Rarely, the conjugation of Hfr and F− cells produces two Hfr cells. Explain how this event takes place.

"F" on account of E.coli show the fertility factor. Cells possessing this factor (called donors) hold the ability to move the hereditary material over the strains by a procedure called conjugation. F-factor exists as a free element (cell is called episome) or integrated into bacterial chromosome (cell is called Hfr-High frequency recombinant). Cells with no F factor are recipients.

In a Conjugation between a F+ and F-cell just F factor from F+ cell gets moved o produce two F+ cells. But during a Hfr and F-conjugation as the F factor is incorporated into the chromosome and by the intrinsic idea of F factor to get moved the Hfr cells attempt to move their whole genetic material across and there are two outcomes wherein one case there is a fragmented exchange of hereditary material and the recipient cell remain F-and when there is a finished exchange of hereditary material the cell becomes Hfr yet this is uncommon as the time taken for the total exchange of hereditary material is excessively long for the cells to remain contact.

what statement best describes the difference between the sympathetic and parasympathetic nervous systems?

the sympathetic nervous system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. the parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.

correct answer: understand the different control methods available

integrated pest management is an strategy that is based on the ecosystem and try to prevent the pest and the damage caused by them by applying combination of technique like habitat manipulation, biological control and use of resistant varieties.

the main aim of the integrated pest management is not to completely eliminate the pest but to strengthen the ecosystem so that conditions are favorable for plants and unfavorable for pests.