What is an Hfr strain of bacteria?
What will be an ideal response?
Ans: An Hfr strain is one in which the F plasmid has become incorporated into the bacterial chromosome. It is called Hfr (for "high frequency of recombination") because during conjugation the donor Hfr cell will transfer bacterial genes to the recipient cell, giving the opportunity for new alleles to be introduced into the recipient genome by recombination.
You might also like to view...
Banner-tailed kangaroo rats, Dipodomys spectabilis, are rodents endemic to (found only in) the deserts of the southwestern United States. Which of the following is the best description of their niche?
A. seed-eating rodents that compete with other seed-eating organisms for food B. found in parts of Arizona, New Mexico, Texas, and Mexico C. found primarily in Sonoran and Chihuahuan deserts D. found only in arid habitats E. found primarily in areas with relatively heavy soils
Traditionally the animal(s) associated with hosting Brucella is/are
A. cattle. B. dogs. C. goats. D. pigs. E. All of the choices are correct.
Integration of body functions is controlled by
the a. respiratory system. b. nervous system. c. endocrine system. d. defense system. e. nervous system and the endocrine system.
Which of the following is NOT a major feature of
arthropods? a. jointed appendages b. exoskeleton c. paired segmental nephridia d. specialized and fused-together segments e. specialized sensory structures