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1

Which is true about biological reduction of nitrogen gas to ammonia?
A. Can be accomplished by free-living organisms in Domains Archaea and Bacteria.
B. Can be accomplished by a variety of symbioses between prokaryotes and eukaryotic macroorganisms
C. Is thermodynamically exergonic but requires high input of cellular energy (ATP)
D. Is catalyzed by an enzyme that typically contains iron and molybdenum co-factors.
E. All of the above

E. All of the above

2

Which of the below principles apply to the tendency of systems to go toward a higher state of disorder, and argue that perpetual motion is not attainable?
A. entropy
B. First Law of Thermodynamics
C. Second Law of Thermodynamics
D. A and C
E. Chemiosmotic Theory

D. A and C

3

Enzymes by which bacteria assimilate gaseous molecular nitrogen is/are
A. glutamine synthetase (GS)
B. glutamate synthase (GOGAT)
C. glutamate dehydrogenase (GDH)
D. nitrogenase
E. Both C and D

D. nitrogenase

4

The Ames test...
A. determines histidine resistance of Salmonella typhimurium
B. uses of Salmonella typhi
C. depends on reversion of histidine auxotrophs to prototrophy
D. assesses chemical mutagenicity
E. Both C and D

E. Both C and D

5

Hfr strains of E. Coli...
A. are characterized by an F-factor that has has integrated into the chromosome
B. may form an F' plasmid that contains chromosomal genetic material
C. are "male" or donor cells
D. Have sex pili
E. All of the above

E. All of the above

6

Which mechanism may protect nitrogenase from denaturation by molecular oxygen?
A. Fixation of nitrogen only under anaerobic conditions
B. Compartmentalization of the nitrogen fixation process
C. Partial uncoupling of the respiratory chain (ETC) to effect rapid reduction of oxygen
D. Oxygen transport proteins such as hemoglobins to sequester oxygen from nitrogenase
E. All of the above

E. All of the above

7

A bacterium experiencing a severe amino acid shortage
A. may exhibit Stringent Response
B. will contain elevated levels of ppGpp
C. will continue biosynthesis of amino acids
D. will have high level of uncharged tRNA
E. will have all of the above properties

E. All of the above

8

Conditional mutants...
A. have biosynthetic deficiencies relative to the prototroph
B. only express their mutant phenotype under certain defined conditions
C. are deficient in DNA repair mechanisms
D. are useful in determining potential carcinogenicity of chemicals
E. are all except C

B. only express their mutant phenotype under certain defined conditions

9

The capability of a bacterial strain or species to take up naked DNA is called
A. fertility
B. promiscuity
C. transduction
D. competence
E. lysogeny

D. competence

10

The process by which DNA is transferred from one bacterium to another by a virus

Transduction

11

A bacterial cell in which a phage exists as DNA in its dormant state. A prophage is either integrated into the host bacteria's chromosome or more rarely exists as a stable plasmid within the host cell.

Lysogenic bacterium

12

"Anal was I ere I saw lana," "A man, a plan, a canal, panama," "He goddam mad dog eh," and "Naomi, sex at noon taxes, I moan"
A. palindromes of alphabetic letters
B. analogous to insertion sequence sites
C. analogous to recognition sites for restriction endonucleases
D. All of the above
E. wisdom so profound that if you graduate without knowing them, UWF should lose accreditation

D. All of the above

13

Which of the below contributed most to our understanding of sex in bacteria?
A. Paul Berg
B. Joshua Lederberg and Edward Tatum
C. Myron Sasser
D. Max Delbruick and Salvador Luria

B. Joshua Lederberg and Edward Tatum

14

The DNA site on operons to which a regulator (repressor) protein may bind is known as which of the below?
A. allosteric site
B. operator
C. promoter
D. leader
E. attenuator

B. operator

15

The computer scientist at University of Indiana writes for Scientific American. He/she wrote about Central Dogma in treatise covering "Godel, Escher, Bach: An Eternal Golden Braid"
A. Michael Moore
B. Rita Colwell
C. Douglas Hofstadter
D. Michael Crichton
E. Myron Sasser

