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6th Grade Science / Lesson 5 - Moving In and Out of a Cell

Moving In and Out of Cells
What will we be learning today?


  • In this lesson, we are going to learn all about how things move in and out of cells .


How Can Things Move In and Out of a Cell?


  • Substances are flowing in and out of cells through the cell membrane all the time. Cells use substances to grow and get energy.

  • How does it work? The clue is that cells are in a moist environment. The process works something like ink and water.


What would happen if you placed a drop of food coloring in a bowl of water? You would probably observe the water slowly turn color.

Molecules of substances are in constant motion, even though you may not see the motion. As they move about, they often collide and bounce off one another.


This movement causes the food-coloring molecules to spread farther apart until they are evenly spaced throughout the water.

This process, called diffusion, occurs when molecules of a substance move from an area of higher concentration to an area of lower concentration.

That is, the molecules move from where they are crowded to where they are less crowded


lso occurs in gases. If you open a bottle of perfume or bake cookies, the aroma will gradually spread throughout your home.

Once the molecules that make up the aroma are in about the same concentration everywhere, they continue to collide and bounce off one another


What is happening in these pictures as you look from left to right?


Let's Review What We Learned Today!


  • Now complete your worksheet by using this Presentation