Bacteria use restriction enzymes to
a. integrate viral DNA.
b. destroy viral DNA.
c. prevent mutation of their DNA.
d. copy their genes.
e. inhibit the expression of some of their genes.
Answer: b
You might also like to view...
Beta-hemolytic group A streptococci are responsible for ________.
A. pharyngitis B. necrotizing fasciitis C. rheumatic fever D. All of the choices are correct.
Selection pressures acting on a population may favor
a. individuals at the left end of the range of variation. b. individuals at the right end of the range. c. extreme individuals at both ends of the range. d. the intermediate individuals within the range. e. all of these.
Simple diffusion of molecules occurs ________.
a. from an area of lesser concentration to an area of greater concentration b. in non-living systems as well as living systems c. across plasma membranes only through transport proteins
Which of the following statements correctly describes a portion of the pine life cycle?
A) Female gametophytes use mitosis to produce eggs. B) Seeds are produced in pollen-producing cones. C) Pollen grains contain female gametophytes. D) A pollen tube slowly digests its way through the triploid endosperm.