteins that have specific roles in intercellular communication and are called cluster of differentiation (CDs) molecules.
c
96. Of the five functions listed below, select all that apply to the structure and function of the FtsZ protein in bacterial cytokinesis. 1) It is similar in structure and function to tubulin, the building block of the microtubule cytoskeleton in eukaryotes. 2) it builds filaments that form a ring around the longitudinal midpoint, or septum, of the bacterial cell 3) It acts in chromosome partitioning by depolymerizing to pull one copy of the replicated DNA chromosome to the opposite pole in the bacterial cell. 4) It plays a role in the invagination of the bacterial plasma membrane to split a dividing cell. 5) It is similar in structure and function to eukaryotic actin, the multifunctional protein that forms microfilaments. a. 1, 2, 3 b b. 3, 5 c. 1, 2, 4 d. 2, 4, 5
c
*3. How many bacteria are estimate to be associated with an adult human body? a. 300,000 b. 39 million c. 39 billion d. 39 trillion
d
*4. Hays County Health Department recently reported that Influenza cases this season are different from last season by how much? a. down 50% b. increased 50% c. increased 200% d. increased 2000% (20 fold higher)
d
*6. A population descending from a single organism or pure culture isolate is called a ______. a. genus b. species c. subspecies d. strain
d
13. The movement of dissolved solutes from a region of higher concentration to a region of lower concentration is called _______. a. isotonic b. osmosis c. hypotonic d. diffusion
d
64. Effective translation of mRNA transcripts in bacteria can be prevented by a. trans encoded, small, noncoding RNAs (designated sRNAs or ncRNAs) b. cis encoded antisense RNAs that form a duplex with the mRNA transcript c. the 5' untranslated region of an mRNA that contains an effector binding element and can obstruct access of the ribosome to the Shine Delgarno sequence. d. all of the above
d