Which of these must occur during s phase of the cell cycle so that two daughter cells can be produced during m phase?
a the dna must be replicated. b the chromosomes must be joined. c the cytoplasm must be separated. d the cell membrane must be expanded

answer; ///i believe that the correct answer is (a) specialized cells)

a

explanation:

you must remain stopped until the stop signal is retracted and the red lights are turned off. approaching traffic in the opposite roadway of a divided highway shall not be required to stop, even if the school bus has the stop-arm extended and the alternately flashing warning signal lamps on.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.