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6th Grade Science / Lesson 7 - Water Passes Through Cell Membranes

Water Passes Through Cell Membrane
What will we be learning today?


  • In this lesson, we are going to learn all about how water passes through cell membrane.


How Does Water Pass Through the Cell Membrane?


  • Do you realize that water makes up about 70 to 95 percent of a living cell, depending on the kind of cell it is? The movement of water in and out of a cell is important in keeping the cell alive.

  • The diffusion of water through a cell membrane is osmosis. Water molecules tend to move from an area of greater concentration to an area of lesser concentration.

  • When the concentration of water molecules is the same on each side of a cell membrane, a state of equilibrium, or balance, is reached.



  • You can see examples of osmosis around you. Look at the two photographs. The plant in the second photo is the same as the one in the first photo after it has been watered. How can you explain the wilting of the leaves in the first photograph?



  • Most likely there is less water in the soil around the roots. Cells in the leaves and stems of the plant are not supplied with adequate water from the roots.

  • The loss of water from the cell membranes causes them to shrink away from the cell. As a result the plant wilts. What other examples of osmosis can you think of?


Let's Review What We Learned Today!


  • Now complete your worksheet!