MULTIPLE CHOICE.  Choose the one alternative that best completes the statement or answers the question.


1)  Which of the following pairs is mismatched?


A) Spliceosome - removal of introns


B) Transposase - insertion of DNA segments into DNA


C) DNA polymerase - makes a molecule of DNA from a DNA template


D) RNA polymerase - makes a molecule of RNA from an RNA template


E) DNA ligase - joins segments of DNA


2)  Which of the following statements is false?


A) The leading strand of DNA is made continuously.


B) Multiple replication forks are possible on a bacterial chromosome.


C) DNA replication proceeds in one direction around the bacterial chromosome.


D) The lagging strand of DNA is started by an RNA primer.


E) DNA polymerase joins nucleotides in one direction only.


3)  Which of the following is not a product of transcription?






C) A new strand of DNA




E) None of the above


Table 8.1

                  Culture 1:  F+, leucine+, histidine+

                  Culture 2:  F-, leucine-, histidine-



4)  In Table 8.1, what will be the result of conjugation between cultures 1 and 2?


A) 1 will remain the same;

2 will become F+, leucine-, histidine-


B) 1 will remain the same;

2 will become F+ and recombination may occur


C) 1 will become F-, leu-, his-;

2 will remain the same


D) 1 will remain the same;

2 will become F+, leu+, his+


E) 1 will become F-, leu+, his+;

2 will become F+, leu-, his-






5)  An enzyme produced in response to the presence of a substrate is called


A) A repressible enzyme.


B) A restriction enzyme.


C) An operator.


D) An inducible enzyme.


E) A promoter.






6)  Transformation is the transfer of DNA from a donor to a recipient cell


A) By sexual reproduction.


B) By cell-to-cell contact.


C) As naked DNA in solution.


D) By crossing over.


E) By a bacteriophage.






7)  Genetic change in bacteria can be brought about by


A) Conjugation.


B) Mutation.


C) Transduction.


D) Transformation.


E) All of the above.






8)  The initial effect of ionizing radiation on a cell is that it causes


A) Base substitutions.


B) The cells to get hot.


C) Bonding between adjacent thymines.


D) DNA to break.


E) The formation of highly reactive ions.






9)  According to the operon model, for the synthesis of an inducible enzyme to occur, the


A) Repressor must bind to the operator.


B) Repressor must not be synthesized.


C) End-product must not be in excess.


D) Substrate must bind to the repressor.


E) Substrate must bind to the enzyme.






10)  Synthesis of a repressible enzyme is stopped by


A) The corepressor binding to the operator.


B) The corepressor-repressor binding to the operator.


C) The end-product binding to the promoter.


D) The substrate binding to the repressor.


E) The allosteric transition.






Figure 8.2



11)  In Figure 8.2, if base 4 is thymine, what is base 4'?


A) Adenine B)  Uracil C)  Guanine D)  Thymine E)  Cytosine






12)  In Figure 8.2, if base 4 is thymine, what is base 11'?


A) Adenine B)  Thymine C)  Guanine D)  Uracil E)  Cytosine






13)  In Figure 8.2, base 2 is attached to


A) Phosphate.


B) Deoxyribose.


C) Thymine.


D) Ribose.


E) Can't tell.






14)  The damage caused by ultraviolet radiation is


A) Never repaired.


B) Repaired by DNA replication.


C) Cut out and replaced.


D) Repaired during transcription.


E) Repaired during translation.






Table 8.2


         Codon on mRNA and corresponding amino acid

         UUA  leucine UAA  nonsense

         GCA   alanine AAU  sparagine

         AAG  lysine  UGC   cysteine

         GUU  valine  UCG, UCU    serine



15)  (Use Table 8.2.) If the sequence of amino acids coded for by a strand of DNA is serine-alanine-lysine-leucine, what is the order of bases in the sense strand of DNA?
















16)  (Use Table 8.2.) If the sequence of amino acides coded for by a strand of DNA is  serine-alanine-lysine-leucine, the coding for the antisense strand of DNA is
















17)  The following steps are used to make DNA fingerprints. What is the third step?


A) Perform electrophoresis.


B) Collect DNA.


C) Add stain.


D) Digest with a restriction enzyme.


