A Free Lesson on Cell Walls

I have been participating in Teaching Blog Addict's Science Week this week. Today's Linky is for Science Freebies and Science Unit Sales. I didn't have anything to contribute, until Dawson was working on a plant cell microscope lab this morning.

One of the questions posed was: Why doesn't an animal cell have a cell wall, when a plant cell does?

Here is the technical answer from Wikipedia:

The cell wall structure provides a lot of support and stabilizes the overall structure of the plant. Cells can't move around. In animals, multiple interactions between cells and molecules around them (referred to as the extracellular matrix) help to hold everything in place but animals have no real equivalent to the, relatively rigid, cell wall.

Dawson had an example to share:

He put water in a glass to represent the plant cell with cell wall. It was stable, and the cell did not move. And he dropped three drops of water on the kitchen counter, to represent animal cells with no cell wall (glass enclosure).

After time they began to start to move toward each other.

Eventually they attached to one another. They never fell apart and disintegrated. They were stabilized by each other.

This was a great visual for what he was studying. And it is your Science Freebie.