Physical limits on the flow of into and of the cell prevent most cells from being too large.

materials/out

Explanation:

Physical limits on the flow of materials into and out of the cell prevent most cells from being too large.

The limitation of the kind and amount of materials that flow into and out of the cell prevents the cell from being too large. The function of selectively allowing materials to enter and leave the cell is carried out by the cell membrane. While being permissible to some materials, it shuts some materials off and, thus, the size of the cell is maintained.

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is correct hope this   also i learnd this in middle school

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.