E) Lyse cells.






Figure 9.1




18)  How many pieces will EcoRI produce from the plasmid shown in Figure 9.1?


A) 4 B)  1 C)  5 D)  2 E)  3






19)  Which of the following can be used to make recombinant DNA?


A) Microinjection


B) Tungsten "bullets"


C) Protoplast fusion


D) Transformation


E) All of the above.






20)  The reaction catalyzed by reverse transcriptase.


A) mRNA rightarrow cDNA


B) DNA rightarrow DNA


C) DNA rightarrow mRNA


D) mRNA rightarrow protein


E) None






21)  Which of the following characterizes the Domain Bacteria?


A) Prokaryotic cells; ether linkages in phospholipids


B) Eukaryotic cells; ester linkages in phospholipids


C) Complex cellular structures


D) Multicellular


E) Prokaryotic cells; ester linkages in phospholipids






22)  If two organisms have similar rRNA sequences, you can conclude all of the following except


A) They will have similar G-C ratios.


B) They evolved from a common ancestor.


C) They will both ferment lactose.


D) They are related.


E) None of the above.






23)  The outstanding characteristic of the Kingdom Fungi is


A) Absorption of dissolved organic matter.


B) All members are photosynthetic.


C) Absorption of dissolved inorganic matter.


D) All members are microscopic.


E) All members are macroscopic.






24)  All of the following are true about the members of the Kingdom Animalia except


A) They have eucaryotic cells.


B) They are multicellular.


C) They use organic energy sources.


D) They use organic carbon sources.


E) They can photosynthesize.






25)  Which of the following are found primarily in the intestines of humans?


A) Gram-negative aerobic rods and cocci


B) Facultatively anaerobic gram-negative rods


C) Aerobic, helical bacteria


D) Gram-positive cocci


E) None of the above






26)  Staphylococcus and Streptococcus can be easily differentiated in a laboratory by which one of the following?


A) Cell shape


B) Ability to cause disease


C) Gram stain reaction


D) Growth in high salt concentrations


E) None of the above






27)  Which of the following genera is an anaerobic gram-negative rod?


A) Bacteroides


B) Treponema


C) Escherichia


D) Staphylococcus


E) None of the above






28)  Which of the following do you expect to be most resistant to high temperatures?


A) Streptococcocus pyogenes


B) Bacillus subtilis


C) Neisseria gonorrhoeae


D) Staphylococcus aureus


E) Eschericia coli






29)  Which of the following is not an enteric?


A) Shigella


B) Salmonella


C) Escherichia


D) Enterobacter


E) Campylobacter






30)  Which of the following is not a characteristic of spirochetes?


A) Difficult to culture in vitro


B) Gram-negative


C) Helical shape


D) Easily observed with brightfield microscopy


E) Possess an axial filament






31)  You have isolated a bacterium that grows in a medium containing an organic substrate and nitrate in the absence of oxygen. The nitrate is reduced to nitrogen gas. This bacterium is


A) A photoheterotroph.


B) Gram-negative.


C) A photoauttoph.


D) A chemoautotroph.


E) Using anaerobic respiration.






32)  Which of the following lacks a cell wall?


A) Mycobacterium


B) Mycoplasma


C) Borrelia


D) Nocardia


E) Clostridium






33)  All of the following statements about fungi are true except


A) All fungi have eukaryotic cells.


B) Few fungi are pathogenic to humans.


C) Most fungi are aerobic.


D) All fungi are unicellular.


E) Fungi are heterotrophic.






34)  All of the following statements about helminths are true except


A) They are heterotrophic.


B) They are multicellular animals.


C) Some have male and female reproductive organs in one animal.


D) All are parasites.


E) They have eukaryotic cells.






35)  All of the following are true about protozoa except


A) They have eukaryotic cells.


B) They may reproduce sexually.


C) All make cysts.


D) They may have flagella or cilia.


E) None of the above.






36)  Which of the following statements is false?


A) Fungal spores are used in identification of fungi.


B) Fungi produce sexual spores.


C) Fungal spores are resting spores to protect the fungus from adverse environmental conditions.


D) Fungal spores are for reproduction.


E) Fungi produce asexual spores.






