so here are some of the questions I came by from the set of practice questions for my exam that I'm not really sure of the answer for it...
1. Temperate phages have genes for
a. enzymes c. repressors
b. capsomeres d. all the above
2. Transformation in bacteria
a. is the transfer of DNA from one bacterium to another by use of a phage
b. is able to convert mutants into wild-type organisms
c. is a primitive sexual mechanism dependent on the fertility factor
d. is limited to genes adjacent to prophage attachment sites
3. Plasmids which can be transferred by conjugation
a. contain transfer genes c. contain restriction sites
b. code for restriction enzyme(s) d. all the above
4. Homologous recombination between two double stranded DNA molecules requires which order of events (from
left to right).
a. pairing of two chromosomes to form a four stranded structure, action of recombination enzymes to
separate the four strands into two double stranded molecules.
b. generation of circular molecule, nicking of one strand for transfer to the recipient
c. formation of a single stranded fragment with a 3’ end, invasion of double stranded molecule by the 3’ end
of the fragment.
d. DNA ligase action to generate a partially single stranded fragment of DNA, invasion of double stranded
molecule by the single stranded fragment
5. Site - specific recombination is similar to homologous recombination because
a. enzymes are required in both
b. recombination proteins recognize a certain sequence of nucleotides in both DNA molecules
c. single strands of DNA participate in both
d. both are required in binary fission
6. Formation of generalized transducing particles
a. requires transformation c. is limited by restriction
b. takes place during phage growth d. is inhibited by repressor
7. Generalized transducing particles
a. package chromosomal fragments after infecting the donor
b. are formed during lytic growth of a phage in a bacterial host
c. carry donor genes to recipient cells
d. all the above
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