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Answer 4 out of 5 questions correctly.

To function properly, a cell must maintain an optimal water balance. Cell membranes are permeable to water, so a cell's water balance is affected by its surroundings. Water molecules pass through the cell membrane via a process known as

osmosis.

This video shows water molecules crossing the cell membrane via osmosis.

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Complete the paragraph.

At the start of the video, there is a concentration of water molecules inside the cell than outside the cell. The water molecules cross the cell membrane in . water molecules move from inside the cell to the outside, until the concentration outside the cell is the concentration inside the cell.