C. Douglas Hofstadter

16

The key enzyme by which bacteria assimilate relatively-LOW concentrations of ammonia is
A. glutamine synthetase
B. glutamate synthase (GOGAT)
C. glutamate dehydrogenase
D. nitrogenase
E. A and B

E. A and B

17

Plasmid copy number is which of the below?
A. The same as chromosomal copy number
B. The total copies of a plasmid in a single cell
C. How efficiently a plasmid is copied during cell division
D. The ratio between the numbers of a specific plasmid inside a bacterial cell and the number of chromosomes
E. The number of genes carried on each plasmid

D. The ratio between the numbers of a specific plasmid inside a bacterial cell and the number of chromosomes

18

Nonsense mutations...
A. occur when translation "stop codons" are prematurely inserted into mRNA
B. stop translation of the mRNA into a functional protein
C. have been given trivial names of "Amber," "Opal" and "Ochre"
D. often result in a defective gene product
E. All of the above

E. All of the above

19

Nonsense-suppressor mutations...
A. allow a translation stop codon to be ignored
B. require a change in tRNA specificity
C. restore in the original, wild phenotype
D. result in substitution of an amino acid into the position specified by the stop codon in the mRNA
E. All of the above

E. All of the above

20

A key enzyme of the Calvin-Benson-Bassham cycle is
A. hexokinase
B. RuBisCO
C. pyruvate dehydrogenase
D. nitrogenase
E. lysozyme

B. RuBisCO

21

The enzyme nitrogenase...
A. consists of two kinds of subunits
B. may catalyze reduction of substrates other than nitrogen gas
C. is highly conserved in Domains Bacteria and Archaea
D. is rare, but present in Domain Eukarya
E. is characterized by statement in items A, B, and C but not D

E. is characterized by statement in items A, B, and C but not D.

22

The use of nitrate as a terminal electron acceptor by some organisms is...
A. anaerobic nitrate respiration
B. common in heterotrophic macro-organisms including humans
C. dissimilatoy nitrate reduction, known as denitrification
D. all of the above
E. all except B

E. all except B

23

Which bacteriophage is the model for specialized transduction?
A. coliphage 42
B. coliphage Lambda
C. T-even coliphage
D. General transduction phages
E. None of the above

B. coliphage Lambda

24

The rolling circle mechanism of DNA replication is utilized...
A. during conjugative transfer of DNA into an F-recipient
B. during replication of DNA of some viruses
C. during most replication of bacterial chromosomes
D. Both A and B
E. by Eukarya

D. Both A and B

25

What principle metabolic advantage does fermentation confer to the cell?
A. Oxidizes reduced electron carriers such as NADH
B. Produces useful metabolic byproducts such as ethanol, acetone, lactic acid
C. generates a prodigious quantity of ATP
D. All of the above
E. A and B only

A. Oxidizes reduced electron carriers such as NADH

26

Which of the below mapping methods will give information on the polar relationship of two genes, e.g., whether gene B is between A and C?
A. co-transformation
B. co-transduction
C. interrupted conjugation
D. sequencing of DNA bases
E. all of the above

C. Interrupted conjugation

27

Uncoupled transport of electrons via an electron transport system to a terminal electron acceptor tends to generate
A. proton motive force
B. ATP
C. NADH
D. heat
E. none of these

D. heat

28

What is the standard unit for mapping the genes on the E. Coli chromosome?
A. gene length
B. base pair
C. minute
D. second
E. degree

C. minute

29

Which possible fates for DNA that has been introduced (exogenote) into a new host cell result in the MOST stable transfer into future generations of the recipient cell?
A. digestion catalyzed by hos enzymes
B. formation of a partial diploid cell
C. recombination with the endogenote
D. Formation of a partial diploid clone
E. All of the above

C. recombination with the endogenote

30

Okasaki fragments...
A. are proteins
B. encode housekeeping function of the cell
C. allow the lagging strand of new DNA synthesis to occur
D. accommodate the fact that DNA polymerase must synthesize the new strand from 5' to 3'.
E. C and D

E. C and D