37)  Transmission of helminthic diseases to humans is usually by 


A) Vectors.


B) Genitourinary route.


C) Gastrointestinal route.


D) Respiratory route.


E) All of the above.






38)  Which of the following is not a characteristic of parasitic platyhelminths?


A) They can be divided into flukes and tapeworms.


B) They are hermaphroditic.


C) They are dorsoventrally flattened.


D) They have a complete digestive system.


E) None of the above.






39)  All of the following arthropods transmit diseases while sucking blood from a human host except


A) Kissing bugs.


B) Fleas.


C) Lice.


D) Mosquitoes.


E) Houseflies.






40)  A definitive host harbors which stage of a parasite?


A) Cyst


B) Adult


C) Larva


D) Miracidium


E) All of the above






41)  In which of the following ways do viruses differ from bacteria?


A) Viruses don't have any nucleic acid.


B) Viruses are filterable.


C) Viruses are not composed of cells.


D) Viruses are obligate intracellular parasites.


E) All of the above.






42)  Which of the following provides the most significant support for the idea that viruses are nonliving chemicals?


A) They are not composed of cells.


B) They are chemically simple.


C) They cannot reproduce themselves outside of a host.


D) They cause diseases similar to those caused by chemicals.


E) They are filterable.






43)  Which of the following is not a method of culturing viruses?


A) In embryonated eggs


B) In cell culture


C) In culture media


D) In laboratory animals


E) None of the above






44)  Bacteriophages and animal viruses do not differ significantly in which one of the following steps?


A) Biosynthesis


B) Penetration


C) Adsorption


D) Release


E) Uncoating






45)  The definition of lysogeny is


A) Lysis of the host cell due to a phage.


B) When the burst time takes an unusually long time.


C) The period during replication when virions are not present.


D) Phage DNA is incorporated into host cell DNA.


E) None of the above.






46)  A viroid is


A) A complete, infectious virus particle.


B) A capsid without a nucleic acid.


C) A naked, infectious piece of RNA.


D) A provirus.


E) None of the above.






Figure 13.1



47)  In Figure 13.1, which of these is a complex virus?


A) A


B) B


C) C


D) D


E) All of the above






48)  A clear area against a confluent "lawn" of bacteria is called a


A) Cell lysis.


B) Pock.


C) Plaque.


D) Phage.


E) None of the above.






49)  Continuous cell lines differ from primary cell lines in that


A) Continuous cell lines can be maintained through an indefinite number of generations.


B) Viruses can be grown in continuous cell lines.


C) Continuous cell lines are derived from primary cell lines.


D) Continuous cell lines are from human embryos.


E) Continuous cell lines always have to be reisolated from animal tissues.






50)  A slow viral infection is an infection in which


A) Host cells are gradually lysed.


B) The disease process occurs gradually over a long period.


C) Viral replication is unusually slow.


D) The virus remains in equilibrium with the host without causing a disease.


E) Host cells are transformed.








1)  Answer:  D






2)  Answer:  C






3)  Answer:  C






4)  Answer:  A






5)  Answer:  D






6)  Answer:  C






7)  Answer:  E






8)  Answer:  E






9)  Answer:  D






10)  Answer:  B






11)  Answer:  A






12)  Answer:  B






13)  Answer:  B






14)  Answer:  C






15)  Answer:  A






16)  Answer:  D






17)  Answer:  D






18)  Answer:  D






19)  Answer:  E






20)  Answer:  A






21)  Answer:  E






22)  Answer:  C






23)  Answer:  A






24)  Answer:  E






25)  Answer:  B






26)  Answer:  D






27)  Answer:  A






28)  Answer:  B






29)  Answer:  E






30)  Answer:  D






31)  Answer:  E






32)  Answer:  B






33)  Answer:  D






34)  Answer:  D






35)  Answer:  C






36)  Answer:  C






37)  Answer:  C






38)  Answer:  D






39)  Answer:  E






40)  Answer:  B






41)  Answer:  C






42)  Answer:  C






43)  Answer:  C






44)  Answer:  A






45)  Answer:  D






46)  Answer:  C






47)  Answer:  B






48)  Answer:  C






49)  Answer:  A






50)  Answer:  B